Numerical Calculation Method and System for Dynamic Process Gas-Heat Characteristics Analysis of Adjustable Turbine

Abstract

This invention relates to the field of turbine blade numerical analysis technology, and particularly to a numerical calculation method, system, device, and storage medium for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine. This method, by employing an overlapping mesh approach, avoids the shortcomings of traditional calculation methods, such as difficulty in maintaining mesh quality, poor stability of the dynamic simulation process, and low accuracy and reliability of the results. It achieves continuous calculation of the dynamic process of the adjustable turbine, rather than discrete calculation of a few state points during the change process. Compared to the large amount of repetitive work involved in "adjusting geometry, meshing, setting boundary conditions, and numerical calculation" resulting from traditional calculations at multiple hub points, this method requires only one preprocessing and unsteady numerical calculation, greatly reducing the workload. This method is simple, applicable to a wide range of blade adjustment motion functions, and can realize various types of blade geometric adjustment motions.

Description

Technical Field

[0001] This invention relates to the field of numerical analysis technology for turbine blades, specifically to a numerical calculation method, system, device, and storage medium for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine. Background Technology

[0002] Gas turbines are a crucial component of aero engines, and turbine blades are an essential part of gas turbine engines. To ensure high efficiency in gas turbine engines under varying environmental conditions, researchers are actively conducting numerical calculations to adjust engine efficiency by modifying the turbine blade angle of attack. To achieve complex control over gas flow, thrust, and other parameters of aero engines at different flight altitudes and speeds, the dynamic numerical calculation of turbine blade angle of attack and the analysis of its aero-thermal characteristics become extremely important.

[0003] During the variable mounting angle of turbine blades, the geometry of the computational domain undergoes significant changes, necessitating modifications to the shape and structure of the discrete mesh. Previous numerical simulations typically employed smoothing, layup, and reconstructed dynamic meshing methods. However, due to the substantial shearing motion between the blade's top and bottom surfaces and the upper and lower end walls of the cascade passage during variable mounting angles, dynamic meshing methods often struggle to maintain mesh quality in this dynamic simulation process. Negative volume can even occur, compromising the stability, accuracy, and reliability of the results. Overlapping meshing methods avoid these shortcomings in dynamic simulations. While currently used in dynamic processes such as rotor camber, airborne weapon launches, landing gear retraction and extension, and active anti-roll fin actuation in ships, the overlapping meshing method has not yet been applied to aero-engines, particularly variable geometry turbine blades, due to the high-temperature, high-pressure flow environment within the cascade passage. Numerical analysis of adjustable turbine blades with variable mounting angles still relies on discrete methods. Summary of the Invention

[0004] To address the issue that the overlapping mesh method is not currently applied to aero-engines, especially variable geometry turbine blades, due to the high-temperature and high-pressure flow environment within the blade passage, this invention provides a numerical calculation method for analyzing the dynamic process aero-thermal characteristics of an adjustable turbine.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] This invention provides a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine, comprising:

[0007] S1: Establish a blade virtual surface between the blade and the cascade channel fluid domain, divide the cascade channel fluid domain into the channel background fluid domain and the component fluid domain surrounding the blade, divide the channel background fluid domain mesh into the background mesh, and divide the component fluid domain mesh surrounding the blade into the component mesh.

[0008] S2: Initialize the computational domain composed of the background mesh and the component mesh, make the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law;

[0009] S3: Based on the angular velocity of the blade rotation in the current time step, in the computational domain after the motion law is given, control the component fluid domain surrounding the blade to rotate in the channel background fluid domain, and use the virtual surface as the starting surface of the data exchange interface between the background mesh and the component mesh overlapping part, update the data exchange between the background mesh and the component mesh overlapping part, and perform unsteady numerical iterative calculations at the current time step until convergence.

[0010] S4: Set the next time step as the current time step:

[0011] S5: Iterate through S3-S4 until the preset number of iterations is reached;

[0012] S6: By combining the unsteady numerical calculation results at each time step, the gas-thermal characteristics of the adjustable turbine in the dynamic process are obtained.

[0013] Furthermore, the background fluid domain of the channel is the area enclosed by the casing surface, hub surface, two periodic surfaces, inlet boundary surface, and outlet boundary surface.

[0014] Furthermore, the component fluid domain surrounding the blade refers to the fluid space formed outside the blade surface and within the blade virtual surface surrounding the blade.

