29 results about "Incompressible flow" patented technology

The present invention discloses a valve assembly comprising a seat ring, a valve plate assembly movable between a sealed position within the seat ring and an open position outside the seat ring. A fitting can pass through the valve plate, and / or a sensor assembly can extend through the fitting with a sensor mounted below the valve plate assembly. The sensor assembly provides enhanced monitoring capabilities by being positioned in the incompressible fluid column below the valve plate assembly, ensuring accurate sensing of relevant parameters. This configuration allows for efficient and reliable operation of the valve assembly, enhancing its performance and functionality in various applications.

The invention discloses an incompressible fluid flow numerical solution method based on deep learning and spectral differentiation, and belongs to the technical field of fluid mechanics. The problems that when a neural network is used for solving high Reynolds number flow, calculation burden of a high-order derivative is too heavy, long-time simulation precision of unsteady flow such as vortex shedding is attenuated, adaptability of complex boundaries such as a channel wall face and a periodic boundary group is poor, and a hardware video memory is limited in solving of large-scale flow such as three-dimensional turbulent flow are solved. The method specifically comprises the steps of adopting a solution of a memory-saving reversible neural network approximation equation; deducing a space-time Chebyshev differential matrix to quickly and accurately calculate a space-time partial derivative; a unified spectral discrete format is adopted in the space-time dimension, global space-time information is integrated, and the non-local effect of the flow field is considered. Through fusion of spectral differential and a reversible neural network, a loss function composed of a residual error of a Navier-Stokes equation and an initial boundary condition matching error is optimized, incompressible fluid flow can be efficiently solved on equipment with a limited memory, and complex boundary conditions are adapted.

A landing gear assembly for rotorcraft includes a shock absorber, a ground support assembly and an airframe linkage assembly. The shock absorber includes a force sensor to detect a pressure of an incompressible fluid within the shock absorber and a temperature sensor to detect a temperature of the fluid. The ground support assembly is linked to the shock absorber and includes an axle and a ground contact element movable in relation to the axle. The linkage assembly is linked to the shock absorber and / or the ground support assembly and includes a position sensor to detect movement of the axle between compressed and uncompressed conditions of the shock absorber. Various rotorcraft include one, two, three or more landing gear assemblies and an attitude control system. Various rotorcraft methods process sensor signals from one, two, three or more landing gear assemblies at the attitude control system to provide various rotorcraft functions.

The application discloses a kind of double box girder flow field dynamics modal and flow stability analysis method and system, belong to bridge engineering field.This method first establishes double box girder flow field model by computational fluid dynamics, solves the momentum equation and continuity equation of two-dimensional incompressible flow;Dynamic modal decomposition is carried out again, and eigenvalue, characteristic mode and other information are obtained;Finally, based on linear stability theory, the flow field component is expressed as the sum of steady-state solution and disturbance term, and the global linear flow stability equation is obtained by substituting into the equation, and the flow stability is analyzed by discrete.This method can accurately extract the modal characteristics of each order, providing a scientific basis for wind-induced vibration analysis of double box girder, and has important application value.The method of the application occupies less computing resources, has high numerical accuracy, and can be further expanded to higher precision calculation model according to computing resources, and is suitable for application in actual bridge engineering.

Systems and methods for digitally simulating a fluid flow in a three-dimensional computer-aided design (CAD) model of a simulation space include digitally simulating movement of one or more digital particles representing the fluid from one or more first voxels in a mesh to one or more second voxels in the mesh, performing one or more interaction operations on the one or more digital particles at the one or more second voxels to determine a distribution of the one or more digital particles. A first quantity represented by the distribution of the one or more digital particles is based on a temperature and a pressure at the one or more second voxels and a reference fluid density. A second quantity represented by the distribution of the one or more digital particles is based on the reference fluid density, velocities of the one or more digital particles, and a mean fluid velocity.

A downhole motor control system may identify a downhole compressible density of a drilling fluid using a downhole temperature and a downhole pressure of the drilling fluid, the drilling fluid including an incompressible portion and a compressible portion, the drilling fluid flowing downhole with a downhole compressible flow component and an incompressible flow component. A downhole motor control system may determine the downhole compressible flow component using the downhole compressible density, a surface compressible density of the compressible portion at a surface location, and a surface compressible flow component of the compressible portion at the surface location. A downhole motor control system may identify a downhole compressible fraction of the drilling fluid based on the downhole compressible flow component and the incompressible flow component. A downhole motor control system may generate a composite flow rate of the drilling fluid based on the incompressible flow component and the downhole compressible fraction.

