Dynamic opening and closing characteristic simulation method for bidirectional fluid-solid coupling flexible umbrella structure

Abstract

The invention relates to a dynamic opening and closing characteristic simulation method for a bidirectional fluid-solid coupling flexible umbrella structure, which is applied to dynamic simulation of a working umbrella in an umbrella ladder type high-altitude wind power generation system, and comprises the following steps: establishing a working umbrella model and a flow field model around the working umbrella; wherein the acting umbrella model is constructed based on a concentrated mass method; the flow field model is constructed based on a smoothed particle fluid dynamics method; constructing a bidirectional fluid-solid coupling system based on the acting umbrella model and the flow field model; wherein interaction exists between a part of composition units corresponding to the acting umbrella model and a part of composition units corresponding to the flow field model in the bidirectional fluid-solid coupling system; and carrying out analogue simulation based on the bidirectional fluid-solid coupling system, and solving the dynamic information of the acting umbrella model and the dynamic information of the flow field model corresponding to each time step so as to determine the characteristics of the acting umbrella in the dynamic opening and closing process. According to the invention, the dynamic behavior of the acting umbrella in the strong dynamic complex flow field is efficiently simulated.

Description

Technical Field

[0001] The present invention relates to the field of high-altitude wind energy technology, and in particular to a method for simulating dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling. Background Art

[0002] The parachute-ladder high-altitude power generation system is one of the technical implementation paths in the field of high-altitude wind power generation. As the core force-bearing structure of the parachute-ladder high-altitude power generation system, the dynamic behavior of the work parachute in a strong dynamic and complex wind field will directly affect whether the parachute-ladder high-altitude power generation system has the ability to generate electricity stably in a high-altitude environment.

[0003] Currently, there is a lack of simulation solutions for the dynamic characteristics of the working parachute in the parachute ladder type high altitude wind energy development system. Summary of the invention

[0004] In view of this, the present disclosure proposes a method, device, electronic device and storage medium for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling.

[0005] According to one aspect of the present disclosure, a method for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling is provided, which is applied to the dynamic simulation of a working umbrella in an umbrella-ladder high-altitude wind power generation system, and the method comprises:

[0006] Establishing a work-doing parachute model and a flow field model around the work-doing parachute; wherein the work-doing parachute model is constructed based on a lumped mass method; and the flow field model is constructed based on a smoothed particle fluid dynamics method;

[0007] Based on the work-doing umbrella model and the flow field model, a bidirectional fluid-solid coupling system is constructed; wherein, in the bidirectional fluid-solid coupling system, there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model;

[0008] Based on the bidirectional fluid-solid coupling system, simulation is performed to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-doing umbrella in the dynamic opening and closing process.

[0009] In a possible implementation, the component unit of the work-doing umbrella model includes a plurality of mass points;

[0010] The step of establishing the work-doing parachute model comprises:

[0011] The work-doing parachute is described by using the concentrated mass method to obtain the multiple mass points;

[0012] For any mass point among the plurality of mass points, determine a mechanical unit corresponding to the mass point, wherein the mechanical unit is used to connect the mass point with at least one other mass point among the plurality of mass points; the mechanical unit includes: one or more of a bending spring, a shear spring and a tension spring;

[0013] The work-doing umbrella model is established based on the multiple mass points and the mechanical units corresponding to each of the multiple mass points.

[0014] In a possible implementation, the component unit of the flow field model includes a plurality of fluid particles;

[0015] The step of establishing a flow field model around the working parachute comprises:

[0016] Based on the work-doing umbrella model, determining a target flow field so that the work-doing umbrella model is immersed in the target flow field;

[0017] Using the smoothed particle fluid dynamics method, determining a plurality of fluid particles within the target flow field;

[0018] The flow field model is established based on the multiple fluid particles.

[0019] In a possible implementation, the simulation based on the bidirectional fluid-solid coupling system is performed to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, including:

[0020] At any time step, performing a penetration test between each fluid particle in the flow field model and each surface element in the work-doing umbrella model, and between different surface elements in the work-doing umbrella model, wherein any surface element is composed of a plurality of particle points in the work-doing umbrella model;

[0021] Based on the mold penetration detection result, determining the fluid particles and particles that interact with each other in the bidirectional fluid-solid coupling system, and the different particles that interact with each other;

[0022] Calculating the force between the interacting fluid particles and the mass points, and the force between the interacting different mass points, by using a penalty function;

[0023] Determining the dynamic information of the flow field model corresponding to the time step based on the interaction forces between the interacting fluid particles and the mass points and the interaction forces between the fluid particles in the flow field model;

[0024] Based on the forces between the interacting fluid particles and the mass points, the forces between the interacting different mass points, and the forces of the mechanical units corresponding to the mass points in the work-doing umbrella model, the dynamic information of the work-doing umbrella model corresponding to the time step is determined.

[0025] In a possible implementation, determining the dynamic information of the flow field model corresponding to the time step based on the force between the interacting fluid particles and the mass points and the force between the fluid particles in the flow field model includes:

[0026] For each fluid particle in the flow field model, a neighborhood search is performed, and a density attribute of the fluid particle is updated according to the neighborhood search result;

[0027] According to the density attribute of the fluid particle, the pressure attribute of the fluid particle is updated;

[0028] Determine the force between the fluid particle and other fluid particles based on the current velocity of the fluid particle, the density attribute, the pressure attribute, and the viscosity attribute;

[0029] Based on the interaction force between the fluid particle and other fluid particles and the interaction force between the fluid particle and the mass point in the work-doing umbrella model, the dynamic information of the fluid particle corresponding to the time step is determined.

[0030] In a possible implementation, determining the dynamic information of the work-doing umbrella model corresponding to the time step based on the force between the interacting fluid particles and the mass points, the force between the interacting different mass points, and the force of the mechanical unit corresponding to each mass point in the work-doing umbrella model includes:

[0031] For each mass point in the work-doing umbrella model, based on the force of the tension spring borne by the mass point, the force of the shear spring borne by the mass point, and the force of the bending spring borne by the mass point, the force of the mechanical unit corresponding to the mass point is determined;

[0032] Determine the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particle in the work-doing umbrella model;

[0033] Based on the force of the mechanical unit corresponding to the particle, the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particle in the work-doing umbrella model, the dynamic information of the particle corresponding to the time step is determined.

[0034] In a possible implementation, the step size corresponding to each time step is determined by the density of fluid particles in the target flow field.

[0035] According to another aspect of the present disclosure, a dynamic opening and closing characteristic simulation device of a flexible umbrella structure with bidirectional fluid-solid coupling is provided, which is applied to the dynamic simulation of a working umbrella in an umbrella ladder type high-altitude wind power generation system, and the device comprises:

[0036] A modeling module, used to establish a work-doing parachute model and a flow field model around the work-doing parachute; wherein the work-doing parachute model is constructed based on a lumped mass method; and the flow field model is constructed based on a smoothed particle fluid dynamics method;

[0037] The modeling module is further used to construct a bidirectional fluid-solid coupling system based on the work-doing umbrella model and the flow field model; wherein, in the bidirectional fluid-solid coupling system, there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model;

[0038] A simulation module is used to perform simulation based on the bidirectional fluid-solid coupling system to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-doing umbrella during the dynamic opening and closing process.

[0039] According to another aspect of the present disclosure, an electronic device is provided, comprising: a processor; and a memory for storing processor-executable instructions; wherein the processor is configured to implement the above method when executing the instructions stored in the memory.

