Analytical method and apparatus for evaluating flow stability of a compressor under thermal shock distortion

Abstract

The present disclosure relates to the technical field of compressor analysis, and particularly provides a method and device for evaluating the flow stability of a compressor under thermal shock distortion, the method comprising: constructing Euler equations of a compressor to be evaluated; obtaining small disturbance equations of the compressor based on small disturbance assumption and the Euler equations, and solving the small disturbance equations based on flow field data in a thermal shock process to obtain small disturbance solutions of the compressor, the small disturbance equations being determined based on an assumption that disturbance amplitude variation of small disturbance is consistent with thermal shock distortion disturbance variation or an assumption that thermal shock distortion disturbance is periodic disturbance; determining boundary conditions of blades in the compressor based on a disk model and parallel compressor theory, and determining a system stability characteristic equation of the compressor according to the boundary conditions and the small disturbance solutions; and determining a flow stability evaluation result of the compressor according to a solving result of the system stability characteristic equation. The present disclosure reduces the difficulty of evaluating the flow stability of the compressor under thermal shock distortion.

Description

Technical Field

[0001] This disclosure relates to the field of compressor analysis technology, and in particular to a method and apparatus for evaluating the flow stability of compressors under thermal shock distortion. Background Technology

[0002] During short takeoff and landing of aircraft, the reverse thrust exhaust gas from the engine or the exhaust gas from weapon launches can be drawn into the compressor, causing thermal shock distortion at the compressor inlet. This can prevent the compressor from operating at its design point, leading to a decrease in compressor stability. Therefore, compressor flow stability assessment becomes increasingly important during the compressor design phase.

[0003] In related technologies, in order to study the flow stability of a compressor, the stability index parameters of the compressor can usually be obtained through experiments, or the stability of the compressor can be evaluated by constructing a compressor model.

[0004] However, the compressor flow stability assessment schemes provided in related technologies not only require a large amount of experimental data and have high experimental costs, but also, this compressor flow stability assessment scheme based on stable layer index parameters or compressor models is usually applicable to compressor flow stability assessment under uniform air intake conditions, and is not applicable to compressor flow stability assessment under thermal shock distortion conditions. Summary of the Invention

[0005] This disclosure is made in view of the above-mentioned problems. This disclosure provides a method and apparatus for evaluating the flow stability of compressors under thermal shock distortion, improving the accuracy of flow stability evaluation results for high-load compressors under thermal shock distortion conditions.

[0006] According to one aspect of this disclosure, an analytical method for evaluating compressor flow stability under thermal shock distortion is provided, comprising:

[0007] Construct the Euler equations for the compressor to be evaluated;

[0008] Based on the small perturbation assumption and the Euler equation, the small perturbation equation of the compressor is obtained, and the small perturbation equation is solved based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor. The small perturbation equation is either the first small perturbation equation or the second small perturbation equation. The first small perturbation equation is determined based on the assumption that the change in the perturbation amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet. The second small perturbation equation is determined based on the assumption that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation.

[0009] Based on the excitation disk model and parallel compressor theory, the boundary conditions of the blades inside the compressor are determined, and based on the boundary conditions and the small disturbance solution, the system stability characteristic equation of the compressor under thermal shock distortion is determined.

[0010] Based on the solution results of the system stability characteristic equation, the flow stability assessment results of the compressor are determined.

[0011] According to another aspect of this disclosure, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the above-described method for evaluating and analyzing the flow stability of a compressor under thermal shock distortion.

[0012] According to another aspect of this disclosure, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the above-described analytical method for evaluating compressor flow stability under thermal shock distortion.

[0013] The method and apparatus for evaluating the flow stability of a compressor under thermal shock distortion disclosed herein can construct the Euler equations for the compressor based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, or based on the assumption that the amplitude change of the small disturbance is consistent with the change of the thermal shock distortion disturbance at the compressor inlet. Based on the small disturbance assumption and the Euler equations for the compressor, the small disturbance equation considering thermal shock distortion is obtained. Furthermore, the small disturbance equation is solved based on the flow field data during the thermal shock process to obtain the small disturbance solution considering thermal shock distortion. Finally, based on the small disturbance solution and the solution results of the system stability characteristic equation of the compressor under thermal shock distortion constructed by the boundary conditions of the compressor blades, the stability of the compressor is analyzed. This realizes the stability analysis of the compressor under thermal shock distortion scenarios. Moreover, the compressor stability analysis based on the two assumptions does not require a large amount of flow field data during the thermal shock process, nor does it require the construction of a physical model, thus reducing the difficulty of evaluating and analyzing the flow stability of the compressor under thermal shock distortion scenarios.

[0014] It should be understood that both the foregoing general description and the following detailed description are exemplary and intended to provide further illustration of the claimed technology. Attached Figure Description

[0015] The above and other objects, features, and advantages of this disclosure will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0016] Figure 1 This is a flowchart illustrating an analytical method for evaluating compressor flow stability under thermal shock distortion according to an embodiment of this disclosure.

[0017] Figure 2 This is a block diagram illustrating a compressor flow stability assessment and analysis apparatus under thermal shock distortion according to an embodiment of the present disclosure.

[0018] Figure 3 This is a schematic diagram illustrating a computer program product according to an embodiment of the present disclosure.

[0019] Figure 4 This is a hardware block diagram illustrating an electronic device according to an embodiment of the present disclosure. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this disclosure more apparent, exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments of this disclosure. It should be understood that this disclosure is not limited to the exemplary embodiments described herein.

[0021] In related technologies, in order to evaluate the flow stability of a compressor, the stability index parameters of the compressor, such as the D factor, dimensionless diffusion length, consistency, aspect ratio, etc., can be determined experimentally, and the compressor can be designed based on these stability index parameters; or, a compressor model can be constructed using experimental data to evaluate the compressor stability and guide the compressor design.

[0022] However, the compressor flow stability assessment scheme based on stability index parameters and compressor models provided in related technologies not only requires the manufacture of related compressor components, but also the acquisition and processing of a large amount of experimental data, resulting in high experimental costs and long cycles. At the same time, this compressor flow stability assessment scheme based on stability index parameters and compressor models is usually applicable to compressor flow stability assessment under uniform air intake conditions, but not applicable to compressor flow stability assessment under thermal shock distortion conditions.

[0023] To address the aforementioned issues, this disclosure provides an analytical scheme for evaluating compressor flow stability under thermal shock distortion, such as... Figure 1 As shown, Figure 1 A flowchart illustrating an exemplary embodiment of this disclosure provides a method for evaluating the flow stability of a compressor under thermal shock distortion. This method can be applied to a terminal device, such as a computer, laptop, or tablet computer. Figure 1 As shown, the method in this embodiment of the disclosure may include:

[0024] Step S101: Construct the Euler equations for the compressor to be evaluated;

[0025] Step S102: Based on the small perturbation assumption and Euler's equations, the small perturbation equations of the compressor are obtained, and the small perturbation equations are solved based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor.

[0026] The small perturbation equation is either a first small perturbation equation or a second small perturbation equation. The first small perturbation equation is determined based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet. The second small perturbation equation is determined based on the assumption that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation.

[0027] Step S103: Based on the excitation disk model and parallel compressor theory, determine the boundary conditions of the blades inside the compressor, and determine the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and small disturbance solutions.

[0028] Step S104: Determine the flow stability assessment result of the compressor based on the solution result of the system stability characteristic equation.

