Method and system for carrying out acoustic and aerodynamic design evaluation on blade with acoustic liner structure

Abstract

The invention relates to a method and a system for carrying out acoustic and pneumatic design evaluation on a blade with an acoustic liner structure. Specifically, a hybrid prediction scheme is adopted to carry out acoustic prediction on a blade with an acoustic liner structure, firstly, sound source item information is obtained through numerical simulation, and then an acoustic evaluation effect is obtained by using an acoustic propagation model. In addition, the aerodynamic performance influence is analyzed to determine whether the blade with the acoustic liner structure meets the aerodynamic design requirement or not.

Description

Technical Field

[0001] The present invention relates to the field of engine acoustics, and particularly to a method and system for evaluating the acoustic and aerodynamic design of blades with acoustic lining structures. Background Art

[0002] For high-bypass ratio turbofan engines, the fan noise is the main sound source, and the discrete noise is the main component thereof. To reduce the fan discrete noise at the sound source, the noise can be reduced by adjusting parameters such as the number of fan blades, the sweep angle, and the rotor-stator spacing, or the low-noise design can be achieved through gas dynamic shaping, such as the design of low-noise propeller blades, and noise reduction schemes using accessories such as trailing edge serrations. In terms of the propagation path, the fan noise can be divided into forward-propagating and backward-propagating noises. The forward-propagating noise is currently mainly reduced by laying acoustic linings on the fan casing and nacelle, and the backward-propagating noise is reduced by laying acoustic linings on the outer casing. Generally, the acoustic lining is composed of a perforated plate, a honeycomb, and a back plate, and has excellent noise reduction and vibration damping performance and stable structure. The perforation rate and hole distribution mode of the perforated plate will affect the sound absorption performance. The larger the cavity, the higher the height, and the smaller the wall thickness of the honeycomb core, the better the sound absorption effect. At the unit length, the larger the area of the laid acoustic lining, the better the sound absorption effect.

[0003] With the continuous improvement of the airworthiness noise requirements, in order to further increase the noise reduction amount of the backward-propagating noise and improve the sound absorption effect, in addition to arranging on the casing, a scheme of arranging acoustic linings on the outer stator blades to improve the sound absorption effect has also been proposed, which introduces difficulties in the evaluation of the subsequent acoustic noise reduction effect. For traditional outer stator blades, the wall surface is a hard wall. If an acoustic lining structure is introduced into the outer stator blades, a perforated structure will be introduced on the blade wall surface. When evaluating the acoustics of such a structure, different from the traditional hard wall, boundary conditions and pressure distribution changes will occur. How to measure this problem is a problem that needs to be considered.

[0004] Currently, the prediction of rotor-stator interaction tonal noise generally mainly falls into three categories of methods: empirical prediction models, which have poor versatility and require a large number of engine sample data to correct the model to meet the requirements of engineering applications; analytical prediction models, which require a deep understanding of the generation mechanism and theory of rotor-stator interaction tonal noise, and the disadvantage is that the model has many simplifications and assumptions and cannot consider details, resulting in deviations in engineering applications; numerical calculation problems, which can fully depict details, but the disadvantage is that the required computing resources and configuration requirements are relatively high.

[0005] Therefore, a system capable of improving the defects in the prior art is needed. Summary of the Invention

[0006] The present invention content is provided to introduce some concepts in a simplified form that will be further described in the following detailed implementation section. The present invention content is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to assist in determining the scope of the claimed subject matter.

[0007] Aiming at the technical problems in the prior art, the present invention takes into account the influence of blade wall perforation and numerical analysis problems, and balances computational accuracy and computational efficiency, and proposes a numerical hybrid prediction method for acoustic prediction of blades with acoustic liners. Specifically, in the present invention, high-precision numerical simulation of CFD (Computational Fluid Dynamics) is used for the sound source part by performing acoustic boundary condition processing on the part with acoustic liners on the wall and three-dimensional numerical simulation of the flow field, so as to obtain the acoustic evaluation effect by using the sound propagation model. In addition, the present invention also analyzes the influence on aerodynamic performance by simplifying the geometric structure of the blade with acoustic liners to determine whether the blade with acoustic liner structure meets the aerodynamic design requirements.