[0040] According to another aspect of the present disclosure, a non-volatile computer-readable storage medium is provided, on which computer program instructions are stored, wherein the computer program instructions implement the above method when executed by a processor.

[0041] According to another aspect of the present disclosure, a computer program product is provided, including a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code. When the computer-readable code runs in a processor of an electronic device, the processor in the electronic device executes the above method.

[0042] Through various aspects of the present disclosure, a work-making parachute model and a flow field model around the work-making parachute are established; wherein the work-making parachute model is constructed based on the lumped mass method; the flow field model is constructed based on the smooth particle fluid dynamics method; based on the work-making parachute model and the flow field model, a two-way fluid-solid coupling system is constructed; wherein there is interaction between the partial component units corresponding to the work-making parachute model and the partial component units corresponding to the flow field model in the two-way fluid-solid coupling system; simulation is performed based on the two-way fluid-solid coupling system to solve the dynamic information of the work-making parachute model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-making parachute in the dynamic opening and closing process. Thus, the dynamic simulation of the work-making parachute in the parachute ladder type high-altitude wind power generation system is realized. In this way, a work parachute model is constructed based on the concentrated mass method, and a flow field model around the work parachute is constructed based on the smooth particle fluid dynamics method, so that the parachute body and the surrounding fluid of the work parachute in the two-way fluid-solid coupling system are both modeled by Lagrangian particles; then, a multiple time stepping strategy is adopted to couple and solve the two-way fluid-solid coupling system, and the dynamic information of the work parachute model and the dynamic information of the flow field model corresponding to each time step are solved, so as to determine the characteristics of the work parachute in the dynamic opening and closing process; compared with traditional simulation methods, the method in the embodiment of the present disclosure can complete a high-precision simulation of the dynamic behavior of the work parachute in a strong dynamic complex wind field in a shorter time, and in addition, the flow field changes around the work parachute can also be obtained. It can be applied to the analysis and prediction of the working conditions of the work parachute in actual engineering, so as to better assist the design and operation optimization of land-based high-altitude wind power generation systems and promote the development of new energy development and other fields.

[0043] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the disclosure and, together with the description, serve to explain the principles of the disclosure.

[0045] Figure 1 A schematic structural diagram of a land-based high-altitude wind power generation system according to an embodiment of the present disclosure is shown.

[0046] Figure 2 A flow chart of a method for simulating dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling according to an embodiment of the present disclosure is shown.

[0047] Figure 3 A schematic structural diagram of a work-performing umbrella in a folded state according to an embodiment of the present disclosure is shown.

[0048] Figure 4A schematic structural diagram of a working umbrella in a fully opened state according to an embodiment of the present disclosure is shown.

[0049] Figure 5 A structural diagram of a bidirectional fluid-solid coupling system according to an embodiment of the present disclosure is shown.

[0050] Figure 6 A schematic diagram showing a simulation result of a dynamic change process of a parachute of a working parachute according to an embodiment of the present disclosure.

[0051] Figure 7 A flow chart of a method for performing simulation based on a bidirectional fluid-solid coupling system according to an embodiment of the present disclosure is shown.

[0052] Figure 8 A schematic diagram showing a working umbrella in a closed state and an open state according to an embodiment of the present disclosure is shown.

[0053] Fig. 9 A flow chart of a simulation according to an embodiment of the present disclosure is shown.

[0054] Fig.10 A structural diagram of a device for simulating dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling according to an embodiment of the present disclosure is shown.

[0055] Fig.11 A block diagram of an electronic device 1900 according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0056] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0057] References to "one embodiment" or "some embodiments" etc. described in this specification mean that one or more embodiments of the present disclosure include specific features, structures or characteristics described in conjunction with the embodiment. Thus, the phrases "exemplary", "in one embodiment", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0058] In the present disclosure, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: including the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or plural.

[0059] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present disclosure.

[0060] First, possible application scenarios of the work-doing umbrella simulation method in the embodiment of the present disclosure are exemplarily described below.

[0061] Figure 1 FIG. 2 shows a schematic diagram of the structure of a land-based high-altitude wind power generation system according to an embodiment of the present disclosure. Figure 1 As shown, the land-based high-altitude wind energy power generation system may include: an aerial device and a ground device;

[0062] Exemplarily, the aerial device may include a helium balloon, a work parachute, a cable, etc.; wherein the helium balloon is used to provide lift for the work parachute, so that the work parachute rises to a set height; the work parachute is used to capture wind energy at high altitudes and convert it into mechanical energy, thereby driving the generator on the ground to generate electricity; the cable is used to connect the work parachute, helium balloon and other aerial devices with the ground device. The aerial device of the land-based high-altitude wind power generation system has the advantages of light weight, low safety risk, large-scale and large-scale. As an example, a number of work parachutes can be set on the cable to form a parachute ladder type high-altitude wind power generation system.

[0063] Exemplarily, the ground device may include a universal wheel, a tensioning device, a winch, and a generator, etc.; wherein the universal wheel is used to adapt to changes in wind direction at high altitudes, ensuring that the direction of the cable can be adjusted with changes in wind direction, thereby maximizing the capture of wind energy; the tensioning device is used to maintain the tension of the cable, ensuring that the cable is stable and effectively converts the wind force at high altitudes into mechanical energy; the winch is connected to the working parachute through a cable; the generator is driven by the winch to generate electrical energy, and can transmit and distribute the electrical energy through the transmission network.

[0064] The power generation principle of the land-based high-altitude wind power generation system is as follows: the generator is placed on the ground, and at the same time, like "flying and retracting a kite", the parachute moves up and down in a circular motion to achieve power generation in the air and on the ground; specifically, a helium balloon can be used to provide the initial lift for the parachute, and the parachute is opened after rising to a certain height. The parachute is tied to a cable and drives the cable to reciprocate and pull the ground generator turntable to rotate under the action of wind, and the mechanical energy is converted into electrical energy to achieve power generation.

[0065] It should be noted that the structure of the above-mentioned land-based high-altitude wind power generation system is only an example, and may also include more or less equipment, without limitation.

[0066] Among them, the working parachute can also be called a flexible parachute. It is a flexible large deformation structure. During operation, it needs to be dynamically opened and closed repeatedly. The movement posture in the wind is complex. The simulation of its dynamic opening and closing process is a key link in the design and optimization of high-altitude wind power generation systems. Compared with traditional experimental methods, simulation has the advantages of high efficiency, short time consumption, resource saving, no restrictions on experimental sites and data, and easy explanation of mechanical mechanisms. At present, there is a lack of simulation schemes for the dynamic characteristics of working parachutes in parachute ladder-type high-altitude wind energy development systems. The closest to the simulation of working parachutes is the research on parachutes, but parachutes are generally opened once and fall vertically, which is completely different from the dynamic process of working parachutes in this disclosure. The typical simulation method for the most similar parachute is mainly the coupling of grid-based computational fluid dynamics method and solid motion. For example, the CFD (Computational Fluid Dynamics) method is used to couple the MSD (Mass Spring Damper) model to complete the simulation of the dynamic behavior characteristics of the canopy structure during the parachute opening process, taking into account the deformation characteristics and energy dissipation of the canopy structure. For another example, the improved modeling technology based on the FSI (Fluid-Structure Interaction) method is used to describe the falling and gliding performance of a conceptual parachute design with geometric complexity. The core of this modeling method is to construct a deformable airspace / stable space-time domain to simulate the movable boundary and fluid-solid interface to characterize more complex fluid-solid coupling phenomena. At the same time, this method provides a more precise grid movement method, reduces the number of grid re-divisions, reduces the difficulty of describing geometrically complex canopies, and improves the convergence level of iterative solution results. For another example, the SSTFSI (Stabilized Space-Time Fluid-Structure Interaction) method is used to simulate the dynamic behavior characteristics of the canopy structure during the parachute opening process. The SSTFSI technology is an improvement on the grid-based fluid-structure interaction modeling method FSI, which is suitable for the situation where the fluid and structural grids at the interface are incompatible. For another example, the simulation of the finite mass parachute opening process is completed based on the ALE (Arbitrary Lagrangian Euler) method and grid adaptation technology.