[0029] In summary, the analytical method for evaluating compressor flow stability under thermal shock distortion provided in this disclosure can construct the Euler equations for the compressor based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, or based on the assumption that the change in the amplitude of the small disturbance is consistent with the change in the thermal shock distortion disturbance at the compressor inlet. Based on the small disturbance assumption and the Euler equations for the compressor, a small disturbance equation considering thermal shock distortion is obtained. Furthermore, the small disturbance equation is solved based on the flow field data during the thermal shock process to obtain a small disturbance solution considering thermal shock distortion. Finally, based on the small disturbance solution and the solution results of the system stability characteristic equation of the compressor under thermal shock distortion constructed from the boundary conditions of the compressor blades, the stability of the compressor is analyzed. This method achieves compressor stability analysis under thermal shock distortion scenarios. Moreover, the compressor stability analysis based on these two assumptions does not require a large amount of flow field data during the thermal shock process, nor does it require the construction of a physical model, thus reducing the difficulty of evaluating compressor flow stability under thermal shock distortion scenarios.

[0030] The following are Figure 1 The specific implementation methods of each step in the illustrated embodiment are described in detail below:

[0031] In step S101, the terminal device constructs the Euler equations for the compressor to be evaluated.

[0032] In this embodiment of the disclosure, in order to determine the control equations of the compressor under thermal shock distortion, it can be assumed that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, so that the compressor stability analysis can be performed using the Euler equations of the compressor constructed by referring to the harmonic balance method; or, based on the assumption that the change in the amplitude of the small disturbance is consistent with the change in the thermal shock distortion disturbance at the compressor inlet, the compressor stability analysis can be performed using the traditional Euler equations.

[0033] In one alternative implementation, based on the assumption that the change in the amplitude of a small disturbance is consistent with the change in the thermal shock distortion disturbance at the compressor inlet, the terminal equipment can determine that the Euler equation of the compressor to be evaluated is the first Euler equation in the conservation form:

[0034]

[0035] In one alternative implementation, assuming the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, even small disturbances will be affected by this, resulting in a first-order disturbance growth rate. Therefore, the terminal equipment can construct a second Euler equation in a conserved form for the compressor to be evaluated, based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, and the first Euler equation in a conserved form. This second Euler equation in a conserved form is:

[0036]

[0037] In formulas 1 and 2, Q = (Q1 Q2 … Q 2n+1 ) T F = (F1 F2 … F 2n+1 ) T G = (G1 G2 …G 2n+1 ) T , ρ is the fluid density, v is the circumferential fluid velocity, w is the axial fluid velocity, p is the fluid pressure, θ is the circumferential coordinate in the cylindrical coordinate system, r and z are the radial and axial coordinates in the cylindrical coordinate system, respectively, e is the internal energy, h is the enthalpy, E is the time spectrum matrix, t is the t-th time point among the 2n+1 time points selected in the periodic thermal shock distortion perturbation, and τ is the virtual time; where n is the number of series formed by the combination of sine and cosine functions after Fourier transforming the periodic thermal shock distortion perturbation.

[0038] The time spectrum matrix is ​​based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance. Using the harmonic balance method, it is obtained by expanding the flow field parameters at multiple time points selected in the periodic thermal shock distortion disturbance in Fourier form, determining the inverse matrix of the non-Fourier coefficient part matrix, and the product of the derivative matrix of the non-Fourier coefficient part matrix with respect to time. The multiple time points can be 2n+1 time points.

[0039] In step S102, the terminal device obtains the small perturbation equation of the compressor based on the small perturbation assumption and the Euler equation, and solves the small perturbation equation based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor.

[0040] In this embodiment of the disclosure, the flow field data during the thermal shock process is obtained by simulating the working process of the compressor using a software model. The small perturbation equation of the compressor is determined based on the non-conservative Euler equation corresponding to the conservative Euler equation. The non-conservative Euler equation includes the non-conservative first Euler equation or the non-conservative second Euler equation.

[0041] The non-conservative form of the first Euler equation is:

[0042]

[0043] In formula 3, Let be the average circumferential fluid velocity, and w be the average axial fluid velocity. The average fluid density γ is the mean of the radial coordinates, and γ is the specific heat ratio.

[0044] It should be noted that in the non-conservative form of the first Euler equation, The mass continuity equation is... and The momentum equation is... The equation for the speed of sound is equivalent to the energy equation under isentropic conditions.

[0045] Drawing upon the conservation form of the second Euler equation, the non-conservation form of the second Euler equation is obtained as follows:

[0046]

[0047] In formula 4, E iLet be the i-th row of the time spectrum matrix, where ρ is the fluid density matrix at multiple time points selected in the periodic thermal shock distortion perturbation, v is the circumferential fluid velocity matrix at multiple time points selected in the periodic thermal shock distortion perturbation, w is the axial fluid velocity matrix at multiple time points selected in the periodic thermal shock distortion perturbation, and p is the fluid pressure matrix at multiple time points selected in the periodic thermal shock distortion perturbation.

[0048] It should be noted that in the non-conservative form of the first Euler equation, The mass continuity equation is... and The momentum equation is... This is the energy equation.

[0049] It should be noted that, in the embodiments of this disclosure, the small perturbation equation is either a first small perturbation equation or a second small perturbation equation. The first small perturbation equation is determined based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet. The second small perturbation equation is determined based on the assumption that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation.

[0050] In one optional implementation, the Euler equation is a non-conservative form of the first Euler equation. The process by which the terminal device obtains the small perturbation equation of the compressor based on the small perturbation assumption and the Euler equation may include: if the average quantity of the flow field parameters satisfies the non-conservative form of the first Euler equation, updating the flow field parameters in the non-conservative form of the first Euler equation based on the average quantity of the flow field parameters to obtain the updated first equation; further, based on the principle of linearization of the flow field parameters, determining the difference between the non-conservative form of the first Euler equation and the updated first equation as the first small perturbation equation of the compressor, and based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet, determining the small perturbation quantity of the flow field parameters in the first small perturbation equation as:

[0051]

[0052] In Formula 5, k q The rate of change of the amplitude of the small disturbance is the same as the rate of change of the thermal shock distortion disturbance at the compressor inlet; wherein, the rate of change of the thermal shock distortion disturbance at the compressor inlet is determined based on the flow field information obtained after modeling the compressor under thermal shock conditions.

[0053] The first small perturbation equation is:

[0054]

[0055] In formula 6, ρt ′ represents the fluid density perturbation at time point t in the thermal shock distortion perturbation, v t ′ represents the circumferential fluid velocity disturbance at time point t, w t ′ represents the circumferential fluid velocity disturbance at time point t, p t ′ represents the fluid pressure disturbance at time point t. Let be the average circumferential fluid velocity at time point t. Let be the average axial fluid velocity at time point t. Let be the average fluid density at time point t. Based on the assumption that the change in the amplitude of the small disturbance is consistent with the change in the thermal shock distortion disturbance at the compressor inlet, the flow field parameters in the first small disturbance equation can be updated. This updated first small disturbance equation can characterize the change in small disturbances caused by thermal shock through the change in the thermal shock distortion disturbance at the compressor inlet, without increasing the complexity of the small disturbance equation, thus improving the efficiency of compressor stability assessment under thermal shock distortion conditions.

[0056] It should be noted that, in the embodiments of this disclosure, the principle of linearization of flow field parameters refers to the fact that flow field parameters can be characterized as the sum of the average quantity of flow field parameters and the small perturbation quantity of flow field parameters.

[0057] In one optional implementation, the process by which the terminal device derives the small perturbation equation of the compressor based on the small perturbation assumption and the Euler equation may include: assuming that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation; based on the small perturbation assumption, determining that in the non-conservative form of the Euler equation, the flow field parameters are the average quantities of the flow field parameters, and the sum of the small perturbation quantities of the flow field parameters, to obtain the flow field parameter characterization equation; then, based on the flow field parameter characterization equation and the non-conservative form of the Euler equation, obtaining the small perturbation equation of the compressor. Wherein, the flow field parameters include fluid density, circumferential fluid velocity, axial fluid velocity, and fluid pressure, and the average quantities of the flow field parameters are:

[0058]

[0059] In Formula 7, Let ω be the average value of the flow field parameters, n be multiple time points selected during the periodic thermal shock distortion disturbance, and ω be the average value of the flow field parameters. t Let N be the periodic frequency of the disturbance, and N be the truncated Fourier series.