[0015] Furthermore, the blade virtual face covers all surfaces of the blade, and the distance between the end face of the blade virtual face and the end face of the blade is 0.5% to 1.8% of the blade height; the distance between the four sides of the blade virtual face and the surrounding surfaces of the blade is 4% to 8% of the blade chord length.

[0016] Preferably, the overlapping portion of the background grid and the component grid has more than or equal to 4 overlapping grids, and the background grid and the component grid in the overlapping area are of the same size.

[0017] Furthermore, the specific method of S2 is as follows:

[0018] The computational domain consisting of the background mesh and the component mesh is initialized so that the background mesh and the component mesh overlap.

[0019] Before a blade motion begins, the time span T of a blade motion process is extended forward by time t1.

[0020] After one blade movement is completed, the time span T of one blade movement process is extended backward by time t2;

[0021] The total time is: t1 + T + t2;

[0022] When the current time t≤t1, the blade is stationary, then the blade's velocity is ν=f'(t)=0;

[0023] When t1 < the current time t ≤ (t1 + T), the blade motion law is f(t - t1), and the blade velocity is ν = f'(t - t1);

[0024] When (t1+T) < the current time t, the blade is stationary, then the blade's velocity is ν = f'(t) = 0;

[0025] The laws of motion are assigned to the initialized computational domain.

[0026] Furthermore, the forward extension time t1 is a time span T of 0.01 to 0.2 times of one blade movement process; the backward extension time t2 is a time span T of 0.2 to 1 times of one blade movement process.

[0027] A numerical calculation method system for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine, comprising:

[0028] Mesh generation module: Used to create a virtual surface for the blade between the blade and the cascade passage fluid domain, divide the cascade passage fluid domain into the passage background fluid domain and the component fluid domain surrounding the blade, and divide the passage background fluid domain mesh into the background mesh and the component fluid domain mesh surrounding the blade into the component mesh.

[0029] The blade motion law assignment module is used to initialize the computational domain composed of the background mesh and the component mesh, make the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law.

[0030] The unsteady numerical iterative calculation module at the current time step is used to control the component fluid domain surrounding the blade to rotate in the channel background fluid domain within the computational domain after the motion law is assigned, based on the angular velocity of the blade rotation in the current time step. It also uses a virtual surface as the starting surface for the data exchange interface between the background mesh and the component mesh, updates the data exchange between the background mesh and the component mesh, and performs unsteady numerical iterative calculation at the current time step until convergence.

[0031] Current time step setting module: Used to set the next time step as the current time step.

[0032] Iterative calculation module: used for iteratively calculating the unsteady values ​​of the next time step;

[0033] Gas-thermal characteristics acquisition module: used to integrate the unsteady numerical calculation results at each time step to obtain the gas-thermal characteristics of the adjustable turbine in the dynamic process.

[0034] A terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to perform the steps of the method described above.

[0035] A computer-readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements the steps of the method described above.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] This invention discloses a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine. The algorithm separates the blade passage fluid domain into a background fluid domain and a component fluid domain surrounding the blade. Based on the blade motion law, it controls the rotation of the component fluid domain within the background fluid domain. The meshes corresponding to the two fluid domains overlap in space and exchange data, enabling the editing of dynamic process gas-thermal characteristics analysis and numerical calculation of the dynamic process of the adjustable turbine. This method employs an overlapping mesh approach, avoiding the shortcomings of traditional calculation methods, such as difficulty in maintaining mesh quality, poor stability of the dynamic simulation calculation process, and low accuracy and reliability of the results. It achieves continuous calculation of the dynamic process of the adjustable turbine, rather than discrete calculation of a few state points during the change process. Compared to the large amount of repetitive work of "adjusting geometry, dividing mesh, setting boundary conditions, and numerical calculation" resulting from traditional calculations with multiple hub-and-spoke points, this method requires only one preprocessing and unsteady numerical calculation, greatly reducing the workload. This method is simple, applicable to a wide range of blade adjustment motion functions, and can realize various types of blade geometric adjustment motions.

[0038] The background fluid domain of the channel is defined as the area enclosed by the casing surface, hub surface, two periodic surfaces, inlet boundary surface, and outlet boundary surface. The component fluid domain surrounding the blade refers to the fluid space formed from outside the blade surface to the virtual surface surrounding the blade. This ensures the smooth application of the overlapping mesh method in aero-engines, especially variable geometry turbine blades, and guarantees the reliability and accuracy of numerical calculations.