[0067] However, the above research methods for parachutes are all based on flow field grid generation. Such methods have great limitations when dealing with large deformation problems, and will generate huge computational consumption in the calculation of the motion state of the parachute system.

[0068] The disclosed embodiment provides a method for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling (see below for detailed description). The method is based on the coupling of the concentrated mass method and the smoothed particle hydrodynamics method (Smoothed Particle Hydrodynamics, SPH) to simulate an aerial working parachute in a land-based high-altitude wind power generation system. The method can efficiently simulate the dynamic behavior of the working parachute in a highly dynamic and complex flow field.

[0069] Among them, the concentrated mass method replaces the continuous structure with discrete particles, and represents the corresponding properties of the original structure by describing the properties of the particle group (i.e., a mechanical system composed of many particles that interact with each other), such as displacement and acceleration; this method can be applied to simplify the dynamic simulation of complex continuous structures. The smooth particle fluid dynamics method is a gridless fluid dynamic analysis method, which avoids problems such as grid distortion that may occur in the calculation process of traditional grid models, and is not affected by the randomness of actual particle distribution, and the free boundary of the generated model will not have numerical divergence. Therefore, compared with traditional methods, the concentrated mass method-SPH coupling mode in the disclosed embodiment is more suitable for simulating the situation where a flexible work-doing umbrella moves violently and undergoes significant deformation in a highly dynamic and complex flow field.

[0070] The work-doing parachute simulation method provided by the embodiment of the present disclosure is described in detail below.

[0071] Figure 2 A flowchart showing a method for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling according to an embodiment of the present disclosure is shown. The method is applied to the dynamic simulation of a working umbrella in an umbrella ladder type high altitude wind power generation system. For example, Figure 1 By way of example, the method may be performed by a processing device having data processing capabilities, such as a computer, a processor, a server, etc. Figure 2 As shown, the method may include the following steps:

[0072] Step 201, establishing a work-doing parachute model and a flow field model around the work-doing parachute; wherein the work-doing parachute model is constructed based on a lumped mass method; and the flow field model is constructed based on a smoothed particle fluid dynamics method.

[0073] Exemplarily, before establishing the model of the active parachute, the components, size, shape and other parameters of the active parachute can be pre-set as needed. For example, the components of the active parachute can include a parachute body, parachute ropes, etc., wherein the parachute body can include parachute body reinforcement ribs and parachute canopy, etc.; the size of the active parachute can include: the parachute head diameter of the parachute body, etc.; the shape of the active parachute can be square, circular, airfoil, double cone, strip, guide surface, and rotating, etc. It can be understood that during the operation of the active parachute, the state of the active parachute will continue to change, and accordingly, the shape of the active parachute will also change. At the same time, since the active parachute will dynamically open and close repeatedly during the operation process, the parameters of the active parachute when the active parachute is in a folded state can be simulated through a natural falling process based on the parameters of the active parachute in a fully opened state. Figure 3 A schematic structural diagram of a work-performing umbrella in a folded state according to an embodiment of the present disclosure is shown.

[0074] Furthermore, a work-doing umbrella model is constructed based on the concentrated mass method. Exemplarily, the component units of the work-doing umbrella model include multiple particle points; wherein the number, density, distribution, etc. of the particle points included in the work-doing umbrella model can be set according to needs, and there is no limitation on this; it can be understood that as the simulation proceeds, the state of the work-doing umbrella will continue to change, and the speed and position of each particle point in the work-doing umbrella model will also continue to change; exemplarily, the initial speed of each particle point in the work-doing umbrella model can be set to zero, and the initial position of each particle point in the work-doing umbrella model can be the coordinates of each particle point in a preset coordinate system when the work-doing umbrella is in a fully opened state.

[0075] In a possible implementation, the establishment of the work-doing umbrella model includes: using the lumped mass method to describe the work-doing umbrella to obtain the multiple mass points; for any mass point among the multiple mass points, determining the mechanical unit corresponding to the mass point, wherein the mechanical unit is used to connect the mass point with at least one other mass point among the multiple mass points; the mechanical unit includes: one or more of a bending spring, a shear spring, and a tension spring; based on the multiple mass points and the mechanical units corresponding to each of the multiple mass points, the work-doing umbrella model is established. Exemplarily, the lumped mass method can be used to describe the work-doing umbrella in a fully opened state, so that the work-doing umbrella is represented by multiple mass points, and the Lagrangian particle modeling of the work-doing umbrella body is realized; for each mass point, the mechanical unit corresponding to the mass point includes a bending spring, a shear spring, and a tension spring, and the mass point is connected to other different mass points through different springs, so that the mass-spring model is established, which is the work-doing umbrella model. Figure 4 FIG. 1 is a schematic structural diagram of a power-generating parachute in a fully opened state according to an embodiment of the present disclosure. Figure 4As shown, the finite mass method (i.e., concentrated mass method) is used to describe the parachute body of the work-doing parachute with mass points, and each mass point is a component unit of the work-doing parachute model, wherein the bending spring, the shear spring, and the tension spring are the mechanical units corresponding to each mass point; in this way, based on the concentrated mass method, the description of the parachute body reinforcement ribs and the canopy fabric of the work-doing parachute is realized by combining different mechanical units such as the bending spring, the shear spring, and the tension spring.

[0076] Furthermore, a flow field model around the working umbrella can be established based on the smooth particle fluid dynamics method. For example, the component units of the flow field model include multiple fluid particles (also referred to as particles, SPH particles, and fluid particle micro-elements); wherein the number, density, distribution, and other conditions of the fluid particles contained in the flow field model can be set according to needs, and there is no limitation on this; it can be understood that as the simulation proceeds, due to the interaction between the working umbrella and the air, the position and velocity of the fluid particles in the flow field model will continue to change. For example, the initial velocity of the fluid particles in the flow field model can be the wind speed to be simulated, and the initial position of the fluid particles can be the coordinates of each fluid particle in a preset coordinate system.