[0008] In an embodiment of the present invention, a method for acoustic and aerodynamic design evaluation of blades with acoustic liner structures is provided, including:

[0009] Performing acoustic boundary condition processing on the blade with acoustic liner;

[0010] Based on this acoustic boundary condition processing, performing three-dimensional numerical simulation on the flow field of the blade with acoustic liner to obtain the pressure pulsation distribution on the wall of the blade with acoustic liner;

[0011] By using this pressure pulsation distribution as the source term of the sound source, establishing an integral equation based on the duct sound field theory to obtain the sound field in the duct;

[0012] Judging whether the sound field in the duct meets the acoustic design requirements;

[0013] Performing simplification processing on the geometric structure of the blade with acoustic liner;

[0014] Based on this simplification processing, performing three-dimensional numerical simulation on the flow field of the geometric structure to obtain the influence of the geometric structure on the flow field; and

[0015] Judging whether this influence meets the aerodynamic design requirements.

[0016] In an embodiment of the present invention, the wall of the blade with acoustic liner has perforations and is filled with a honeycomb structure inside, and the wall of the blade with acoustic liner includes a perforated area and a non-perforated area, and the blade with acoustic liner includes a single-sided perforated blade and a double-sided perforated blade.

[0017] In the above embodiments of the present invention, processing the acoustic boundary conditions of the vane with acoustic lining includes defining the perforated region of the wall surface of the vane with acoustic lining as an acoustic impedance boundary condition and defining the non-perforated region as a rigid wall boundary condition.

[0018] In the above embodiments of the present invention, simplifying the geometric structure of the vane with acoustic lining includes simplifying the geometric structure into a solid vane with through holes and without the honeycomb structure, and wherein:

[0019] For the single-sided perforated vane, the diameter of the through hole is the diameter of the perforation on the single-side wall surface and the depth of the through hole is the sum of the thickness of the perforation on the single-side wall surface and the thickness of the honeycomb structure; and

[0020] For the double-sided perforated vane, the diameter of the through hole is the diameter of the perforation and the depth of the through hole is the sum of the thickness of the perforation on the double-side wall surfaces and the thickness of the honeycomb structure.

[0021] In one embodiment of the present invention, the three-dimensional numerical simulation includes three-dimensional unsteady simulation and three-dimensional steady simulation.

[0022] In one embodiment of the present invention, obtaining the sound field in the duct includes calculating the sound field with flow to determine the sound power level.

[0023] In the above embodiments of the present invention, further determining whether the sound field in the duct meets the acoustic design requirements includes determining whether the sound power level is less than or equal to the sound power level threshold, and the method further includes determining that the sound field in the duct does not meet the acoustic design requirements and redesigning the vane with acoustic lining when the sound power level is greater than the sound power level threshold.

[0024] In the above embodiments of the present invention, performing three-dimensional numerical simulation on the flow field of the geometric structure includes performing grid processing on the perforated region, and the grid processing further includes using O-type grids for the perforations in the perforated region and using H-type grids for the rest of the perforated region.

[0025] In one embodiment of the present invention, the influence includes flow rate and pressure ratio.

[0026] In the above embodiments of the present invention, further determining whether the influence meets the aerodynamic design requirements includes:

[0027] Determining whether the deviation of the flow rate from the flow rate reference is within the flow rate deviation threshold; and

[0028] Determining whether the pressure ratio is higher than or equal to the pressure ratio reference and whether the deviation from the pressure ratio reference is within the pressure ratio deviation threshold.