[0039] The blade virtual surface covers all surfaces of the blade, and the distance between the end face of the virtual surface and the end face of the blade is 0.5% to 1.8% of the blade height; the distance between the four sides of the virtual surface and the surrounding surfaces of the blade is 4% to 8% of the blade chord length. This ensures that during the calculation, the fluid domain of the component surrounding the blade always has at least four layers of mesh overlapping with the background fluid domain of the channel, while controlling the number of meshes and reducing computational costs.

[0040] This invention also provides a numerical calculation method system for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine. This system establishes a virtual blade surface between the blade and the cascade passage fluid domain through a mesh generation module. The cascade passage fluid domain is divided into a passage background fluid domain and a component fluid domain surrounding the blade. The passage background fluid domain mesh is then divided into a background mesh, and the component fluid domain mesh surrounding the blade is divided into a component mesh. Through a blade motion law assignment module, the computational domain composed of the background mesh and the component mesh is initialized, causing the background mesh and component mesh to overlap, and the initialized computational domain is assigned the blade motion law. Through an unsteady numerical iteration calculation module for the current time step, the system calculates the blade rotation based on the current time step. Angular velocity, within the computational domain after assigning motion laws, controls the rotation of the component fluid domain surrounding the blades within the channel background fluid domain. A virtual surface serves as the starting surface for data exchange between the overlapping parts of the background and component meshes, updating the data exchange and performing unsteady numerical iterative calculations at the current time step until convergence. By setting up the current time step setting module and the iterative calculation module, the next time step is used as the current time step for iterative calculations. Finally, through the setting of the gas-thermal characteristic acquisition module, the gas-thermal characteristics of the adjustable turbine during its dynamic process are acquired. The system has a simple structure, is easy to operate, and provides accurate and reliable calculation results, offering a reliable basis for subsequent numerical calculation research on adjusting engine efficiency.

[0041] The present invention provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method described above. The device has a simple structure, low modification cost, and low resource consumption.

[0042] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the method described above. This storage medium is highly portable and versatile. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine according to the present invention.

[0044] Figure 2 This is a three-dimensional schematic diagram showing the relative positions of the background channel fluid domain and the component fluid domain surrounding the blades in the numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine according to the present invention.

[0045] Figure 3 This is a three-dimensional schematic diagram of the background channel fluid domain in the numerical calculation method for dynamic process gas-thermal characteristic analysis of an adjustable turbine according to the present invention.

[0046] Figure 4 This is a three-dimensional schematic diagram of the fluid domain surrounding the blades in a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine according to the present invention.

[0047] Figure 5 This is a schematic diagram of the radial section blade rotation in a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine according to the present invention.

[0048] Figure 6 This is a structural diagram of a numerical calculation system for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine according to the present invention.

[0049] Among them, 1-channel background fluid domain, 2-component fluid domain surrounding the blade, 3-casing surface, 4-hub surface, 5-period surface, 6-inlet boundary surface, 7-outlet boundary surface, 8-blade surface, 9-blade virtual surface, 10-blade end face, 11-end face of blade virtual surface, 12-surrounding surface of blade, 13-surrounding surface of blade virtual surface, 14-position of component fluid domain surrounding the blade and blade at the current time step, 15-position of component fluid domain surrounding the blade and blade after one time step. Detailed Implementation

[0050] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0052] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0053] See Figures 1 to 5 This invention discloses a numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine, comprising:

[0054] S1: A blade virtual surface 9 is established between the blade and the cascade passage fluid domain. The cascade passage fluid domain is divided into a passage background fluid domain 1 and a component fluid domain 2 surrounding the blade. The mesh of the passage background fluid domain 1 is divided into a background mesh, and the mesh of the component fluid domain 2 surrounding the blade is divided into a component mesh. The passage background fluid domain 1 is the area enclosed by the casing surface 3, the hub surface 4, the two periodic surfaces 5, the inlet boundary surface 6, and the outlet boundary surface 7. The component fluid domain 2 surrounding the blade refers to the fluid space formed from outside the blade surface 8 to inside the blade virtual surface 9 surrounding the blade. The blade virtual surface 9 encloses all surfaces of the blade, and the distance between the end face 11 of the blade virtual surface and the end face 10 of the blade is 0.5% to 1.8% of the blade height. The distance between the surrounding surfaces 14 of the blade virtual surface and the surrounding surfaces 12 of the blade is 4% to 8% of the blade chord length.