[0077] In a possible implementation, the establishment of the flow field model around the work-doing umbrella includes: determining the target flow field based on the work-doing umbrella model so that the work-doing umbrella model is immersed in the target flow field; using the smooth particle fluid dynamics method to determine a plurality of fluid particles in the target flow field; and establishing the flow field model based on the plurality of fluid particles. Among them, the shape, range, and boundary conditions of the target flow field can be set according to demand under the condition that the work-doing umbrella model can be immersed in the target flow field; further, all the fluid particles in the target flow field can be used as the fluid particles in the flow field model around the work-doing umbrella, and each fluid particle carries part of the mass of the fluid and has velocity properties, density properties, pressure properties, and viscosity properties, thereby realizing the establishment of the flow field model around the work-doing umbrella in the target flow field. Considering that as the simulation progresses, the relative positions of each fluid particle in the flow field model and each particle in the work-doing umbrella model are constantly changing, the work-doing umbrella model may overflow the target flow field. Therefore, during the simulation, the target flow field can be updated regularly. For example, some fluid particles that exceed the range can be deleted in the current flow field according to the latest positions of each particle in the work-doing umbrella model, and some new fluid particles can be added at the entrance position of the target flow field to maintain the macroscopic continuity of the fluid. The properties of the new fluid particles can be determined based on the properties or initial properties of the fluid particles in the previous time step, thereby ensuring that the work-doing umbrella model can always be immersed in the updated target flow field. Correspondingly, as the target flow field is updated, the fluid particles in the flow field model will also increase and decrease accordingly, thereby synchronously updating the flow field model. Figure 5 A structural diagram of a bidirectional fluid-solid coupling system according to an embodiment of the present disclosure is shown as follows: Figure 5 As shown, the target flow field is a rectangular space, the inlet plane and the outlet plane of the target flow field are perpendicular to the movement direction of the work-doing umbrella, and the four side surfaces of the target flow field are parallel to the movement direction of the work-doing umbrella; illustratively, the average distance between the inlet plane of the target flow field and the canopy of the work-doing umbrella is not less than the head diameter of the work-doing umbrella, the average distance between the outlet plane of the target flow field and the canopy of the work-doing umbrella is not less than five times the head diameter of the work-doing umbrella, and the average distance between the side surface of the target flow field and the outer edge of the canopy of the work-doing umbrella is not less than the head diameter of the work-doing umbrella, thereby ensuring that the work-doing umbrella model is immersed in the target flow field; wherein, the average distance between a certain plane of the target flow field (such as the inlet plane, the outlet plane, and the side surface) and the canopy of the work-doing umbrella can be the average value of the distance between each particle in the work-doing umbrella model and the plane of the target flow field.

[0078] Step 202: construct a bidirectional fluid-solid coupling system based on the work-doing umbrella model and the flow field model; wherein, in the bidirectional fluid-solid coupling system, there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model.

[0079] Among them, bidirectional fluid-solid coupling refers to the interaction between the fluid and the solid structure; when the fluid flow contacts the solid structure, the fluid will exert pressure and viscosity on the solid structure, causing the structure to deform; at the same time, the deformation of the solid structure will in turn affect the flow pattern of the fluid. In the scenario of the dynamic simulation of the working umbrella in this embodiment, the fluid is air and the solid structure is the working umbrella. In step 202, based on the above-established working umbrella model and flow field model, a bidirectional fluid-solid coupling system is constructed to achieve bidirectional fluid-solid coupling between the working umbrella and the fluid. For example, the above Figure 5 There is interaction between some fluid particles in the flow field model constructed in the target flow field and some particles of the work-doing umbrella. These two models constitute a two-way fluid-solid coupling system.

[0080] It can be understood that, as the simulation proceeds, the state of the work-doing umbrella changes continuously, the speed and position of the particles in the work-doing umbrella model also change continuously, the speed and position of the fluid particles in the flow field model also change continuously, and at the same time, as the target flow field is updated, some fluid particles in the flow field model will also change; accordingly, the particles and fluid particles that interact with each other in the work-doing umbrella model and the flow field model will also change, that is, in the process of simulation, the particles and fluid particles that interact with each other in the bidirectional fluid-solid coupling system will change.

[0081] Step 203: Perform simulation based on the bidirectional fluid-solid coupling system to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step to determine the characteristics of the work-doing umbrella during the dynamic opening and closing process.

[0082] The time step means dividing the dynamic opening and closing process of the active parachute to be simulated into multiple continuous time periods, each time period is a time step, and the length of the time period is the step length of the time step. For example, the process of the active parachute from a fully open state to a fully folded state can be divided into multiple time steps; for another example, a certain number of time steps can be pre-set; for another example, the process from the start of the simulation to the model entering a stable state can be divided into multiple time steps. The length of the time step is the time step, and the time step can be set as needed. The time steps corresponding to different time steps can be the same or different. In a possible implementation, the step size corresponding to each time step is determined by the density of fluid particles in the target flow field. As the simulation proceeds, the density of fluid particles in the target flow field will continue to change, that is, at different stages of the simulation, the density of fluid particles in the target flow field may be different. The step size corresponding to the time step at that stage can be determined according to the density of fluid particles in the target flow field at different stages, so that different time steps are used to solve the dynamic information of the work-doing parachute model and the dynamic information of the flow field model, thereby achieving a refined characterization of the dynamic changes of the parachute structure of the work-doing parachute.

[0083] Exemplarily, during the simulation process, as the time step continues to advance, the target flow field can be updated every preset number of time steps, so that the work-doing umbrella model is immersed in the target flow field through dynamic adjustment of the target flow field; wherein, during each update, the fluid particles to be deleted and added can be determined according to the position of each particle in the work-doing umbrella model in the current time step, thereby updating the target flow field, and accordingly, the above steps 201 and 202 are repeatedly executed to update the flow field model and the bidirectional fluid-solid coupling system based on the updated target flow field.

[0084] For example, the dynamic information may include information such as force, position, velocity and acceleration. Accordingly, the dynamic information of the work-doing parachute model includes: the force, velocity and position of each particle in the work-doing parachute model; the dynamic information of the flow field model includes: the force, velocity and position of the fluid particles in the flow field model. When solving the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, force analysis can be performed on each particle in the work-doing umbrella model, that is, each fluid particle in the flow field model, at each time step, to achieve force coupling between different component units; then, for any time step, a numerical integration method can be used to solve the acceleration of each particle in the work-doing umbrella model and the acceleration of each fluid particle in the flow field model based on the force analysis result; then, combined with the velocity and position of each particle in the work-doing umbrella model and the velocity and position of each fluid particle in the flow field model at the previous time step, the velocity and position of each particle in the work-doing umbrella model and the velocity and position of each fluid particle in the flow field model at this time step are determined; thereby achieving the coupled solution of fluid particles and particles in a bidirectional fluid-solid coupling system, and accurately updating the velocity and position of each particle in the work-doing umbrella model and the velocity and position of each fluid particle in the flow field model at each time step. Figure 6 A schematic diagram showing the simulation results of the dynamic change process of the parachute body of a working parachute according to an embodiment of the present disclosure is shown as follows: Figure 6 As shown, the states of the work-doing parachute corresponding to five different time steps (i.e., t=0.0s, t=1.0s, t=2.0s, t=10.0s, and t=11.5s) are shown. At different time steps, the position and velocity of each particle in the work-doing parachute model change.

[0085] In this step, the dynamic opening and closing process of the work umbrella is simulated based on the bidirectional fluid-solid coupling system established above. In the simulation process, a multiple time stepping strategy is adopted to perform coupling solution at each time step, so as to obtain the dynamic information of the work umbrella model and the dynamic information of the flow field model corresponding to each time step; based on the dynamic information of the work umbrella model corresponding to each time step, the dynamic behavior of the work umbrella can be analyzed, so as to determine the characteristics of the work umbrella in the dynamic opening and closing process; in addition, the flow field change around the work umbrella can be determined based on the dynamic information of the flow field model corresponding to each time step. Among them, the initial velocity of each fluid particle in the flow field model can be set according to the demand, so as to simulate different wind speed conditions, and realize the simulation of the work umbrella under different wind speed conditions, which can effectively give the stress state of the work umbrella during the opening and closing process under different wind speed conditions, so as to better assist the design and operation optimization of the land-based high-altitude wind power generation system, and promote the development of new energy development and other fields; compared with traditional simulation methods, the dynamic behavior of the work umbrella in a strong dynamic complex wind field can be simulated with high precision in a shorter time.