[0060] The small disturbance of the flow field parameters is:

[0061]

[0062] In Equation 8, q′ is the small disturbance quantity of the flow field parameter, ω is the complex characteristic frequency, τ is time, and m is the circumferential wavenumber of the disturbance quantity;

[0063] The equation characterizing the flow field parameters is:

[0064]

[0065] In Equation 9, q represents the flow field parameter. Based on the small perturbation assumption, the flow field parameter characterization equation can be determined by assuming that the thermal shock distortion is a periodic perturbation, using the average quantity equation and the small perturbation quantity equation of the flow field parameter. Based on the flow field parameter characterization equation, as well as the non-conservative form of the Euler equation under the thermal shock inlet distortion of the compressor, a more accurate small perturbation equation can be determined to characterize the small perturbation of the compressor under the condition that the thermal shock inlet distortion is a periodic distortion.

[0066] Understandably, when q is the fluid density, Equation 9 is... Similarly, when q is the fluid velocity and fluid density, the form of Equation 9 is similar to that when q is the fluid density, and this disclosure will not elaborate further.

[0067] In one optional implementation, the Euler equation is a non-conservative form of the second Euler equation. The process of obtaining the small perturbation equation of the compressor based on the flow field parameter characterization equation and the non-conservative form of the Euler equation may include: determining the non-conservative form of the second Euler equation based on the conservative form of the second Euler equation of the compressor to be evaluated; and, if it is determined that the average quantity of the flow field parameters satisfies the non-conservative form of the second Euler equation, updating the flow field parameters in the non-conservative form of the second Euler equation based on the average quantity of the flow field parameters to obtain the updated second equation; then, according to the... The flow field parameter characterization equation is determined by the difference between the non-conservative form of the second Euler equation and the updated Euler equation, which is used as the second small perturbation equation for the compressor. The conservative form of the second Euler equation includes a term containing the time spectrum matrix. This time spectrum matrix is ​​obtained by assuming that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation, and by using the harmonic balance method to determine the first derivative matrix of the perturbation amplitude with respect to time under thermal shock distortion. Furthermore, among the multiple time points selected in the periodic thermal shock distortion perturbation, the non-conservative form of the second small perturbation equation at time point t is:

[0068]

[0069] In Formula 10, E iLet be the i-th row of the time spectrum matrix, where ρ′ is the fluid density perturbation matrix selected at multiple time points in the periodic thermal shock distortion perturbation, v′ is the circumferential fluid velocity perturbation matrix selected at multiple time points in the periodic thermal shock distortion perturbation, w′ is the axial fluid velocity perturbation matrix selected at multiple time points in the periodic thermal shock distortion perturbation, and p′ is the fluid pressure perturbation matrix selected at multiple time points in the periodic thermal shock distortion perturbation; the time spectrum matrix consists of 2n+1 rows, E i This is the t-th row in the 2n+1 rows. By coupling the flow field parameter matrices at multiple time points selected in the periodic thermal shock distortion disturbance, we can obtain small perturbation equations that can accurately characterize the small perturbation conditions during the thermal shock distortion process.

[0070] It should be noted that, in the embodiments of this disclosure, when the terminal device determines the first small perturbation equation or the second small perturbation equation, based on the parallel compressor assumption, it is assumed that the circumferential flow field parameters are still average within a small range (mainly referring to the range of a single blade channel). Therefore, the circumferential non-uniformity can be neglected, and after neglecting the higher-order small quantities, the small perturbation equation of the compressor can be obtained. The small perturbation equation is the small perturbation equation of a single channel.

[0071] The process of the terminal equipment constructing the Euler equations of the compressor is realized in response to the Euler equations construction operation of the compressor; similarly, the process of the terminal equipment constructing the flow field parameter characterization equations within the compressor is realized in response to the flow field parameter characterization equations construction operation within the compressor.

[0072] In one optional implementation, the process by which the terminal device solves the small perturbation equation based on flow field data during the thermal shock process to obtain the small perturbation solution of the compressor may include: performing Helmholtz decomposition on the small perturbation equation to obtain the pressure perturbation equation in the irrotational field; further, solving the pressure perturbation equation based on the flow field data during the thermal shock process to obtain the pressure perturbation solution; then, substituting the pressure perturbation solution into the small perturbation equation to obtain the density perturbation solution and velocity perturbation solution in the irrotational field, wherein the velocity perturbation solution includes the circumferential velocity perturbation solution and the axial velocity perturbation solution; finally, determining the pressure perturbation solution, the density perturbation solution, the circumferential velocity perturbation solution, and the axial velocity perturbation solution as the small perturbation solution of the compressor. Solving the small perturbation equation based on flow field data during the thermal shock process can yield a small perturbation solution considering thermal shock distortion, thereby facilitating an accurate assessment of the compressor's stability under thermal shock distortion conditions.

[0073] It should be noted that, in the embodiments of this disclosure, the density perturbation solution and the velocity perturbation solution in the divergence-free field and the zero velocity field can also be solved separately. It can be found that the form of their solution is consistent with the homogeneous ordinary differential equation of the perturbation solution in the irrotational field. Therefore, the form of the solution can be merged into the density perturbation solution and the velocity perturbation solution. Since the pressure perturbation solution in the divergence-free field and the zero velocity field is 0, the final pressure perturbation solution usually includes the pressure perturbation solution in the irrotational field.

[0074] It is understood that, in the embodiments of this disclosure, when the terminal device solves the small perturbation equation based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor, the small perturbation equation used can be either the first small perturbation equation or the second small perturbation equation, and this embodiment of the disclosure does not limit it in this regard.

[0075] In one optional implementation, when the compressor's small perturbation solution is determined using the first small perturbation equation, the small perturbation solution includes a first pressure perturbation solution, a first density perturbation solution, a first circumferential velocity perturbation solution, and a first axial velocity perturbation solution. The process by which the terminal equipment performs Helmholtz decomposition on the small perturbation equation to obtain the pressure perturbation equation within the irrotational field includes: determining the circumferential perturbation velocity and the axial perturbation velocity of the fluid within the irrotational field based on the velocity potential; then, substituting the circumferential and axial perturbation velocities of the fluid within the irrotational field into the momentum equation in the first small perturbation equation to calculate the divergence; and then substituting the divergence solution into the continuity and energy equations for elimination to obtain the first pressure perturbation equation within the irrotational field.

[0076] Wherein, the circumferential disturbance velocity of the fluid in the irrotational field is The axial disturbance velocity of the fluid in the irrotational field is It represents the velocity potential.

[0077] The first pressure disturbance equation is:

[0078]

[0079] The process by which the terminal equipment solves the pressure disturbance equation based on flow field data during the thermal shock process to obtain the pressure disturbance solution can include: solving the first pressure disturbance equation based on the flow field data at time point t in the thermal shock distortion disturbance to obtain the first pressure disturbance solution. This method can obtain the pressure disturbance solution using flow field data at any time point in the thermal shock distortion disturbance, reducing the data processing complexity of determining the pressure disturbance solution under the assumption that the change in disturbance amplitude of a small disturbance is consistent with the change in thermal shock distortion disturbance at the compressor inlet, and improving the efficiency of compressor stability analysis. The first pressure disturbance solution is:

[0080]

[0081] The first density perturbation solution determined by the terminal device is:

[0082]

[0083] The solution for the first circumferential velocity perturbation is:

[0084]

[0085] The solution to the first axial velocity disturbance is:

[0086]

[0087] In formula 12, P 1 To determine the amplitude of the uploaded pressure wave, P 2 The amplitude of the downward pressure wave is given by the value of ...