[0055] S2: Initialize the computational domain composed of the background mesh and the component mesh, making the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law, specifically:

[0056] Import the background fluid domain 1 and the component fluid domain 2 surrounding the blade into the solver. Designate background fluid domain 1 as the background mesh; designate component fluid domain 2 surrounding the blade as the component mesh. Set boundary conditions within the solver to initialize the computational domain composed of the background mesh and the component mesh. Set the time step and total time according to requirements, and assign the blade motion law to this initialized computational domain.

[0057] Before a blade movement begins, the time span T of a blade movement process is extended forward by a time t1; the forward extension time t1 is 0.01 to 0.2 times the time span T of a blade movement process.

[0058] After one blade movement is completed, the time span T of one blade movement process is extended backward by time t2; the backward extension time t2 is 0.2 to 1 time span T of one blade movement process;

[0059] The total time is: t1 + T + t2;

[0060] When the current time t≤t1, the blade is stationary, then the blade's velocity is ν=f'(t)=0;

[0061] When t1 < the current time t ≤ (t1 + T), the blade motion law is f(t - t1), and the blade velocity is ν = f'(t - t1);

[0062] When (t1+T) < the current time t, the blade is stationary, then the blade's velocity is ν = f'(t) = 0;

[0063] Using the solver's dynamic mesh function, select the Rigid Body type motion mode to apply the above motion laws to the blade and the fluid domain 2 of the components surrounding the blade;

[0064] Wherein, the overlapping mesh of the background mesh and the component mesh has more than or equal to 4 layers, and the background mesh and the component mesh in the overlapping area are of the same size; the total time usually covers one blade movement process.

[0065] S3: Based on the blade rotation angle in the current time step, in the computational domain after assigning motion laws, control the component fluid domain 2 surrounding the blade to rotate in the channel background fluid domain 1, and use the blade virtual surface 9 as the starting surface of the data exchange interface between the background mesh and the component mesh overlapping part, update the data exchange between the background mesh and the component mesh overlapping part, and perform unsteady numerical iterative calculations in the current time step until convergence.

[0066] S4: Set the next time step as the current time step:

[0067] S5: Iterate through S3-S4 until the preset number of iterations is reached;

[0068] S6: By combining the unsteady numerical calculation results at each time step, the gas-thermal characteristics of the adjustable turbine in the dynamic process are obtained.

[0069] Taking a turbine blade as an example:

[0070] A virtual surface 9 is established between the blade and the cascade passage fluid domain. The cascade passage fluid domain is divided into a passage background fluid domain 1 and a component fluid domain 2 surrounding the blade. The mesh of the passage background fluid domain 1 is divided into a background mesh, and the mesh of the component fluid domain 2 surrounding the blade is divided into a component mesh. The passage background fluid domain 1 refers to the entire fluid domain that does not contain any moving parts. This fluid domain is surrounded by the casing surface 3, the hub surface 4, two periodic surfaces 5, the inlet boundary surface 6, and the outlet boundary surface 7. The component fluid domain 2 around the blade refers to the computational domain grid of the fluid space formed outside the blade surface 8 and inside the blade virtual surface 9. The blade virtual surface 9 must enclose all surfaces 8 of the blade and not contact the blade surface 8. The end face 11 of the blade virtual surface is 0.5% to 1.8% of the blade height away from the blade end face 10. The surrounding surfaces 13 of the blade virtual surface are 4% to 8% of the blade chord length away from the surrounding surfaces 12 of the blade. This ensures that the component fluid domain 2 around the blade always has more than four layers of grids overlapping with the channel background fluid domain 1 during the calculation process, while controlling the number of grids and reducing the computational cost.

[0071] The computational domain mesh must satisfy the requirement that the number of mesh layers in the overlapping part of the component fluid domain 2 mesh around the blade and the channel background fluid domain 1 mesh is not less than four, and that the size of the background mesh and the component mesh are kept as consistent as possible in the overlapping area.

[0072] Import the channel background fluid domain 1 mesh and the flow calculation domain 2 mesh around the blade into the solver, and designate the flow calculation domain 1 mesh as the background mesh and the component fluid domain 2 mesh around the blade as the component mesh. In the solver, set the virtual surface 9 around the blade described in step 1 as the data exchange interface for overlapping mesh calculation.