[0086] In the disclosed embodiment, a work-making parachute model and a flow field model around the work-making parachute are established; wherein the work-making parachute model is constructed based on the lumped mass method; the flow field model is constructed based on the smooth particle fluid dynamics method; based on the work-making parachute model and the flow field model, a two-way fluid-solid coupling system is constructed; wherein there is interaction between the partial component units corresponding to the work-making parachute model and the partial component units corresponding to the flow field model in the two-way fluid-solid coupling system; simulation is performed based on the two-way fluid-solid coupling system to solve the dynamic information of the work-making parachute model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-making parachute in the dynamic opening and closing process. Thus, the dynamic simulation of the work-making parachute in the parachute ladder type high-altitude wind power generation system is realized. In this way, a work parachute model is constructed based on the concentrated mass method, and a flow field model around the work parachute is constructed based on the smooth particle fluid dynamics method, so that the parachute body and the surrounding fluid of the work parachute in the two-way fluid-solid coupling system are both modeled by Lagrangian particles; then, a multiple time stepping strategy is adopted to couple and solve the two-way fluid-solid coupling system, and the dynamic information of the work parachute model and the dynamic information of the flow field model corresponding to each time step are solved, so as to determine the characteristics of the work parachute in the dynamic opening and closing process; compared with traditional simulation methods, the method in the embodiment of the present disclosure can complete a high-precision simulation of the dynamic behavior of the work parachute in a strong dynamic complex wind field in a shorter time, and in addition, the flow field changes around the work parachute can also be obtained. It can be applied to the analysis and prediction of the working conditions of the work parachute in actual engineering, so as to better assist the design and operation optimization of land-based high-altitude wind power generation systems and promote the development of new energy development and other fields.

[0087] The specific process of solving the dynamic information of the work-doing parachute model and the dynamic information of the flow field model corresponding to each time step based on the multiple time stepping strategy in the above step 203 is exemplarily described below.

[0088] Figure 7 A flow chart of a method for simulation based on a bidirectional fluid-solid coupling system according to an embodiment of the present disclosure is shown. The flow chart can be used as the above Figure 2 A possible implementation of step 203 is as follows: Figure 7 As shown, the following steps are included:

[0089] Step 701: at any time step, performing a penetration test between each fluid particle in the flow field model and each facet in the work-doing umbrella model, and between different facets in the work-doing umbrella model.

[0090] Among them, any surface element (also called unit surface element or structural surface element) is composed of multiple mass points in the work-doing parachute model. Figure 4As shown in FIG. 1 , a rectangular area composed of four particles is a surface element. At any time step, the position of each surface element can be determined based on the positions of the multiple particles that constitute the surface element.

[0091] Exemplarily, at any time step, a penetration detection is performed between each fluid particle in the flow field model and each face element in the work-doing umbrella model, which may include: for any fluid particle, the position of the fluid particle in the previous time step, the estimated position of the fluid particle in the current time step, and the estimated position of the face element in the work-doing umbrella model closest to the fluid particle in the current time step may be detected to determine whether there is a penetration depth between the fluid particle and the closest face element in the work-doing umbrella model, that is, to detect whether the position of the fluid particle in the previous time step and the position of the current time step are located on both sides of the estimated position of the closest face element in the current time step. If they are located on both sides, it indicates that after this time step, the fluid particle will penetrate the face element to a certain depth; if they are located on the same side, it indicates that after this time step, the fluid particle will still not penetrate the face element. Among them, the estimated position of the fluid particle in the current time step can be determined based on the position, velocity, and acceleration of the fluid particle in the previous time step, and the estimated position of the face element in the current time step can be determined based on the position, velocity, and acceleration of the particles constituting the face element in the previous time step.

[0092] Exemplarily, at any time step, performing a penetration detection on different face elements in the work-doing parachute model may include: for any face element, detecting the position of the face element at the previous time step, the estimated position of the face element at the current time step, and the estimated positions of other face elements in the work-doing parachute model that are closest to the face element at the current time step, and determining whether there is a penetration depth between the face element and the other closest face elements in the work-doing parachute model, that is, detecting whether the position of the face element at the previous time step and the position of the current time step are located on both sides of the estimated position of the other closest face element at the current time step; if they are located on both sides, it indicates that after this time step, the face element will penetrate the other face element to a certain depth; if they are located on the same side, it indicates that after this time step, the face element will still not penetrate the other face element.

[0093] Step 702: Based on the mold penetration detection result, determine the fluid particles and particles that interact with each other, and the different particles that interact with each other in the bidirectional fluid-solid coupling system.

[0094] As the simulation proceeds, the interacting fluid particles and particles, as well as the different interacting particles in the bidirectional fluid-solid coupling system may change. In step 702, at any time step, the interacting fluid particles and particles, as well as the different interacting particles in the bidirectional fluid-solid coupling system are determined based on the penetration detection result of the current time step.

[0095] Among them, the penetration test result includes the existence of penetration depth and the non-existence of penetration depth. Through the above step 701, each fluid particle in the flow field model is traversed, and for any fluid particle, it is checked whether there is a penetration depth between it and the nearest surface element in the work-doing umbrella model. If so, the fluid particle and the particles constituting the surface element are determined as fluid particles and particles that interact with each other in the two-way fluid-solid coupling system; correspondingly, each surface element in the work-doing umbrella model is traversed, and for any surface element, it is checked whether there is a penetration depth between it and the nearest other surface elements in the work-doing umbrella model. If so, the particles constituting the surface element and the particles constituting the other surface elements are determined as different particles that interact with each other in the two-way fluid-solid coupling system.

[0096] Step 703: Calculate the force between the interacting fluid particles and the mass points, and the force between the interacting different mass points, by using a penalty function.

[0097] For example, at any time step, the force between the interacting fluid particles and the particles in the bidirectional fluid-solid coupling system is calculated by the penalty function, and then the force can be introduced as a penalty force term, i.e., an external force term, when performing force analysis on the interacting fluid particles and the particles.

[0098] For example, at any time step, the force between different interacting particles in a bidirectional fluid-solid coupling system is calculated by a penalty function, and then the force can be introduced as a penalty force term, i.e., an external force term, when performing force analysis on different interacting particles.

[0099] Among them, the penalty function Generally, it has the following form:

[0100]

[0101] Where: k penalty is the penalty coefficient, and also the stiffness coefficient of the work parachute surface element. The value of this coefficient can be set according to the demand. l is the penetration depth of the fluid particles on the surface element or the penetration depth of one surface element on another surface element. The penetration depth can be determined based on the positions of the two. is the outward normal unit vector of the penetrated surface element.

[0102] In this way, through the above steps 701-703, at any time step, the modeling of the interaction contact force between the two is realized by using the penetration detection combined with the penalty function. Specifically, the fluid-solid coupling calculation of the fluid and the work-doing umbrella (i.e., the penetration detection of the fluid particles and the work-doing umbrella surface elements and the force between the fluid particles and the particle points) and the self-contact analysis of the work-doing umbrella canopy (i.e., the penetration detection between different surface elements of the work-doing umbrella and the force between the particle points constituting different surface elements) are all performed in this way.

[0103] Step 704: Based on the interaction forces between the interacting fluid particles and the mass points and the interaction forces between the fluid particles in the flow field model, determine the dynamic information of the flow field model corresponding to the time step.