[0029] In the above embodiment of the present invention, the method further includes determining that the influence does not meet the aerodynamic design requirements and redesigning the lined vane when it is determined that the deviation of the flow rate from the flow rate reference is not within the flow rate deviation threshold or it is determined that the pressure ratio is lower than the pressure ratio reference or the deviation of the pressure ratio from the pressure ratio reference is not within the pressure ratio deviation threshold.

[0030] In another embodiment of the present invention, there is provided a system for acoustic and aerodynamic design evaluation of a vane with a lining structure, including:

[0031] An acoustic design evaluation device configured to:

[0032] Perform acoustic boundary condition processing on the lined vane;

[0033] Perform three-dimensional numerical simulation on the flow field of the lined vane based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the lined vane;

[0034] Establish an integral equation based on the pipe sound field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the sound field in the pipe; and

[0035] Judge whether the sound field in the pipe meets the acoustic design requirements; and

[0036] An aerodynamic design evaluation device configured to:

[0037] Perform simplification processing on the geometric structure of the lined vane;

[0038] Perform three-dimensional numerical simulation on the flow field of the geometric structure based on the simplification processing to obtain the influence of the geometric structure on the flow field; and

[0039] Judge whether the influence meets the aerodynamic design requirements.

[0040] In an embodiment of the present invention, the wall surface of the lined vane has perforations and is filled with a honeycomb structure inside, and wherein the wall surface of the lined vane includes a perforated area and a non-perforated area, and the lined vane includes a single-sided perforated vane and a double-sided perforated vane.

[0041] In the above embodiment of the present invention, the acoustic design evaluation device is further configured to perform acoustic boundary condition processing on the lined vane by defining the perforated area of the wall surface of the lined vane as an acoustic impedance boundary condition and defining the non-perforated area as a hard wall boundary condition.

[0042] In the above embodiment of the present invention, the aerodynamic design evaluation device is further configured to perform simplification processing on the geometric structure of the lined vane by simplifying the geometric structure into a solid vane with through holes and without the honeycomb structure, and wherein:

[0043] For the single-sided perforated vane, the diameter of the through-hole is the diameter of the perforation on the single side wall surface, and the depth of the through-hole is the sum of the thickness of the perforation on the single side wall surface and the thickness of the honeycomb structure; and

[0044] For the double-sided perforated vane, the diameter of the through-hole is the diameter of the perforation, and the depth of the through-hole is the sum of the thickness of the perforation on the double side wall surfaces and the thickness of the honeycomb structure.

[0045] In yet another embodiment of the present invention, there is provided a computer-readable medium including instructions that, when executed, cause a processor to perform the following operations:

[0046] Perform acoustic boundary condition processing on the vane with acoustic lining;

[0047] Perform three-dimensional numerical simulation on the flow field of the vane with acoustic lining based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the vane with acoustic lining;

[0048] Establish an integral equation based on the duct acoustic field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the acoustic field in the duct;

[0049] Determine whether the acoustic field in the duct meets the acoustic design requirements;

[0050] Perform simplification processing on the geometric structure of the vane with acoustic lining;

[0051] Perform three-dimensional numerical simulation on the flow field of the geometric structure based on the simplification processing to obtain the influence of the geometric structure on the flow field; and

[0052] Determine whether the influence meets the aerodynamic design requirements.

[0053] After studying the following description of specific exemplary embodiments of the present invention in conjunction with the accompanying drawings, other aspects, features, and embodiments of the present invention will be apparent to those of ordinary skill in the art. Although the features of the present invention may be discussed below with respect to certain embodiments and drawings, all embodiments of the present invention may include one or more of the advantageous features discussed herein. In other words, although one or more embodiments may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various embodiments of the present invention discussed herein. In a similar manner, although the exemplary embodiments may be discussed below as device, system, or method embodiments, it should be understood that such exemplary embodiments may be implemented in various devices, systems, and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] To understand the manner in which the above - stated features of the present disclosure are used in detail, the content briefly outlined above can be described more specifically with reference to various aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings only illustrate certain typical aspects of the present disclosure and should not be considered as limiting its scope, because the description may allow other equally effective aspects.