[0073] Boundary conditions are set within the solver, the computational domain is initialized, and the time step and total time are defined. The total time typically covers the entire blade motion process, from start to finish, with an extension time t1 before the start. t1 is typically 0.01 to 0.2 motion cycles. Performing unsteady calculations at time t1 before blade motion yields the flow field before blade rotation. An extension time t2 is performed after the motion process ends, with t2 typically 0.1 to 1 motion cycle. Performing unsteady calculations at time t2 after blade motion yields the flow field after blade rotation.

[0074] In this example, the blade rotates around its actuation axis. The motion law of the blade, f(t), is a piecewise function, where t is the time of the blade's motion, and f(t) is the angle the blade rotates through as a function of time t. The blade rotates by an angle of 2A throughout the entire process, and the time span of the blade's rotation is T.

[0075] When the calculation time t≤t1, the blade does not rotate, f(t)=0, and the angular velocity of the blade rotation ν=f'(t)=0;

[0076] When the calculation time t1 < t ≤ (t1 + T), the blade rotates according to a continuously differentiable sine function law, and the specific expression of f(t) is:

[0077]

[0078] The specific calculation method for the angular velocity ν that drives the blade rotation is ν=f'(t), and the specific expression for ν is:

[0079]

[0080] When (t1+T)<t, the blade does not rotate, and the angular velocity of the blade rotation is set to ν=f'(t)=0.

[0081] Use the solver's dynamic mesh function to select the Rigid Body type motion mode to apply the above motion to the component mesh fluid domain and rotating blades.

[0082] Based on existing blade motion patterns and the current time step, calculate the displacement that should occur at the current time step and control the fluid domain of the components around the blade and the movement of the blade itself: For example... Figure 5 As shown, the blade rotates from position 14 (the fluid domain surrounding the blade at the current time step) to position 15 (the fluid domain surrounding the blade at the next time step). Then, the data exchange method between the background mesh and the component mesh is refreshed, and unsteady numerical iterative calculations are performed at the current time step until convergence.

[0083] The next time step is taken as the current time step, and the unsteady values ​​of each time step are iteratively calculated until the preset number of iterations is reached. The gas-thermal characteristics of the adjustable turbine in the dynamic process are obtained by combining the calculation results of the unsteady values ​​of each time step.

[0084] See Figure 6 A numerical calculation method system for dynamic process gas-thermal characteristic analysis of an adjustable turbine.

[0085] Mesh generation module: used to create a blade virtual surface 9 between the blade and the cascade channel fluid domain, divide the cascade channel fluid domain into channel background fluid domain 1 and component fluid domain 2 surrounding the blade, and divide the channel background fluid domain 1 mesh into background mesh, and divide the component fluid domain 2 mesh surrounding the blade into component mesh.

[0086] The blade motion law assignment module is used to initialize the computational domain composed of the background mesh and the component mesh, make the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law.

[0087] The unsteady numerical iterative calculation module at the current time step is used to control the component fluid domain 2 surrounding the blade to rotate in the channel background fluid domain 1 in the computational domain after the motion law is given, based on the angular velocity of the blade rotation in the current time step. It also uses the virtual surface as the starting surface of the data exchange interface between the background mesh and the component mesh, updates the data exchange between the background mesh and the component mesh, and performs unsteady numerical iterative calculation at the current time step until convergence.

[0088] Current time step setting module: Used to set the next time step as the current time step.

[0089] Iterative calculation module: used for iteratively calculating the unsteady values ​​of the next time step;

[0090] Gas-thermal characteristics acquisition module: used to integrate the unsteady numerical calculation results at each time step to obtain the gas-thermal characteristics of the adjustable turbine in the dynamic process.

[0091] This invention provides a terminal device comprising: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps in the various method embodiments described above. Alternatively, when the processor executes the computer program, it implements the functions of each module / unit in the various device embodiments described above.

[0092] The computer program can be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention.

[0093] The terminal device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0094] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0095] The memory can be used to store the computer program and / or module. The processor implements various functions of the terminal device by running or executing the computer program and / or module stored in the memory and calling the data stored in the memory.

[0096] If the modules / units integrated into the terminal device are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0097] The above description is merely a preferred embodiment of the present invention and is not intended to limit the technical solution of the present invention in any way. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can be modified and replaced in several simple ways, and these modifications and replacements are all within the scope of protection covered by the claims.