[0104] In this step, a force analysis is performed on each fluid particle in the bidirectional fluid-solid coupling system at any time step, wherein, for any fluid particle, if there is a penetration depth between the fluid particle and the surface element, that is, the above step calculates the force between the fluid particle and the particle through the penalty function, then the force is used as an external force term, and the surface force and volume force of the fluid particle are calculated, which includes the force between the fluid particle and other fluid particles, thereby completing the force analysis of the fluid particle; for any fluid particle, if there is no penetration depth between the fluid particle and the surface element, that is, the above step does not calculate the force between the fluid particle and the particle through the penalty function, then the surface force and volume force of the fluid particle are calculated, that is, the force between the fluid particle and other fluid particles, thereby completing the force analysis of the fluid particle. Furthermore, after completing the force analysis of each fluid particle in the flow field model, numerical integration is performed to determine the dynamic information of the flow field model corresponding to the time step, that is, the position and velocity of each fluid particle in the flow field model at the time step can be determined. For example, the Velocity-Verlet integral can be used to calculate Newton's second law, and the position and velocity of each fluid particle in the flow field model can be updated at each time step; wherein the basic idea of ​​the Velocity-Verlet method is to approximate the motion of particles through Taylor series expansion.

[0105] In a possible implementation, the dynamic information of the flow field model corresponding to the time step is determined based on the interaction force between the interacting fluid particles and the mass points and the interaction force between the fluid particles in the flow field model, including: performing a neighborhood search for each fluid particle in the flow field model, and updating the density attribute of the fluid particle according to the neighborhood search result; updating the pressure attribute of the fluid particle according to the density attribute of the fluid particle; determining the interaction force between the fluid particle and other fluid particles based on the current velocity of the fluid particle, the density attribute, the pressure attribute, and the viscosity attribute; determining the dynamic information of the fluid particle corresponding to the time step based on the interaction force between the fluid particle and other fluid particles and the interaction force between the fluid particle and the mass points in the work-doing umbrella model. Exemplarily, for each fluid particle in the flow field model, a neighborhood search is performed to search for other fluid particles within its neighborhood, and the neighborhood search result is the other fluid particle, and then the density attribute of the fluid particle is updated; Exemplarily, the pressure attribute of the fluid particle can be updated according to the density attribute of the fluid particle and the distribution of other fluid particles in its neighborhood.

[0106] As an example, at any time step, for each fluid particle (unit mass) in the flow field model, the force equation of the fluid particle can be expressed as:

[0107]

[0108] Where: is the acceleration of the fluid particles; is the external force term of the acceleration of the fluid particle, that is, the acceleration term generated by the gravitational acceleration of the fluid particle and the force between the fluid particle and the particle calculated by the penalty function; p is the pressure of the fluid particle, that is, the pressure property of the fluid particle; ρ is the equivalent density of the fluid particle, that is, the density property of the fluid particle; μ is the viscosity coefficient of the fluid, that is, the viscosity property of the fluid particle; is the current velocity of the fluid particles. The pressure term that constitutes the acceleration, The viscous term that constitutes the acceleration, and both are the surface forces on the fluid particles.

[0109] The position of the fluid particle can be expressed as:

[0110]

[0111] Among them, v n ″ represents the velocity of the fluid particle at the nth time step, x′ n ′ represents the position of the fluid particle at the nth time step, x′ n ' +1 represents the position of the fluid particle at the n+1th time step, and Δt represents a time step.

[0112] The velocity of the fluid particle can be expressed as:

[0113]

[0114] Among them, v n ″ represents the velocity of the fluid particle at the nth time step, a′ n ′ represents the acceleration of the fluid particle at the nth time step, a′ n ' +1 represents the acceleration of the fluid particle at the n+1th time step, v′ n ' +1 represents the velocity of the fluid particle at the n+1th time step, and Δt represents a time step.

[0115] Step 705: Determine the dynamic information of the work-doing umbrella model corresponding to the time step based on the forces between the interacting fluid particles and the particles, the forces between the interacting different particles, and the forces of the mechanical units corresponding to the particles in the work-doing umbrella model.

[0116] In this step, a force analysis is performed on each particle in the bidirectional fluid-solid coupling system at any time step, wherein, for any particle, if there is a penetration depth between the face element where the particle is located and other face elements, that is, the above step calculates the force between the particle and the particles of the other face elements through the penalty function, then the force is used as an external force term; if there is a penetration depth between the fluid particle and the face element where the particle is located, that is, the above step calculates the force between the fluid particle and the particle through the penalty function, then the force is used as an external force term; if the particle has both of the above two penetration depths, then the force between the particle and the particles of the other face elements and the force between the fluid particle and the particle are used as external force terms; if neither of the above two penetration depths exists, the external force term is zero. On the basis of determining the external force term, the force of the mechanical unit corresponding to the particle is calculated, thereby completing the force analysis of the particle. Furthermore, after completing the above force analysis of each particle in the work-doing parachute model, numerical integration is performed to determine the dynamic information of the work-doing parachute model corresponding to the time step, that is, the position and velocity of each particle in the work-doing parachute model at the time step can be determined. For example, Velocity-Verlet integration can be used to calculate Newton's second law, and the position and velocity of each particle in the work-doing parachute model can be updated at each time step;

[0117] Figure 8 A schematic diagram showing a working umbrella in a closed and opened state according to an embodiment of the present disclosure is shown in FIG. Figure 8 As shown in FIG. 1 , under the influence of wind speed, the working parachute gradually changes from a closed state to an open state. As the shape of the working parachute changes, the force and dynamic information of the same particle in the working parachute change.

[0118] In a possible implementation, determining the dynamic information of the work-doing umbrella model corresponding to the time step based on the force between the interacting fluid particles and the mass points, the force between the interacting different mass points, and the force of the mechanical unit corresponding to each mass point in the work-doing umbrella model may include: for each mass point in the work-doing umbrella model, based on the force of the extension spring borne by the mass point, the force of the shear spring borne by the mass point, and the force of the bending spring borne by the mass point, determining the force between the mass point and the fluid particles in the flow field model, and the force between the mass point and the mass points in the work-doing umbrella model; determining the dynamic information of the mass point corresponding to the time step based on the force of the mechanical unit corresponding to the mass point, the force between the mass point and the fluid particles in the flow field model, and the force between the mass point and the mass points in the work-doing umbrella model. Exemplarily, the force of the tension spring borne by the mass point, the force of the shear spring borne by the mass point, and the force of the bending spring borne by the mass point are calculated using Hooke's law based on the positions of other mass points connected to the mass point on the corresponding springs and the position of the mass point.

[0119] As an example, at any time step, for each mass point (unit volume) in the work parachute model, the force equation of the mass point can be expressed as:

[0120]

[0121] Where: m is the equivalent density of the particle; is the acceleration of the particle; is the external force item borne by the particle, namely, the gravity of the particle and the force between the particle and the fluid particles calculated by the penalty function, and the force between the particle and the particles on other surface elements; is the tensile spring force borne by the mass point; is the shear spring force borne by the mass point; is the bending spring force borne by the mass point.

[0122] The position of the particle can be expressed as:

[0123]

[0124] Among them, v n ′ represents the velocity of the particle at the nth time step, x′ n represents the position of the particle at the nth time step, x′ n+1 represents the position of the particle at the n+1th time step, and Δt represents a time step.

[0125] The velocity of the particle can be expressed as:

[0126]

[0127] Among them, v n ′ represents the velocity of the particle at the nth time step, a′ n represents the acceleration of the particle at the nth time step, a′ n+1 represents the acceleration of the particle at the n+1th time step, v′ n+1 represents the velocity of the particle at the n+1th time step, and Δt represents a time step.