The present application relates to the field of supply chain logistics scheduling, and provides a supply chain cargo transfer method and system based on multi-agent cooperation, which comprises the following steps: a center node constructs an incompressible fluid continuity equation with a diffusion term, obtains a continuous global navigation field by solving, and distributes the field to edge agents; the edge agents analyze the field gradient vector based on the field, convert the field gradient vector into a speed control instruction, and use the speed control instruction to drive continuous movement; the edge agents detect local physical disturbances, convert the local physical disturbances into field correction parameters, and upload the field correction parameters; the center node takes the field correction parameters as a field update source, substitutes the field correction parameters into a solving process, updates the continuous global navigation field, and distributes the field to form a closed-loop regulation and control. Thus, the instruction confrontation and oscillation between the center discrete path and the edge continuous potential field are eliminated, macro flow control is realized in a flexible and smooth manner, and the system robustness is greatly improved.

A downhole motor control system may identify a downhole compressible density of a drilling fluid using a downhole temperature and a downhole pressure of the drilling fluid, the drilling fluid including an incompressible portion and a compressible portion, the drilling fluid flowing downhole with a downhole compressible flow component and an incompressible flow component. A downhole motor control system may determine the downhole compressible flow component using the downhole compressible density, a surface compressible density of the compressible portion at a surface location, and a surface compressible flow component of the compressible portion at the surface location. A downhole motor control system may identify a downhole compressible fraction of the drilling fluid based on the downhole compressible flow component and the incompressible flow component. A downhole motor control system may generate a composite flow rate of the drilling fluid based on the incompressible flow component and the downhole compressible fraction.

Systems and methods for digitally simulating a fluid flow in a three-dimensional computer-aided design (CAD) model of a simulation space include digitally simulating movement of one or more digital particles representing the fluid from one or more first voxels in a mesh to one or more second voxels in the mesh, performing one or more interaction operations on the one or more digital particles at the one or more second voxels to determine a distribution of the one or more digital particles. A first quantity represented by the distribution of the one or more digital particles is based on a temperature and a pressure at the one or more second voxels and a reference fluid density. A second quantity represented by the distribution of the one or more digital particles is based on the reference fluid density, velocities of the one or more digital particles, and a mean fluid velocity.

The invention relates to an actuation device for actuating a vehicle function, comprising: a support device; a fluid pad assembly having at least one fluid pad protruding from the carrier device, the fluid pad including at least one resilient enclosure and a first volume having an incompressible fluid at least partially surrounded by the resilient enclosure; and at least one hydropneumatic accumulator fluidly connected to the first volume, the at least one elastic enclosure absorbing an actuation force of the driver's foot in multiple directions such that a deformation of the at least one elastic enclosure caused by the actuation force results in a reduction in the enclosed first volume and an increase in the internal pressure, the at least one sensor unit detects a deformation of the at least one elastic enclosure caused by the actuating force and forwards it to the at least one evaluation and control unit electrically coupled to the at least one sensor unit, and at least one control unit which generates at least one control signal for controlling the vehicle function as a function of a deformation of the elastic enclosure detected by the at least one sensor unit and caused by the actuating force.

The invention discloses an asynchronous GMRES precondition method for AI acceleration of a pressure Poisson equation in incompressible flow numerical calculation, and belongs to the field of computational fluid mechanics. Aiming at the calculation bottleneck of a traditional GMRES method when a pressure Poisson equation is solved, the method adopts an asynchronous parallel AI precondition framework, neural network training and flow field solving are decoupled, and concurrent execution is achieved. The solver thread performs real-time inference by using the current model, and provides high-quality initial guess; the weight is optimized in the background of the trainer thread, and the lagging is tolerated by using the flow field time coherence. Experimental results show that the method shortens the solving time by 67%-82% on the premise of ensuring convergence precision, and is suitable for large-scale fluid simulation.

The invention discloses a method and a system for analyzing dynamic modality and flow stability of a flow field around a double-box girder, and belongs to the field of bridge engineering. The method comprises the following steps: firstly, establishing a double-box girder surrounding flow field model through computational fluid dynamics, and solving a momentum equation and a continuity equation of a two-dimensional incompressible flow; performing dynamic mode decomposition to obtain information such as characteristic values and characteristic modes; and finally, based on a linear stability theory, representing a flow field component as a sum of a steady-state solution and a disturbance term, substituting the sum into the equation to obtain a global linear flow stability equation, and analyzing the flow stability through discretization. The method can accurately extract modal features of each order, provides a scientific basis for double-box girder wind-induced vibration analysis, and has important application value. The method occupies few computing resources, is high in numerical precision, can be further expanded to a computing model with higher precision according to the computing resources, and is suitable for being applied to actual bridge engineering.