[0088]

[0089] In Formula 16,

[0090]

[0091] It should be noted that in formulas 12 to 15, α 1 and α 2 Correlation with the uplink pressure wave and downlink pressure wave, respectively.

[0092] In formulas 13 to 15, D is the amplitude of the first small disturbance, V is the amplitude of the second small disturbance, W = (MW)V, and as well as, And (FMD), (SMD), (FMV), (SMV), (FMW), and (SMW) are constants related to the flow field data.

[0093] in,

[0094] In one optional implementation, when the compressor's small perturbation solution is determined using the second small perturbation equation, the small perturbation solution includes a second pressure perturbation solution, a second density perturbation solution, a second circumferential velocity perturbation solution, and a second axial velocity perturbation solution. The process by which the terminal equipment performs Helmholtz decomposition on the small perturbation equation to obtain the pressure perturbation equation within the irrotational field includes: determining the circumferential perturbation velocity and the axial perturbation velocity of the fluid within the irrotational field based on the velocity potential; then, substituting the circumferential and axial perturbation velocities of the fluid within the irrotational field into the momentum equation in the second small perturbation equation to calculate the divergence; and then substituting the divergence solution into the continuity and energy equations for elimination to obtain the second pressure perturbation equation within the irrotational field.

[0095] Similarly, the circumferential perturbation velocity of the fluid in an irrotational field is The axial disturbance velocity of the fluid in the irrotational field is

[0096] The second pressure disturbance equation is:

[0097]

[0098] The process by which the terminal equipment solves the pressure disturbance equation based on flow field data during the thermal shock process to obtain the pressure disturbance solution can include: solving the second pressure disturbance equation based on flow field data at multiple time points during the thermal shock process to obtain the second pressure disturbance solution. This can be achieved by obtaining the pressure disturbance solution from the flow field data at multiple time points during the thermal shock distortion disturbance. In the compressor stability analysis based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, the compressor stability analysis can be performed without a large amount of experimental data, reducing the difficulty and complexity of compressor stability analysis. The second pressure disturbance solution is:

[0099]

[0100] The second density perturbation solution determined by the terminal device is:

[0101]

[0102] The solution for the second circumferential velocity perturbation is:

[0103]

[0104] The solution to the second axial velocity disturbance is:

[0105]

[0106] In formulas 17 to 21, P 1 To upload the amplitude matrix of the pressure wave, P 2Let be the amplitude matrix of the transmitted pressure wave, D be the amplitude matrix of the first small disturbance, V be the amplitude matrix of the second small disturbance, and W = (MW)V, and .

[0107]

[0108] In formula 22,

[0109] in,

[0110] It should be noted that in formulas 19 to 21, α 1 and α 2 Correlation with the uplink pressure wave and downlink pressure wave, respectively.

[0111] Meanwhile, in Equations 18 to 22, FMD, SMD, FMV, SMV, FMW, and SMW are constant matrices related to the flow field data, where FMD satisfies the first equation, which is:

[0112] (FMD)(FMDC1)+(FMDC2)(FMD)+(FMDC3)=0; (Formula 23)

[0113] In formula 23, FMDC1=(Λiα) 1 ), as well as,

[0114] Understandably, the terminal device obtains the constant matrix of FMD by solving the first equation.

[0115] SMD satisfies the second equation, which is:

[0116] (SMD)(SMDC1)+(SMDC2)(SMD)+(SMDC3)=0; (Formula 24)

[0117] In formula 24, SMDC1=(Λiα) 2 ), as well as,

[0118] Understandably, the terminal device obtains the constant matrix of SMD by solving the second equation.

[0119] FMV satisfies a third-party process, wherein the third-party process is:

[0120] (FMV)(FMVC1)+(FMVC2)(FMV)+(FMVC3)=0; (Formula 25)

[0121] In formula 25, FMVC1=(Λiα) 1 ), as well as,

[0122] It is understandable that the terminal device obtains the constant matrix of FMV by solving a third-party program.

[0123] It should be noted that, for SMV, this is achieved by using α in the third-party process. 1 Replace with α 2 By solving this problem, we can obtain the constant matrix of SMV.

[0124] FMW satisfies the fourth equation, where the fourth equation is:

[0125] (FMW)(FMWC1)+(FMWC2)(FMW)+(FMWC3)=0; (Formula 26)

[0126] In formula 26, FMWC1=(Λiα) 1 ), as well as,

[0127] It should be noted that, for SMW, by using α in the fourth equation 1 Replace with α 2 By solving this problem, we can obtain the constant matrix of SMW.

[0128] In step S103, the terminal device can determine the boundary conditions of the blades inside the compressor based on the excitation disk model and parallel compressor theory, and determine the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and the small disturbance solution.

[0129] In this embodiment of the disclosure, the induced draft disk model can assume that the compressor blades are induced draft disks without thickness, and adopt the parallel compressor theory in the circumferential direction to determine the flow characteristics of the airflow on the front and rear sides of the compressor blades, including mass conservation, enthalpy conservation, total pressure lumped loss condition, Kutta condition, and other flow characteristics. Among them, other flow characteristics can be determined based on actual conditions, and this embodiment of the disclosure does not limit them.

[0130] In one optional implementation, the process by which the terminal device determines the boundary conditions of the compressor blades based on the induced disc model and parallel compressor theory may include: determining the flow characteristics of the airflow on the front and rear sides of the compressor blades based on the induced disc model and parallel compressor theory; further, constructing the flow characteristic equations of the airflow on the front and rear sides of the blades to obtain the boundary conditions of the compressor blades; wherein, the flow characteristics include mass conservation, enthalpy conservation, total pressure lumped loss condition, and Kutta condition; the flow characteristics of the airflow on both sides of the compressor blades may be determined based on the induced disc model and parallel compressor theory, and the flow characteristic equations of the blades may be constructed based on the flow characteristics as boundary conditions, so as to construct a more accurate system stability characteristic equation for the compressor under thermal shock inlet distortion.

[0131] The mass conservation equation constructed under the condition of mass conservation is as follows:

[0132] (ρw′+wρ′) - =(ρw′+wρ′) + ;(Formula 27)

[0133] The enthalpy conservation equation constructed under the condition of enthalpy conservation is as follows:

[0134]

[0135] In Equation 28, Ω is the compressor speed, and according to the right-hand rule, the direction is from the inlet to the outlet.

[0136] The Kuta condition equations constructed under the Kuta conditions are as follows:

[0137] (wv′-(v-Ωr)w′) + =0; (Formula 29)

[0138] The process of constructing the total pressure lumped loss condition equation under the total pressure lumped loss condition can include:

[0139] Define the total pressure loss coefficient ζ as:

[0140] ζ=p t - -p t + ;(Formula 30)

[0141] In formula 30, Where R is the average radius of the compressor.