[0128] For example, Fig. 9 A flow chart of a simulation according to an embodiment of the present disclosure is shown as follows: Fig. 9 As shown, the flexible structure model (i.e., the work umbrella model) is established through step 1.1, and the flow field model (i.e., the flow field model around the work umbrella) is established through step 1.2 (i.e., the above step 201), wherein the lumped mass method is used to establish the flexible structure model, the SPH method is used to establish the fluid particle micro-element model, and the range and boundary conditions of the target flow field are set. Then, the fluid-solid model is adapted and coupled through step 2, specifically, the penalty function method can be used as the force coupling method, the Velocity-Verlet method can be used as the numerical integration method, and the fluid state in the flow field and the structural particle information are updated; wherein, the penalty function method specifically includes: performing neighborhood retrieval for each fluid particle, updating the density attribute of the fluid particle, updating the pressure attribute of the fluid particle according to the density attribute of the fluid particle, performing mold penetration detection between each fluid particle and the flexible structure to impose mold penetration penalty, and updating the force of the fluid particle and the structural particle. Then, step 3 is used to perform a dynamic simulation of the work-doing parachute structure under the action of air load. During the simulation process, the above steps are repeated until the simulation is completed, thereby obtaining the fluid state in the flow field at different time steps and the particle information in the flexible structure model (i.e., the above steps 202 and 203) to analyze the dynamic behavior of the work-doing parachute.

[0129] Based on the same inventive concept of the above method embodiments, the embodiments of the present disclosure also provide a device for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling, which can be used to execute the technical solution described in the above method embodiments.

[0130] Fig.10 The structure diagram of a dynamic opening and closing characteristic simulation device of a flexible umbrella structure with bidirectional fluid-solid coupling according to an embodiment of the present disclosure is shown, which is applied to the dynamic simulation of a working umbrella in an umbrella ladder type high-altitude wind power generation system, such as Fig.10As shown, the device includes: a modeling module 1001, which is used to establish a work-doing umbrella model and a flow field model around the work-doing umbrella; wherein the work-doing umbrella model is constructed based on a concentrated mass method; the flow field model is constructed based on a smooth particle fluid dynamics method; the modeling module 1001 is also used to construct a two-way fluid-solid coupling system based on the work-doing umbrella model and the flow field model; wherein there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model in the two-way fluid-solid coupling system; a simulation module 1002 is used to perform simulation based on the two-way fluid-solid coupling system, solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-doing umbrella in the dynamic opening and closing process.

[0131] In the disclosed embodiment, a work-making parachute model and a flow field model around the work-making parachute are established; wherein the work-making parachute model is constructed based on the lumped mass method; the flow field model is constructed based on the smooth particle fluid dynamics method; based on the work-making parachute model and the flow field model, a two-way fluid-solid coupling system is constructed; wherein there is interaction between the partial component units corresponding to the work-making parachute model and the partial component units corresponding to the flow field model in the two-way fluid-solid coupling system; simulation is performed based on the two-way fluid-solid coupling system to solve the dynamic information of the work-making parachute model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-making parachute in the dynamic opening and closing process. Thus, the dynamic simulation of the work-making parachute in the parachute ladder type high-altitude wind power generation system is realized. In this way, a work parachute model is constructed based on the concentrated mass method, and a flow field model around the work parachute is constructed based on the smooth particle fluid dynamics method, so that the parachute body and the surrounding fluid of the work parachute in the two-way fluid-solid coupling system are both modeled by Lagrangian particles; then, a multiple time stepping strategy is adopted to couple and solve the two-way fluid-solid coupling system, and the dynamic information of the work parachute model and the dynamic information of the flow field model corresponding to each time step are solved, so as to determine the characteristics of the work parachute in the dynamic opening and closing process; compared with traditional simulation methods, the method in the embodiment of the present disclosure can complete a high-precision simulation of the dynamic behavior of the work parachute in a strong dynamic complex wind field in a shorter time, and in addition, the flow field changes around the work parachute can also be obtained. It can be applied to the analysis and prediction of the working conditions of the work parachute in actual engineering, so as to better assist the design and operation optimization of land-based high-altitude wind power generation systems and promote the development of new energy development and other fields.

[0132] In a possible implementation, the constituent units of the work-doing umbrella model include multiple mass points; the modeling module 1001 is further used to: use the lumped mass method to describe the work-doing umbrella to obtain the multiple mass points; for any mass point among the multiple mass points, determine the mechanical unit corresponding to the mass point, wherein the mechanical unit is used to connect the mass point with at least one other mass point among the multiple mass points; the mechanical unit includes: one or more of a bending spring, a shear spring and a tension spring; based on the multiple mass points and the mechanical units corresponding to each of the multiple mass points, establish the work-doing umbrella model.

[0133] In a possible implementation, the component units of the flow field model include multiple fluid particles; the modeling module 1001 is also used to: determine the target flow field based on the work-doing umbrella model so that the work-doing umbrella model is immersed in the target flow field; use the smooth particle fluid dynamics method to determine the multiple fluid particles in the target flow field; and establish the flow field model based on the multiple fluid particles.

[0134] In a possible implementation, the simulation module 1002 is further used to: perform a penetration test between each fluid particle in the flow field model and each surface element in the work-doing umbrella model, and between different surface elements in the work-doing umbrella model at any time step, wherein any surface element is composed of a plurality of particles in the work-doing umbrella model; determine the fluid particles and particles that interact with each other, and the different particles that interact with each other in the bidirectional fluid-solid coupling system based on the penetration test result; calculate the force between the fluid particles and particles that interact with each other, and the force between the different particles that interact with each other through a penalty function; determine the dynamic information of the flow field model corresponding to the time step based on the force between the fluid particles and particles that interact with each other, and the force between the fluid particles in the flow field model; determine the dynamic information of the work-doing umbrella model corresponding to the time step based on the force between the fluid particles and particles that interact with each other, the force between the different particles that interact with each other, and the force of the mechanical unit corresponding to each particle in the work-doing umbrella model.

[0135] In a possible implementation, the simulation module 1002 is also used to: perform a neighborhood search for each fluid particle in the flow field model, and update the density attribute of the fluid particle according to the neighborhood search result; update the pressure attribute of the fluid particle according to the density attribute of the fluid particle; determine the force between the fluid particle and other fluid particles based on the current velocity of the fluid particle, the density attribute, the pressure attribute, and the viscosity attribute; determine the dynamic information of the fluid particle corresponding to the time step based on the force between the fluid particle and other fluid particles and the force between the fluid particle and the particle in the work-doing umbrella model.

[0136] In a possible implementation, the simulation module 1002 is further used to: for each particle in the work-doing umbrella model, determine the force of the mechanical unit corresponding to the particle based on the force of the tension spring borne by the particle, the force of the shear spring borne by the particle, and the force of the bending spring borne by the particle; determine the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particles in the work-doing umbrella model; determine the dynamic information of the particle corresponding to the time step based on the force of the mechanical unit corresponding to the particle, the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particles in the work-doing umbrella model.

[0137] In a possible implementation, the step size corresponding to each time step is determined by the density of fluid particles in the target flow field.

[0138] In some embodiments, the functions or modules included in the device provided by the embodiments of the present disclosure can be used to execute the method described in the above method embodiments. The specific implementation can refer to the description of the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0139] The embodiment of the present disclosure also provides a computer-readable storage medium on which computer program instructions are stored, and the computer program instructions implement the above method when executed by a processor. The computer-readable storage medium can be a volatile or non-volatile computer-readable storage medium.