[0055] Figure 1 FIG. shows a schematic block diagram of a system for acoustic and aerodynamic design evaluation of a blade with a lined structure according to an embodiment of the present disclosure.

[0056] Figure 2 FIG. shows a schematic diagram of acoustic boundary condition processing for a lined blade according to an embodiment of the present disclosure.

[0057] Figure 3 FIG. shows a schematic diagram of simplifying the geometry of a single - sided perforated blade with a lined structure according to an embodiment of the present disclosure.

[0058] Figure 4 FIG. shows a schematic diagram of simplifying the geometry of a double - sided perforated blade with a lined structure according to an embodiment of the present disclosure.

[0059] Figure 5 FIG. shows a schematic diagram of meshing a perforated region according to an embodiment of the present disclosure.

[0060] Figure 6 FIG. shows a flowchart of a method for acoustic and aerodynamic design evaluation of a blade with a lined structure according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0061] The following will describe each embodiment in more detail with reference to the accompanying drawings that form a part of the present invention and illustrate various specific exemplary embodiments. However, the embodiments can be implemented in many different forms and should not be construed as limiting the embodiments set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be thorough and complete, and the scope of these embodiments will be fully conveyed to those of ordinary skill in the art. The embodiments can be implemented as a method, a system, or a device. Thus, these embodiments can take the form of a hardware implementation, a full - software implementation, or an implementation combining software and hardware aspects. Therefore, the following detailed description is not restrictive.

[0062] The steps in each flowchart can be executed by hardware (e.g., a processor, an engine, a memory, a circuit), software (e.g., an operating system, an application, a driver, machine / processor - executable instructions), or a combination thereof. As those of ordinary skill in the art will understand, the methods involved in the embodiments may include more or fewer steps than those shown.

[0063] In view of the defects in the prior art, the present invention adopts a hybrid prediction scheme to conduct acoustic prediction on the blade with a liner structure. The structure of the blade with a liner structure is relatively complex, with perforations on the blade wall and honeycombs filled inside. If a complete model of its structure is built, the computational amount and difficulty are extremely huge. Considering the actual engineering requirements, it is necessary to simplify it to reduce the computational time and difficulty and achieve the prediction purpose. The present invention adopts a hybrid prediction scheme. First, the sound source term information is obtained through numerical simulation, and then the acoustic evaluation effect is obtained by using the sound propagation model.

[0064] Specifically, the present invention provides an acoustic numerical prediction method for a blade with a liner structure, including performing acoustic boundary condition processing on the part of the wall with openings and a liner; and conducting three-dimensional numerical simulation on the flow field to obtain the pressure pulsation distribution on the blade wall, which is the source term of the sound source, and establishing an integral equation through the duct sound field theory to obtain the sound field effect in the duct, so as to obtain the acoustic evaluation effect by using the sound propagation model.

[0065] In addition, the present invention also conducts aerodynamic design analysis on the blade with a liner to determine whether it meets the aerodynamic design requirements, including simplifying the blade with a single-sided perforated structure into a solid blade with a hole structure, and simplifying the blade with a double-sided perforated structure into a solid blade with a through-hole structure. The mesh needs to be processed in the perforated area, and three-dimensional numerical simulation is conducted on the flow field to obtain the influence analysis of the flow field.

[0066] In the following, various aspects of the present disclosure will be described in more detail and comprehensively through block diagrams and method flowcharts.

[0067] Figure 1 FIG. shows a schematic block diagram of a system 100 for acoustic and aerodynamic design evaluation of a blade with a liner structure according to an embodiment of the present disclosure.

[0068] As Figure 1 shown, the system 100 may include an acoustic design evaluation device 102 and an aerodynamic design evaluation device 104. The following will describe these two devices in detail in combination with Figures 2 to 5 this.