[0142] Furthermore, assuming that the relative total pressure loss coefficient ζ is equal to the tangent of the relative intake airflow angle β1, then:

[0143] ζ=ζ(tanβ1); (Formula 31)

[0144] In formula 31, The small perturbation relative to the tangent of the intake airflow angle is

[0145] Furthermore, since there is a response delay between the instantaneous total pressure loss coefficient ζ′ disturbance and the intake velocity disturbance, it is assumed that they satisfy a first-order delay equation, then:

[0146]

[0147] Next, substituting Equation 30 into Equation 32 and combining it with Equation 31, we can obtain the initial total pressure lumped loss condition equation as follows:

[0148]

[0149] Furthermore, by rearranging the initial total pressure lumped loss condition equation, we can obtain the total pressure lumped loss condition equation as follows:

[0150]

[0151] In one optional implementation, the flow characteristics include mass conservation, enthalpy conservation, total pressure lumped loss condition, and Kutta condition. The process by which the terminal equipment determines the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and the small perturbation solution may include:

[0152] Substituting the small perturbation solution into the boundary conditions and adding inlet and outlet parameter conditions, the system stability characteristic equation of the compressor under thermal shock distortion is obtained. Wherein, if the small perturbation solution is the solution result of the first small perturbation equation, the system stability characteristic equation is:

[0153]

[0154] In formula 35, 0 I 0 0[0] 1×4n For the imported downlink pressure wave matrix, 0 0 I 0[0] 1×4n For the imported downlink density wave matrix, 0 0 0 I[0] 1×4n For the imported downlink velocity wave matrix, [0] 1×4nI000 represents the pressure wave matrix at the outlet. A1 is the pressure amplitude matrix at the leading edge of the blade under mass conservation conditions. B1 is the density amplitude matrix at the leading edge of the blade under mass conservation conditions. C1 is the velocity amplitude matrix at the leading edge of the blade under mass conservation conditions. H1 is the pressure amplitude matrix at the trailing edge of the blade under mass conservation conditions. F1 is the density amplitude matrix at the trailing edge of the blade under mass conservation conditions. G1 is the velocity amplitude matrix at the trailing edge of the blade under mass conservation conditions. A2 is the pressure amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. B2 is the density amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. C2 is the velocity amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. H2 is the pressure amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. F2 is the density amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. G2 is the velocity amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. The following matrix represents the pressure amplitude matrix: A3 is the pressure amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; B3 is the density amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; C3 is the velocity amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; H3 is the pressure amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; F3 is the density amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; G3 is the velocity amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; A4 is the pressure amplitude matrix at the leading edge of the blade under Kutta conditions; B4 is the density amplitude matrix at the leading edge of the blade under Kutta conditions; C4 is the velocity amplitude matrix at the leading edge of the blade under Kutta conditions; H4 is the pressure amplitude matrix at the trailing edge of the blade under Kutta conditions; F4 is the density amplitude matrix at the trailing edge of the blade under Kutta conditions; G4 is the velocity amplitude matrix at the trailing edge of the blade under Kutta conditions; P 1 To determine the amplitude of the uploaded pressure wave, P 2 The amplitude of the transmitted pressure wave is represented by D, the amplitude of the first small disturbance is represented by V, - indicates the front side of the blade, and + indicates the rear side of the blade.

[0155] Wherein, when the solution to the small perturbation is the result of solving the second small perturbation equation, the system stability characteristic equation is:

[0156]

[0157] In formula 36, ​​P 1 To upload the amplitude matrix of the pressure wave, P 2 Let be the amplitude matrix of the transmitted pressure wave, D be the amplitude matrix of the first small disturbance, and V be the amplitude matrix of the second small disturbance.

[0158] In step S104, the terminal device determines the flow stability assessment result of the compressor based on the solution result of the system stability characteristic equation.

[0159] In one optional implementation, the process by which the terminal device determines the flow stability assessment result of the compressor based on the solution result of the system stability characteristic equation may include: simplifying the system stability characteristic equation, which belongs to a closed equation, into an updated system stability characteristic equation; then, solving the updated system stability characteristic equation based on the singular value decomposition method to obtain the value of the complex characteristic frequency; further, if the imaginary part of the complex characteristic frequency is less than zero, then the compressor system is determined to be unstable; or, if the imaginary part of the complex characteristic frequency is greater than zero, then the compressor system is determined to be stable.

[0160] The updated system stability characteristic equation is as follows:

[0161] X(ω)δ=0;(Formula 37)

[0162] In Equation 37, X(ω) is the coefficient matrix, i.e., the matrix δ is the unknown in Equation 18, where, if the system stability characteristic equation is the equation in Equation 35, then δ is a matrix. If the system stability characteristic equation is the equation in Formula 36, ​​then δ is a matrix.

[0163] It should be noted that in this embodiment of the disclosure, the updated system stability characteristic equation is a homogeneous set of equations. The necessary and sufficient condition for the existence of small disturbances in the compressor system is det(X(ω))=0. The complex characteristic frequency is obtained by traversing through the singular value decomposition method. The imaginary part of the complex characteristic frequency can characterize whether the flow state of the compressor is stable.

[0164] An exemplary embodiment of this disclosure provides a compressor flow stability assessment and analysis device under thermal shock distortion, which can be a server or a chip applied to a server. Figure 2 A schematic block diagram of the functional modules of a compressor flow stability assessment and analysis apparatus under thermal shock distortion according to an exemplary embodiment of the present disclosure is shown. Figure 2 As shown, the compressor flow stability assessment and analysis device 200 under thermal shock distortion includes:

[0165] Module 201 is configured to construct the Euler equations for the compressor to be evaluated;

[0166] The acquisition module 202 is configured to obtain the small perturbation equation of the compressor based on the small perturbation assumption and the Euler equation, and solve the small perturbation equation based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor. The small perturbation equation is either a first small perturbation equation or a second small perturbation equation. The first small perturbation equation is determined based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet. The second small perturbation equation is determined based on the assumption that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation.

[0167] The first determining module 203 is configured to determine the boundary conditions of the blades inside the compressor based on the excitation disk model and parallel compressor theory, and to determine the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and the small disturbance solution.

[0168] The second determining module 204 is configured to determine the flow stability assessment result of the compressor based on the solution result of the system stability characteristic equation.

[0169] Optionally, the acquisition module 202 is configured as follows:

[0170] If the average quantity of the flow field parameters satisfies the first Euler equation in non-conservative form, the flow field parameters in the first Euler equation in non-conservative form are updated based on the average quantity of the flow field parameters to obtain the updated first equation.

[0171] Based on the principle of linearization of flow field parameters, the difference between the non-conservative form of the first Euler equation and the updated first equation is determined as the first small perturbation equation of the compressor. Based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet, the small perturbation quantity of the flow field parameters in the first small perturbation equation is determined as follows:

[0172] q′=∑q′(z)(1+k q τ)e iωτ+imθ ;

[0173] Where, k q The first small disturbance is defined as the rate of change of its amplitude, which is the same as the rate of change of the thermal shock distortion disturbance at the compressor inlet.

[0174]

[0175] Where, ρ t ′ represents the fluid density perturbation at time point t in the thermal shock distortion perturbation, v t ′ represents the circumferential fluid velocity disturbance at time point t, w t′ represents the circumferential fluid velocity disturbance at time point t, p t ′ represents the fluid pressure disturbance at time point t. Let be the average circumferential fluid velocity at time point t. Let be the average axial fluid velocity at time point t. Let be the average fluid density at time point t.

[0176] Optionally, the acquisition module 202 is configured as follows:

[0177] Assuming the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, based on the small disturbance assumption, the flow field parameters in the non-conservative form of the Euler equations are determined to be the average quantities of the flow field parameters, and the sum of the small disturbance quantities of the flow field parameters, thus obtaining the flow field parameter characterization equation. The flow field parameters include fluid density, circumferential fluid velocity, axial fluid velocity, and fluid pressure. The average quantities of the flow field parameters are:

[0178]

[0179] in, Let ω be the average value of the flow field parameters, n be multiple time points selected during the periodic thermal shock distortion disturbance, and ω be the average value of the flow field parameters. t Let N be the periodic frequency of the disturbance, and N be the truncated Fourier series.