[0140] An embodiment of the present disclosure further proposes an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to implement the above method when executing the instructions stored in the memory.

[0141] The embodiments of the present disclosure also provide a computer program product, including a computer-readable code, or a non-volatile computer-readable storage medium carrying the computer-readable code. When the computer-readable code runs in a processor of an electronic device, the processor in the electronic device executes the above method.

[0142] Fig.11 1 is a block diagram of an electronic device 1900 according to an embodiment of the present disclosure. For example, the electronic device 1900 may be provided as a server or a terminal device. Fig.11 , the electronic device 1900 includes a processing component 1922, which further includes one or more processors, and a memory resource represented by a memory 1932 for storing instructions executable by the processing component 1922, such as an application. The application stored in the memory 1932 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 1922 is configured to execute instructions to perform the above method.

[0143] The electronic device 1900 may also include a power supply component 1926 configured to perform power management of the electronic device 1900, a wired or wireless network interface 1950 configured to connect the electronic device 1900 to a network, and an input / output interface 1958 (I / O interface). The electronic device 1900 may operate based on an operating system stored in the memory 1932, such as Windows Server 2003. TM , Mac OS X TM , Unix TM ,Linux TM , FreeBSD TM or similar.

[0144] In an exemplary embodiment, a non-volatile computer-readable storage medium is also provided, such as a memory 1932 including computer program instructions, which can be executed by the processing component 1922 of the electronic device 1900 to perform the above method.

[0145] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0146] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0147] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0148] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0149] Various aspects of the present disclosure are described herein with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer-readable program instructions.

[0150] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processor of the computer or other programmable data processing device, a device that implements the functions / actions specified in one or more boxes in the flowchart and / or block diagram is generated. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause the computer, programmable data processing device, and / or other equipment to work in a specific manner, so that the computer-readable medium storing the instructions includes a manufactured product, which includes instructions for implementing various aspects of the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0151] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operating steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0152] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of the module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0153] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for simulating the dynamic opening and closing characteristics of a flexible umbrella structure with bidirectional fluid-solid coupling, which is applied to the dynamic simulation of a working umbrella in an umbrella ladder type high-altitude wind power generation system, and is characterized in that: The method comprises: Establishing a work-doing parachute model and a flow field model around the work-doing parachute; wherein the work-doing parachute model is constructed based on a lumped mass method; and the flow field model is constructed based on a smoothed particle fluid dynamics method; Based on the work-doing umbrella model and the flow field model, a bidirectional fluid-solid coupling system is constructed; wherein, in the bidirectional fluid-solid coupling system, there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model; Based on the bidirectional fluid-solid coupling system, simulation is performed to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-doing umbrella in the dynamic opening and closing process.

2. The method according to claim 1, characterized in that The component unit of the work-doing parachute model includes a plurality of mass points; The method of establishing a work-doing umbrella model comprises: The work-doing parachute is described by using the concentrated mass method to obtain the multiple mass points; For any mass point among the plurality of mass points, determine a mechanical unit corresponding to the mass point, wherein the mechanical unit is used to connect the mass point with at least one other mass point among the plurality of mass points; the mechanical unit includes: one or more of a bending spring, a shear spring and a tension spring; The work-doing umbrella model is established based on the multiple mass points and the mechanical units corresponding to each of the multiple mass points.

3. The method according to claim 2, characterized in that The component units of the flow field model include a plurality of fluid particles; The step of establishing a flow field model around the working parachute comprises: Based on the work-doing umbrella model, determining a target flow field so that the work-doing umbrella model is immersed in the target flow field; Using the smoothed particle fluid dynamics method, determining a plurality of fluid particles within the target flow field; The flow field model is established based on the multiple fluid particles.

4. The method according to claim 3, characterized in that The simulation based on the bidirectional fluid-solid coupling system is performed to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, including: At any time step, performing a penetration test between each fluid particle in the flow field model and each surface element in the work-doing umbrella model, and between different surface elements in the work-doing umbrella model, wherein any surface element is composed of a plurality of particle points in the work-doing umbrella model; Based on the mold penetration detection result, determining the fluid particles and particles that interact with each other in the bidirectional fluid-solid coupling system, as well as the different particles that interact with each other; Calculating the force between the interacting fluid particles and the mass points, and the force between the interacting different mass points, by using a penalty function; Determining the dynamic information of the flow field model corresponding to the time step based on the interaction forces between the interacting fluid particles and the mass points and the interaction forces between the fluid particles in the flow field model; Based on the forces between the interacting fluid particles and the mass points, the forces between the interacting different mass points, and the forces of the mechanical units corresponding to the mass points in the work-doing umbrella model, the dynamic information of the work-doing umbrella model corresponding to the time step is determined.

5. The method according to claim 4, characterized in that The determining the dynamic information of the flow field model corresponding to the time step based on the interaction force between the interacting fluid particles and the mass points and the interaction force between the fluid particles in the flow field model includes: For each fluid particle in the flow field model, a neighborhood search is performed, and a density attribute of the fluid particle is updated according to the neighborhood search result; According to the density attribute of the fluid particle, the pressure attribute of the fluid particle is updated; Determine the force between the fluid particle and other fluid particles based on the current velocity of the fluid particle, the density attribute, the pressure attribute, and the viscosity attribute; Based on the interaction force between the fluid particle and other fluid particles and the interaction force between the fluid particle and the mass point in the work-doing umbrella model, the dynamic information of the fluid particle corresponding to the time step is determined.

6. The method according to claim 4, characterized in that The determining of the dynamic information of the work-doing umbrella model corresponding to the time step based on the force between the interacting fluid particles and the mass points, the force between the interacting different mass points, and the force of the mechanical unit corresponding to each mass point in the work-doing umbrella model comprises: For each mass point in the work-doing umbrella model, based on the force of the tension spring borne by the mass point, the force of the shear spring borne by the mass point, and the force of the bending spring borne by the mass point, the force of the mechanical unit corresponding to the mass point is determined; Determine the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particle in the work-doing umbrella model; Based on the force of the mechanical unit corresponding to the particle, the force between the particle and the fluid particles in the flow field model, and the force between the particle and the particle in the work-doing umbrella model, the dynamic information of the particle corresponding to the time step is determined.

7. The method according to claim 3, characterized in that The step size corresponding to each time step is determined by the density of fluid particles in the target flow field.

8. A dynamic opening and closing characteristic simulation device of a flexible umbrella structure with bidirectional fluid-solid coupling, which is applied to the dynamic simulation of a working umbrella in an umbrella ladder type high-altitude wind power generation system, and is characterized in that: The device comprises: A modeling module, used to establish a work-doing parachute model and a flow field model around the work-doing parachute; wherein the work-doing parachute model is constructed based on a lumped mass method; and the flow field model is constructed based on a smoothed particle fluid dynamics method; The modeling module is further used to construct a bidirectional fluid-solid coupling system based on the work-doing umbrella model and the flow field model; wherein, in the bidirectional fluid-solid coupling system, there is interaction between some component units corresponding to the work-doing umbrella model and some component units corresponding to the flow field model; A simulation module is used to perform simulation based on the bidirectional fluid-solid coupling system to solve the dynamic information of the work-doing umbrella model and the dynamic information of the flow field model corresponding to each time step, so as to determine the characteristics of the work-doing umbrella during the dynamic opening and closing process.

9. An electronic device, characterized in that: include: processor; a memory for storing processor-executable instructions; The processor is configured to implement the method described in any one of claims 1 to 7 when executing the instructions stored in the memory.

10. A non-volatile computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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