A computer system for digital simulation of pseudo-incompressible fluid flow in a computer-aided design model is disclosed. Systems and methods for digital simulation of fluid flow in a three-dimensional computer-aided design (CAD) model of a simulation space include: digitally simulating movement of one or more digital particles representing a fluid from one or more first voxels in a grid to one or more second voxels in the grid; one or more interaction operations are performed on the one or more digital particles at the one or more second voxels to determine a distribution of the one or more digital particles. The first quantity represented by the distribution of the one or more digital particles is based on the temperature and pressure at the one or more second voxels and the reference fluid density. The second quantity represented by the distribution of the one or more digital particles is based on the reference fluid density, the velocity of the one or more digital particles, and the average fluid velocity.

Disclosed herein is a system for generating neutrons with thermal fusion, composition for use in the same, and method of using the same. The system comprises a crucible, the crucible having a quantum incompressible fluid and a gas bubble therein, a piston having an end submerged within the quantum incompressible fluid, and a controller coupled to the piston configured to drive the piston to generate an acoustic resonance in the quantum incompressible fluid.

A downhole power generation system (10) comprising a pressure chamber assembly (12) having a first movable element (14, 48, 49) which at least partially encloses a first variable volume chamber (V1A) and a second movable element (16, 48', 49') which at least partially encloses a second variable volume chamber (V1B), each movable element (14, 48, 49, 16, 48', 49') having an exterior surface and an interior surface, and the first and second variable volume chambers (V1A, V1B) being connected by a conduit (18) so that they together enclose a closed volume (V1) containing an incompressible fluid, the conduit (18) providing a path for flow of the incompressible fluid between the first variable volume chamber (V1A) and the second variable volume chamber (V1B) when the first and second movable elements (14, 48, 49, 16, 48', 49') move so that one of the first or second variable volume chamber (V1A, V1B) contracts and the other expands, the system further comprising a generator device (20) which is located in the conduit (18), and which is configured to use the flow of incompressible fluid along the conduit (18) to generate power.

The invention provides a propeller hydrodynamic force rapid estimation method, device, equipment and medium, and the method comprises the steps: adopting a plurality of curved surfaces which are coaxial with a propeller and have different radiuses, cutting a single blade profile of a three-dimensional geometric model of the propeller, and forming blade sections with different radiuses, obtaining a group of quasi two-dimensional curved surface calculation models; performing rapid grid division on each quasi-two-dimensional curved surface calculation area containing the propeller tangent plane, and setting a flow field boundary condition and a flow field initial condition for the divided calculation area; on the basis of set conditions, an incompressible flow pressure correction method is adopted for unsteady numerical calculation, and axial force and circumferential force borne by the curved surface airfoil profile in each divided calculation area under different working conditions are obtained through solving; based on different cross section positions and axial force and circumferential force on each cross section, total thrust and total torque borne by blades of the propeller thruster are calculated through radial integral approximation, so that the problems that mutual influence of flow fields in complex thruster design is difficult to evaluate, and efficiency and precision of a traditional method are unbalanced are solved.

The application discloses a flow-solid coupling method for simulating autonomous swimming of flexible organisms based on an improved immersed boundary method, and the method comprises the following steps: A, initial parameters are specified at each interface; B, a distribution technique is used to divide the control equation of the immersed boundary-lattice Boltzmann flux solver into a prediction step and a correction step; C, in the prediction step, the intermediate flow field velocity is solved by using the lattice Boltzmann flux solver; D, in the correction step, the intermediate flow field velocity is corrected by using the improved boundary condition forced immersed boundary method to obtain a new flow field velocity; E, if the simulation time is reached, the whole simulation process is ended, and if the simulation time is not reached, the step B is returned to. The flow-solid coupling method can meet the non-slip boundary condition, does not cause the non-physical flow line penetration phenomenon, and eliminates the complicated matrix solving process, so that a large amount of calculation cost can be saved, and the method is suitable for three-dimensional incompressible flow simulation of immersed objects.