[0180] The small disturbance of the flow field parameters is:

[0181]

[0182] Where q′ is the small disturbance quantity of the flow field parameter, ω is the complex characteristic frequency, τ is time, and m is the circumferential wavenumber of the disturbance quantity;

[0183] The equation characterizing the flow field parameters is:

[0184]

[0185] Where q is the flow field parameter;

[0186] Based on the flow field parameter characterization equation and the non-conservative form of the Euler equation, the small perturbation equation of the compressor is obtained.

[0187] Optionally, the acquisition module 202 is configured as follows:

[0188] Based on the conserved form of the second Euler equation with respect to the compressor to be evaluated, the non-conserved form of the second Euler equation is determined. The conserved form of the second Euler equation includes a term containing the time spectrum matrix. The time spectrum matrix is ​​obtained by expanding the flow field parameters at multiple time points selected in the periodic thermal shock distortion disturbance in Fourier form, based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, and by using the harmonic balance method. The inverse matrix of the non-Fourier coefficient part matrix is ​​then determined, along with the product of the derivative matrix of the non-Fourier coefficient part matrix with respect to time.

[0189] If the average quantity of the flow field parameters satisfies the second Euler equation in non-conservative form, the flow field parameters in the second Euler equation in non-conservative form are updated based on the average quantity of the flow field parameters to obtain the updated second equation.

[0190] Based on the flow field parameter characterization equation, the difference between the non-conservative form of the second Euler equation and the updated second equation is determined as the second small perturbation equation of the compressor. The second small perturbation equation is as follows:

[0191]

[0192] Where, ρ t Let v' be the fluid density perturbation at time point t among multiple time points selected in the periodic thermal shock distortion perturbation. t ′ represents the circumferential fluid velocity disturbance at time point t, w t ′ represents the circumferential fluid velocity disturbance at time point t, p t ′ represents the fluid pressure disturbance at time point t. Let be the average circumferential fluid velocity at time point t. Let be the average axial fluid velocity at time point t. E represents the average fluid density at time point t. i Let be the i-th row of the time spectrum matrix, where ρ′ is the fluid density perturbation matrix at multiple time points selected in the periodic thermal shock distortion perturbation, v′ is the circumferential fluid velocity perturbation matrix at multiple time points selected in the periodic thermal shock distortion perturbation, w′ is the axial fluid velocity perturbation matrix at multiple time points selected in the periodic thermal shock distortion perturbation, and p′ is the fluid pressure perturbation matrix at multiple time points selected in the periodic thermal shock distortion perturbation.

[0193] Optionally, the acquisition module 202 is configured as follows:

[0194] The small perturbation equation is decomposed by Helmholz to obtain the pressure perturbation equation in the irrotational field;

[0195] Based on the flow field data during the thermal shock process, the pressure disturbance equation is solved to obtain the pressure disturbance solution;

[0196] Substituting the pressure perturbation solution into the small perturbation equation, density perturbation solutions and velocity perturbation solutions are obtained in the irrotational field, the divergence-free field, and the zero velocity field, wherein the velocity perturbation solution includes circumferential velocity perturbation solution and axial velocity perturbation solution;

[0197] The pressure perturbation solution, the density perturbation solution, the circumferential velocity perturbation solution, and the axial velocity perturbation solution are determined as the small perturbation solutions of the compressor.

[0198] Optionally, the first determining module 203 is configured as follows:

[0199] Based on the induced disk model and parallel compressor theory, the flow characteristics of the airflow on the front and rear sides of the blades in the compressor are determined. The flow characteristics include mass conservation, enthalpy conservation, total pressure lumped loss condition and Kutta condition.

[0200] The flow characteristic equations of the airflow on the front and rear sides of the blades are constructed to obtain the boundary conditions of the blades inside the compressor.

[0201] Optionally, the small perturbation solution is the solution result of the first small perturbation equation, and the first determining module 203 is configured as follows:

[0202] Substituting the small perturbation solution into the boundary conditions and adding inlet and outlet parameter conditions, the system stability characteristic equation of the compressor under thermal shock distortion is obtained. The system stability characteristic equation is:

[0203]

[0204] Among them, 0 I 0 0[0] 1×4n For the imported downlink pressure wave matrix, 0 0 I 0[0] 1×4n For the imported downlink density wave matrix, 0 0 0 I[0] 1×4n For the imported downlink velocity wave matrix, [0] 1×4nI000 represents the pressure wave matrix at the outlet. A1 is the pressure amplitude matrix at the leading edge of the blade under mass conservation conditions. B1 is the density amplitude matrix at the leading edge of the blade under mass conservation conditions. C1 is the velocity amplitude matrix at the leading edge of the blade under mass conservation conditions. H1 is the pressure amplitude matrix at the trailing edge of the blade under mass conservation conditions. F1 is the density amplitude matrix at the trailing edge of the blade under mass conservation conditions. G1 is the velocity amplitude matrix at the trailing edge of the blade under mass conservation conditions. A2 is the pressure amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. B2 is the density amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. C2 is the velocity amplitude matrix at the leading edge of the blade under enthalpy conservation conditions. H2 is the pressure amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. F2 is the density amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. G2 is the velocity amplitude matrix at the trailing edge of the blade under enthalpy conservation conditions. The following matrix represents the pressure amplitude matrix: A3 is the pressure amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; B3 is the density amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; C3 is the velocity amplitude matrix at the leading edge of the blade under total pressure and lumped loss conditions; H3 is the pressure amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; F3 is the density amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; G3 is the velocity amplitude matrix at the trailing edge of the blade under total pressure and lumped loss conditions; A4 is the pressure amplitude matrix at the leading edge of the blade under Kutta conditions; B4 is the density amplitude matrix at the leading edge of the blade under Kutta conditions; C4 is the velocity amplitude matrix at the leading edge of the blade under Kutta conditions; H4 is the pressure amplitude matrix at the trailing edge of the blade under Kutta conditions; F4 is the density amplitude matrix at the trailing edge of the blade under Kutta conditions; G4 is the velocity amplitude matrix at the trailing edge of the blade under Kutta conditions; P 1 To determine the amplitude of the uploaded pressure wave, P 2 The amplitude of the transmitted pressure wave is represented by D, the amplitude of the first small disturbance is represented by V, - indicates the front side of the blade, and + indicates the rear side of the blade.

[0205] Optionally, the small perturbation solution is the solution result of the second small perturbation equation, and the first determining module 203 is configured to:

[0206] Substituting the small perturbation solution into the boundary conditions and adding inlet and outlet parameter conditions, the system stability characteristic equation of the compressor under thermal shock distortion is obtained. The system stability characteristic equation is:

[0207]

[0208] Among them, P 1 Let P be the amplitude matrix of the first small perturbation. 2 Let be the second smallest perturbation amplitude matrix, D be the third smallest perturbation amplitude matrix, and V be the fourth smallest perturbation amplitude matrix.

[0209] Exemplary embodiments of this disclosure also provide an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor. The memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to cause the electronic device to perform a method according to an embodiment of this disclosure.

[0210] Exemplary embodiments of this disclosure also provide a non-transitory computer-readable storage medium storing a computer program, wherein the computer program, when executed by a computer's processor, is used to cause the computer to perform a method according to embodiments of this disclosure.

[0211] like Figure 3 As shown, an exemplary embodiment of this disclosure also provides a computer program product 300, including a computer program 301, wherein the computer program, when executed by a computer's processor, is used to cause the computer to perform a method according to an embodiment of this disclosure.