Claims

1. A numerical calculation method for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine, characterized in that, include: S1: Establish a blade virtual surface between the blade and the cascade channel fluid domain, divide the cascade channel fluid domain into the channel background fluid domain and the component fluid domain surrounding the blade, divide the channel background fluid domain mesh into the background mesh, and divide the component fluid domain mesh surrounding the blade into the component mesh. S2: Initialize the computational domain composed of the background mesh and the component mesh, make the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law; S3: Based on the angular velocity of the blade rotation in the current time step, in the computational domain after the motion law is given, control the component fluid domain surrounding the blade to rotate in the channel background fluid domain, and use the virtual surface as the starting surface of the data exchange interface between the background mesh and the component mesh overlapping part, update the data exchange between the background mesh and the component mesh overlapping part, and perform unsteady numerical iterative calculations at the current time step until convergence. S4: Set the next time step as the current time step: S5: Iterate through S3-S4 until the preset number of iterations is reached; S6: By combining the unsteady numerical calculation results at each time step, the gas-thermal characteristics of the adjustable turbine in the dynamic process are obtained.

2. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 1, characterized in that, The background fluid domain of the channel is the area enclosed by the casing surface, hub surface, two periodic surfaces, inlet boundary surface, and outlet boundary surface.

3. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 1, characterized in that, The fluid domain surrounding the blade refers to the fluid space formed outside the blade surface and within the blade's virtual surface surrounding the blade.

4. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 3, characterized in that, The blade virtual face covers all surfaces of the blade, and the distance between the end face of the blade virtual face and the end face of the blade is 0.5% to 1.8% of the blade height; the distance between the four sides of the blade virtual face and the surrounding surfaces of the blade is 4% to 8% of the blade chord length.

5. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 1, characterized in that, The overlapping area of ​​the background grid and the component grid has more than 4 overlapping grids, and the background grid and the component grid in the overlapping area are the same size.

6. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 1, characterized in that, The specific method for S2 is as follows: The computational domain consisting of the background mesh and the component mesh is initialized so that the background mesh and the component mesh overlap. Before a blade motion begins, the time span T of a blade motion process is extended forward by time t1. After one blade movement is completed, the time span T of one blade movement process is extended backward by time t2; The total time is: t1 + T + t2; When the current time t≤t1, the blade is stationary, then the blade's velocity is ν=f'(t)=0; When t1 < the current time t ≤ (t1 + T), the blade motion law is f(t - t1), and the blade velocity is ν = f'(t - t1); When (t1+T) < the current time t, the blade is stationary, then the blade's velocity is ν = f'(t) = 0; The laws of motion are assigned to the initialized computational domain.

7. The numerical calculation method for dynamic process gas-thermal characteristic analysis of the adjustable turbine according to claim 6, characterized in that, The forward extension time t1 is the time span T of 0.01 to 0.2 times of one blade movement process; the backward extension time t2 is the time span T of 0.2 to 1 times of one blade movement process.

8. A numerical calculation method system for analyzing the dynamic process gas-thermal characteristics of an adjustable turbine, characterized in that, include: Mesh generation module: Used to create a virtual surface for the blade between the blade and the cascade passage fluid domain, divide the cascade passage fluid domain into the passage background fluid domain and the component fluid domain surrounding the blade, and divide the passage background fluid domain mesh into the background mesh and the component fluid domain mesh surrounding the blade into the component mesh. The blade motion law assignment module is used to initialize the computational domain composed of the background mesh and the component mesh, make the background mesh and the component mesh overlap, and assign the initialized computational domain to the blade motion law. The unsteady numerical iterative calculation module at the current time step is used to control the component fluid domain surrounding the blade to rotate in the channel background fluid domain within the computational domain after the motion law is assigned, based on the angular velocity of the blade rotation in the current time step. It also uses a virtual surface as the starting surface for the data exchange interface between the background mesh and the component mesh, updates the data exchange between the background mesh and the component mesh, and performs unsteady numerical iterative calculation at the current time step until convergence. Current time step setting module: Used to set the next time step as the current time step. Iterative calculation module: used for iteratively calculating the unsteady values ​​of the next time step; Gas-thermal characteristics acquisition module: used to integrate the unsteady numerical calculation results at each time step to obtain the gas-thermal characteristics of the adjustable turbine in the dynamic process.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-7.

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