The invention relates to a power support unit (100) for a movable flap (110), in particular for a vehicle flap, with at least one pivotally connected adjusting element (120), wherein the adjusting element (120) has a working chamber (130) filled with a fluid and at least one piston rod (140) which partially penetrates the working chamber (130) as well as a guide and sealing package (160) arranged at a first end (122) of the adjusting element (120) and sealing the adjusting element (120). According to the invention, the working chamber (130) is completely filled with an incompressible fluid and a spring chamber (180) is provided, which is sealed and separated from the working chamber (130) by means of a separating element (200) which is movable in the adjusting element (120), in which a spring element (190) is arranged to pressurize the separating element (200) in such a way that the piston rod (140) can be extended, wherein the spring element (190) is provided as a mechanical spring element and / or as a pressurized gas filling. The invention further relates to an adjustment device for a movable flap (110), in particular for a vehicle flap, with a power support unit (100) and a further adjustment element (330).

The application discloses a kind of method, equipment, medium and system for calculating local compressible flow in low-speed flow field, belong to the field of computational fluid dynamics, comprising the following steps: in the process of calculating local compressible flow in low-speed flow field, different algorithms are used to process by grid velocity determination;When the speed in the grid is less than the set value one, the incompressible pressure correction equation is solved;When the speed is between the set value one and the set value two, the compressible pressure correction equation is solved, and the interface density correction calculation result is calculated by linear interpolation method;When the grid speed is greater than the set value two, the compressible pressure correction equation is solved.The present application can obtain more accurate low-speed flow field and local compressible flow field, and is suitable for calculating local incompressible flow field.

The application discloses a flexible cover layer for inhibiting underwater bubble jet load and a manufacturing method thereof, and comprises a flexible cover layer, a rubber outer layer and a closed-cell foam sandwich layer; the rubber outer layer and the closed-cell foam sandwich layer are pasted to form the flexible cover layer; the other side of the closed-cell foam sandwich layer is pasted to a cabin wall or a side plate of an underwater vehicle; the rubber outer layer supports and protects the closed-cell foam sandwich layer, and prevents the closed-cell foam sandwich layer from being torn under the action of explosion impact due to the thin single foam wall; the manufacturing method comprises the following steps: obtaining material parameters through experiments, obtaining explosion load information through a scaled-down experiment; presetting the thickness of each layer, coupling numerical solutions of compressible fluid models and incompressible fluid models with a finite element structure model, performing finite element numerical calculation, optimizing the structure thickness according to the finite element calculation result, and manufacturing the flexible cover layer according to the thickness. The application has the advantages of better absorbing shock wave energy generated by underwater explosion and inhibiting and blocking the impact of high-speed bubble jet load.

An apparatus constrainable to a diver, including a buoyancy control system for a diver including: —a rigid means which identifies an operating zone; the operating zone being intended to receive a gas and an incompressible liquid; the zone being defined by a first chamber or by the sum of at least a first and a second chamber; —a first means for introducing the incompressible fluid into the operating zone; —a first means for introducing the gas into the operating zone; —a pressurised tank of the gas, the first means for introducing the gas being operatively interposed between the tank and the operating zone; —a means for evacuating a fluid from the operating zone, the fluid being the gas and / or the incompressible liquid.

The application provides a method for predicting the grouting slurry diffusion range of a coal seam floor area, comprising: obtaining a slurry water displacement model containing minefield stratum parameters and grouting borehole parameters of the coal seam floor area; obtaining a Brinkman equation for describing the incompressible fluid flow caused by reinforcing materials in a porous medium based on the Navier-Stokes equation and the Darcy law; wherein the Brinkman equation contains a viscosity term and a pressure gradient term; taking the grouting pressure, slurry density, dynamic viscosity, porous medium permeability, and porous medium porosity as the influencing factors of slurry diffusion, and obtaining various parameter combinations of each influencing factor and level; using the various parameter combinations, simulating the slurry diffusion process based on the slurry water displacement model by using the Brinkman equation, to obtain the optimal parameter combination and the corresponding slurry diffusion range. The method can scientifically and accurately predict the slurry diffusion range, and improve the consistency and reliability of the grouting treatment effect.

The present invention relates to a method for determining, at any point in a geographical area and at any time, the evolution in time and space of a concentration (Cp) of at least one pollutant emitted by a source (SE) and dispersed by the wind. In the present invention, the pollutants are considered to be transported by the wind, via the solution of an advection-diffusion equation, and the wind is characterized by Laplace flow (irrotational and incompressible flow), using a wind velocity potential model (WVPM). Furthermore, the present invention defines boundary conditions (BC) of the Stokes equations to account for complex obstacle geometries and non-uniform wind conditions within the wind velocity field model (WVPM). Figure 1 to be published

The present invention discloses a valve assembly comprising a seat ring, a valve plate assembly movable between a sealed position within the seat ring and an open position outside the seat ring. A fitting can pass through the valve plate, and / or a sensor assembly can extend through the fitting with a sensor mounted below the valve plate assembly. The sensor assembly provides enhanced monitoring capabilities by being positioned in the incompressible fluid column below the valve plate assembly, ensuring accurate sensing of relevant parameters. This configuration allows for efficient and reliable operation of the valve assembly, enhancing its performance and functionality in various applications.