[0212] refer to Figure 4 The present invention describes a structural block diagram of an electronic device 400 that can serve as a terminal device of the present disclosure, which is an example of a hardware device that can be applied to various aspects of the present disclosure. The electronic device is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0213] like Figure 4 As shown, the electronic device 400 includes a computing unit 401, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 402 or a computer program loaded from a storage unit 408 into a random access memory (RAM) 403. The RAM 403 may also store various programs and data required for the operation of the electronic device 400. The computing unit 401, ROM 402, and RAM 403 are interconnected via a bus 404. An input / output (I / O) interface 405 is also connected to the bus 404.

[0214] Multiple components in electronic device 400 are connected to I / O interface 405, including: input unit 406, output unit 407, storage unit 408, and communication unit 409. Input unit 406 can be any type of device capable of inputting information to electronic device 400. Input unit 406 can receive input digital or character information and generate key signal inputs related to user settings and / or function control of electronic device. Output unit 407 can be any type of device capable of presenting information and may include, but is not limited to, a display, speaker, video / audio output terminal, vibrator, and / or printer. Storage unit 408 may include, but is not limited to, disks and optical discs. Communication unit 409 allows electronic device 400 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks, and may include, but is not limited to, modems, network cards, infrared communication devices, wireless communication transceivers, and / or chipsets, such as Bluetooth™ devices, WiFi devices, WiMax devices, cellular communication devices, and / or the like.

[0215] The computing unit 401 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 401 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 401 performs the various methods and processes described above. For example, in some embodiments, the methods of the exemplary embodiments of this disclosure can be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 408. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device 400 via ROM 402 and / or communication unit 409. In some embodiments, the computing unit 401 can be configured to perform the methods of the exemplary embodiments of this disclosure by any other suitable means (e.g., by means of firmware).

[0216] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0217] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0218] As used in this disclosure, the terms "machine-readable medium" and "computer-readable medium" refer to any computer program product, device, and / or apparatus (e.g., disk, optical disk, memory, programmable logic device (PLD)) for providing machine instructions and / or data to a programmable processor, including machine-readable media that receive machine instructions as machine-readable signals. The term "machine-readable signal" refers to any signal for providing machine instructions and / or data to a programmable processor.

[0219] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0220] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as a data server), or computing systems that include middleware components (e.g., an application server), or computing systems that include frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with embodiments of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., a communication network). Examples of communication networks include local area networks (LANs), wide area networks (WANs), and the Internet.

[0221] Computer systems can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. Client-server relationships are created by computer programs running on the respective computers and having a client-server relationship with each other.

[0222] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this disclosure are performed, in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a terminal, a user equipment, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center integrating one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video disc (DVD); or it can be a semiconductor medium, such as a solid-state drive (SSD).

[0223] Although this disclosure has been described in conjunction with specific features and embodiments, it will be apparent that various modifications and combinations can be made therein without departing from the spirit and scope of this disclosure. Accordingly, this specification and drawings are merely exemplary illustrations of the disclosure as defined by the appended claims and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this disclosure. It is obvious that those skilled in the art can make various alterations and modifications to this disclosure without departing from its spirit and scope. Thus, this disclosure is also intended to include any such modifications and modifications that fall within the scope of the claims of this disclosure and their equivalents.

Claims

1. A method for evaluating the flow stability of a compressor under thermal shock distortion, characterized in that, include: Construct the Euler equations for the compressor to be evaluated; Based on the small perturbation assumption and the Euler equation, the small perturbation equation of the compressor is obtained, and the small perturbation equation is solved based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor. The small perturbation equation is either the first small perturbation equation or the second small perturbation equation. The first small perturbation equation is determined based on the assumption that the change in the perturbation amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet. The second small perturbation equation is determined based on the assumption that the thermal shock distortion perturbation at the compressor inlet is a periodic perturbation. Based on the excitation disk model and parallel compressor theory, the boundary conditions of the blades inside the compressor are determined, and based on the boundary conditions and the small disturbance solution, the system stability characteristic equation of the compressor under thermal shock distortion is determined. Based on the solution results of the system stability characteristic equation, the flow stability assessment results of the compressor are determined; The small perturbation equations for the compressor, derived based on the small perturbation assumption and the Euler equations, include: Given that the average quantity of flow field parameters satisfies the first Euler equation in non-conservative form, the flow field parameters in the first Euler equation in non-conservative form are updated based on the average quantity of flow field parameters to obtain the updated first equation. Based on the principle of linearization of flow field parameters, the difference between the non-conservative form of the first Euler equation and the updated first equation is determined as the first small perturbation equation of the compressor. Based on the assumption that the change in the amplitude of the small perturbation is consistent with the change in the thermal shock distortion perturbation at the compressor inlet, the small perturbation quantity of the flow field parameters in the first small perturbation equation is determined as follows: ； in, This is the rate of change of the amplitude of the small disturbance, which is the same as the rate of change of the thermal shock distortion disturbance at the compressor inlet. For virtual time, For complex characteristic frequencies, The circumferential wavenumber of the disturbance quantity These are the circumferential coordinates in a cylindrical coordinate system. The first small perturbation equation is: ； in, Let be the fluid density perturbation at time point t in the thermal shock distortion perturbation. For the circumferential fluid velocity disturbance at time point t, For the axial fluid velocity disturbance at time point t, Let be the fluid pressure disturbance at time point t. Let be the average circumferential fluid velocity at time point t. Let be the average axial fluid velocity at time point t. Let be the mean fluid density at time point t. The mean of the radial coordinates. These are radial coordinates in a cylindrical coordinate system. Specific heat ratio.

2. The analytical method for evaluating compressor flow stability under thermal shock distortion as described in claim 1, characterized in that, The small perturbation equations for the compressor, derived based on the small perturbation assumption and the Euler equations, include: Assuming the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, based on the small disturbance assumption, the flow field parameters in the non-conservative form of the Euler equations are determined to be the average quantities of the flow field parameters, and the sum of the small disturbance quantities of the flow field parameters, thus obtaining the flow field parameter characterization equation. The flow field parameters include fluid density, circumferential fluid velocity, axial fluid velocity, and fluid pressure. The average quantities of the flow field parameters are: ； in, These are the average values ​​of the flow field parameters. These are multiple time points selected during periodic thermal shock distortion perturbations. Let be the periodic frequency of the disturbance. For the truncated Fourier series, t is the t-th time point among the 2n+1 time points selected in the periodic thermal shock distortion disturbance; The small disturbance of the flow field parameters is: ； in, For small disturbances in the flow field parameters, For complex characteristic frequencies, For virtual time, The circumferential wavenumber of the disturbance; The equation characterizing the flow field parameters is: ； in, These are the flow field parameters; Based on the flow field parameter characterization equation and the non-conservative form of the Euler equation, the small perturbation equation of the compressor is obtained.

3. The method for evaluating and analyzing the flow stability of a compressor under thermal shock distortion as described in claim 2, characterized in that, The small perturbation equations of the compressor, derived from the flow field parameter characterization equations and the non-conservative form of the Euler equations, include: Based on the conserved form of the second Euler equation with respect to the compressor to be evaluated, the non-conserved form of the second Euler equation is determined. The conserved form of the second Euler equation includes a term containing the time spectrum matrix. The time spectrum matrix is ​​obtained by expanding the flow field parameters at multiple time points selected in the periodic thermal shock distortion disturbance in Fourier form, based on the assumption that the thermal shock distortion disturbance at the compressor inlet is a periodic disturbance, and by using the harmonic balance method. The inverse matrix of the non-Fourier coefficient part matrix is ​​then determined, along with the product of the derivative matrix of the non-Fourier coefficient part matrix with respect to time. If the average quantity of the flow field parameters satisfies the non-conservative form of the second Euler equation, the flow field parameters in the non-conservative form of the second Euler equation are updated based on the average quantity of the flow field parameters to obtain the updated second equation. Based on the flow field parameter characterization equation, the difference between the non-conservative form of the second Euler equation and the updated second equation is determined as the second small perturbation equation of the compressor. The second small perturbation equation is as follows: ； in, This refers to the fluid density perturbation at time point t, selected from multiple time points in a periodic thermal shock distortion perturbation. For the circumferential fluid velocity disturbance at time point t, For the axial fluid velocity disturbance at time point t, Let be the fluid pressure disturbance at time point t. Let be the average circumferential fluid velocity at time point t. Let be the average axial fluid velocity at time point t. Let be the mean fluid density at time point t. For the i-th row of the time spectrum matrix, This represents the fluid density perturbation matrix selected at multiple time points during periodic thermal shock distortion perturbation. This represents the circumferential fluid velocity perturbation matrix selected at multiple time points during periodic thermal shock distortion perturbation. This represents the axial fluid velocity perturbation matrix selected at multiple time points during periodic thermal shock distortion perturbation. This represents the fluid pressure perturbation matrix selected at multiple time points during periodic thermal shock distortion perturbation. The mean of the radial coordinates. These are the circumferential coordinates in a cylindrical coordinate system. These are the axial coordinates in a cylindrical coordinate system. For virtual time, Specific heat ratio.

4. The analytical method for evaluating compressor flow stability under thermal shock distortion as described in claim 1, characterized in that, The method of solving the small perturbation equation based on the flow field data during the thermal shock process to obtain the small perturbation solution of the compressor includes: The small perturbation equation is decomposed by Helmholz to obtain the pressure perturbation equation in the irrotational field; Based on the flow field data during the thermal shock process, the pressure disturbance equation is solved to obtain the pressure disturbance solution; Substituting the pressure perturbation solution into the small perturbation equation, density perturbation solutions and velocity perturbation solutions are obtained in the irrotational field, the divergence-free field, and the zero velocity field, wherein the velocity perturbation solution includes circumferential velocity perturbation solution and axial velocity perturbation solution; The pressure perturbation solution, the density perturbation solution, the circumferential velocity perturbation solution, and the axial velocity perturbation solution are determined as the small perturbation solutions of the compressor.

5. The analytical method for evaluating compressor flow stability under thermal shock distortion as described in claim 1, characterized in that, The boundary conditions for the blades within the compressor, based on the excitation disk model and parallel compressor theory, are determined, including: Based on the induced disk model and parallel compressor theory, the flow characteristics of the airflow on the front and rear sides of the blades in the compressor are determined. The flow characteristics include mass conservation, enthalpy conservation, total pressure lumped loss condition and Kutta condition. The flow characteristic equations of the airflow on the front and rear sides of the blades are constructed to obtain the boundary conditions of the blades inside the compressor.

6. The method for evaluating and analyzing the flow stability of a compressor under thermal shock distortion as described in claim 5, characterized in that, The small perturbation solution is the solution result of the first small perturbation equation. The step of determining the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and the small perturbation solution includes: Substituting the small perturbation solution into the boundary conditions and adding inlet and outlet parameter conditions, the system stability characteristic equation of the compressor under thermal shock distortion is obtained. The system stability characteristic equation is: in, For the imported down-transmission pressure wave matrix, For the imported downlink density wave matrix, For the imported downlink velocity wave matrix, Upload the pressure wave matrix to the outlet. This is the pressure amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the density amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the velocity amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the pressure amplitude matrix behind the blade under the condition of mass conservation. This is the density amplitude matrix on the trailing side of the blade under the condition of mass conservation. This is the velocity amplitude matrix on the trailing side of the blade under the condition of mass conservation. This is the pressure amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the density amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the velocity amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the pressure amplitude matrix behind the blade under the condition of enthalpy conservation. This is the density amplitude matrix on the trailing side of the blade under the condition of enthalpy conservation. This is the velocity amplitude matrix on the trailing side of the blade under the condition of enthalpy conservation. This is the pressure amplitude matrix at the leading edge of the blade under total pressure lumped-down conditions. This is the density amplitude matrix on the leading side of the blade under total pressure lumped total loss conditions. This is the velocity amplitude matrix at the leading edge of the blade under total pressure lumped loss conditions. This is the pressure amplitude matrix behind the blade under total pressure lumped-down conditions. This is the density amplitude matrix on the trailing side of the blade under total pressure lumped loss conditions. This is the velocity amplitude matrix at the trailing edge of the blade under total pressure lumped loss conditions. This is the pressure amplitude matrix on the leading side of the blade under Kutta conditions. This is the density amplitude matrix on the leading side of the blade under Kuta conditions. This is the velocity amplitude matrix of the leading edge of the blade under Kutta conditions. This is the pressure amplitude matrix behind the blade under Kutta conditions. This is the density amplitude matrix on the trailing side of the blade under Kuta conditions. This is the velocity amplitude matrix on the trailing side of the blade under Kutta conditions. To upload the amplitude of the pressure wave, The amplitude of the transmitted pressure wave. This is the amplitude of the first small disturbance. The value represents the second smallest disturbance, with - indicating the front side of the blade and + indicating the rear side.

7. The method for evaluating and analyzing the flow stability of a compressor under thermal shock distortion as described in claim 5, characterized in that, The small perturbation solution is the solution result of the second small perturbation equation. The step of determining the system stability characteristic equation of the compressor under thermal shock distortion based on the boundary conditions and the small perturbation solution includes: Substituting the small perturbation solution into the boundary conditions and adding inlet and outlet parameter conditions, the system stability characteristic equation of the compressor under thermal shock distortion is obtained. The system stability characteristic equation is: ； in, For the imported down-transmission pressure wave matrix, For the imported downlink density wave matrix, For the imported downlink velocity wave matrix, Upload the pressure wave matrix to the outlet. This is the pressure amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the density amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the velocity amplitude matrix on the leading side of the blade under the condition of mass conservation. This is the pressure amplitude matrix behind the blade under the condition of mass conservation. This is the density amplitude matrix on the trailing side of the blade under the condition of mass conservation. This is the velocity amplitude matrix on the trailing side of the blade under the condition of mass conservation. This is the pressure amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the density amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the velocity amplitude matrix on the leading side of the blade under the condition of enthalpy conservation. This is the pressure amplitude matrix behind the blade under the condition of enthalpy conservation. This is the density amplitude matrix on the trailing side of the blade under the condition of enthalpy conservation. This is the velocity amplitude matrix on the trailing side of the blade under the condition of enthalpy conservation. This is the pressure amplitude matrix at the leading edge of the blade under total pressure lumped-down conditions. This is the density amplitude matrix on the leading side of the blade under total pressure lumped total loss conditions. This is the velocity amplitude matrix at the leading edge of the blade under total pressure lumped loss conditions. This is the pressure amplitude matrix behind the blade under total pressure lumped-down conditions. This is the density amplitude matrix on the trailing side of the blade under total pressure lumped loss conditions. This is the velocity amplitude matrix at the trailing edge of the blade under total pressure lumped loss conditions. This is the pressure amplitude matrix on the leading side of the blade under Kutta conditions. This is the density amplitude matrix on the leading side of the blade under Kuta conditions. This is the velocity amplitude matrix of the leading edge of the blade under Kutta conditions. This is the pressure amplitude matrix behind the blade under Kutta conditions. This is the density amplitude matrix on the trailing side of the blade under Kuta conditions. This is the velocity amplitude matrix on the trailing side of the blade under Kutta conditions. To upload the amplitude matrix of the pressure wave, This is the amplitude matrix of the transmitted pressure wave. This is the first small perturbation amplitude matrix. This is the second smallest perturbation amplitude matrix.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the analytical method for evaluating compressor flow stability under thermal shock distortion as described in any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the analytical method for evaluating compressor flow stability under thermal shock distortion as described in any one of claims 1 to 7.

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