The invention relates to the technical field of simulation experiments, in particular to a thermodynamic system simulation modeling method and system, electronic equipment and a storage medium, and the thermodynamic system simulation modeling method comprises the following steps: respectively establishing branch models for incompressible fluid and compressible fluid; establishing a node model based on the branch model; wherein nodes with the pressure of P in the node model are connected with m nodes or boundaries at the upstream through m branches, and are connected with n-m nodes or boundaries at the downstream through n-m branches; m and n are positive integers; calculating the pressure on each node in n nodes based on the node model; and calculating the flow on each branch based on the pressure on each node. According to the method, the simulation precision and the calculation efficiency of the thermodynamic system can be improved, and the equipment characteristics can be simulated more accurately, so that serious accidents and the like are analyzed and researched, the economic loss is avoided, and the usability is high.

The invention aims to provide a structure-keeping pressure correction projection numerical method for an incompressible Navier-Stokes equation, which is characterized in that a dynamic energy dissipation structure and an incompressible constraint structure of a continuous equation are kept on a discrete level by introducing nonlinear energy equivalent reconstruction and a grad-div stabilization mechanism on the basis of a rotary pressure correction projection framework. According to the method, the velocity field and the pressure field can be effectively decoupled in each time step, a nonlinear equation is converted into a plurality of constant coefficient linear sub-problems to be solved, and complete linearization and operator structure maintenance of the calculation process are achieved. According to the method, the physical consistency of flow simulation is kept, meanwhile, the numerical stability and the calculation efficiency are remarkably improved, the problems that in a traditional projection method, the time step length is limited, operators are difficult to assemble repeatedly, and energy deviation is accumulated are solved, and the method is suitable for stable numerical simulation of high-precision incompressible flow.

The invention discloses a method, equipment, medium and system for calculating local compressible flow in a low-speed flow field, and belongs to the field of fluid power calculation, and the method comprises the following steps: in the process of calculating the local compressible flow in the low-speed flow field, different algorithms are adopted for processing through grid speed judgment; when the speed in the grid is smaller than a first set value, an incompressible pressure correction equation is adopted for solving; when the speed is between a set value I and a set value II, solving by adopting a compressible pressure correction equation, and calculating an interface density correction calculation result through a linear interpolation method; and when the grid speed is greater than a set value 2, solving by adopting a compressible pressure correction equation. According to the method, the accurate low-speed flow field and the local compressible flow field can be obtained, and the method is suitable for calculating the local part in the incompressible flow field.

The invention discloses an improved semi-implicit thermal hydraulic multi-scale coupling method. The method comprises the following steps: establishing a system program model and a computational fluid mechanics model; steady-state flow is obtained according to the system program model, and pressure drop is obtained through a computational fluid mechanics model; iteratively adjusting the boundary pressure of the system program model to enable the local pressure drop to be equal to the obtained pressure drop, and updating the steady-state flow until a preset precision requirement is met; after steady-state initialization is completed, transient flow is obtained according to a system program model; transient pressure drop is obtained through a computational fluid mechanics model; and the boundary pressure of the system program model is iteratively adjusted, so that the transient local pressure drop is equal to the obtained transient pressure drop, and the transient flow is updated until the preset precision requirement is met. According to the invention, the number of transmission parameters at the coupling boundary is reduced, and the efficiency of pipeline incompressible flow semi-implicit thermal hydraulic multi-scale coupling is improved.

The invention provides an incompressible fluid elliptic partial differential equation wavelet transform convolutional neural network multi-network (WTCNN-MG) numerical solution method, and belongs to the field of incompressible fluid mechanics numerical calculation, and the method specifically comprises the steps: adaptively optimizing convolution-based smoothing, differential, limiting and continuation operations, and reducing the spectral radius of an iteration matrix; the WTCNN is integrated to carry out additional self-adaptive low-frequency smoothing error correction on the coarse grid hierarchy; and low-frequency and high-frequency characteristics are effectively extracted by using the multi-resolution characteristic of the wavelet, and rapid approximation of a low-frequency smoothing error is realized. The invention designs an integrally differentiable WTCNN-MG method, on the premise of ensuring the same precision as the MG method, the calculation efficiency is improved by nearly 90 times, and an efficient incompressible fluid elliptic partial differential equation numerical solution scheme is provided.