[0069] In the present invention, the wall of the blade with a liner may have perforations and may be filled with a honeycomb structure inside, and the wall of the blade with a liner may include a perforated area and a non-perforated area. The blade with a liner may include a single-sided perforated blade and a double-sided perforated blade.

[0070] In one embodiment of the present invention, considering that the computational amount and difficulty of completely modeling the geometric structure of the acoustic-lined blade in the present invention are extremely large, according to the actual engineering requirements, it is necessary to simplify the geometric structure to reduce the computational duration and difficulty so as to achieve the prediction purpose. Thus, the acoustic design evaluation device 102 can be configured to perform acoustic boundary condition processing on the acoustic-lined blade. As Figure 2 shown, the wall surface of the acoustic-lined blade may include a perforated region 32 and a non-perforated region 31. In the above embodiment of the present invention, the acoustic design evaluation device 102 can be further configured to perform acoustic boundary condition processing on the acoustic-lined blade by defining the perforated region 32 of the wall surface of the acoustic-lined blade as an acoustic impedance boundary condition and defining the non-perforated region 31 as a rigid wall boundary condition.

[0071] In one embodiment of the present invention, the acoustic design evaluation device 102 can also be configured to perform three-dimensional numerical simulation on the flow field of the acoustic-lined blade based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the acoustic-lined blade. In the above embodiment, the three-dimensional numerical simulation may include three-dimensional unsteady simulation and three-dimensional steady simulation. In another embodiment of the present invention, in addition to the pressure pulsation distribution, the acoustic design evaluation device 102 can also be configured to obtain geometric parameters, average mainstream flow parameters, etc. of the acoustic-lined blade.

[0072] In one embodiment of the present invention, the acoustic design evaluation device 102 can also be configured to establish an integral equation based on the duct acoustic field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the acoustic field in the duct. In the above embodiment, the acoustic design evaluation device 102 can be further configured to obtain the acoustic field in the duct by calculating the acoustic field with flow to determine the sound power level. By way of example and not limitation, software tools such as actran and any other suitable tools can be used to perform three-dimensional numerical simulation to calculate the acoustic field with flow. As can be understood by those skilled in the art, the duct acoustic field theory and integral equation in the present invention are not limited to any specific duct acoustic field theory and any specific integral equation, but any suitable duct acoustic field theory and integral equation can be used to obtain the acoustic field in the duct.

[0073] In one embodiment of the present invention, the acoustic design evaluation device 102 may also be configured to determine whether the sound field in the duct meets the acoustic design requirements. In the above embodiment, the acoustic design evaluation device 102 may be further configured to determine whether the sound field in the duct meets the acoustic design requirements by determining whether the sound power level is less than or equal to the sound power level threshold. And in another embodiment, the acoustic design evaluation device 102 may be further configured to determine that the sound field in the duct does not meet the acoustic design requirements and prompt that the sound-lined blade needs to be redesigned when the sound power level is greater than the sound power level threshold. As those skilled in the art can understand, the sound power level threshold can be set according to actual needs and is not limited to any specific sound power level threshold. And the conditions under which the acoustic design requirements are met or not can also be set according to actual needs and are not limited to any specific conditions.

[0074] In the present invention, the noise reduction means adopted (i.e., the sound-lined blade) should not affect the aerodynamic performance as much as possible. Considering that the actual structural result of the sound-lined blade is relatively complex, the geometric structure of the model needs to be processed during calculation so that the influence of the perforated structure on the wall surface of the sound-lined blade on the flow performance can be equivalently evaluated.

[0075] Therefore, in one embodiment of the present invention, the aerodynamic design evaluation device 104 may be configured to simplify the geometric structure of the sound-lined blade. In the above embodiment, the aerodynamic design evaluation device 104 may be further configured to simplify the geometric structure of the sound-lined blade by simplifying the geometric structure into a solid blade with through holes and without the honeycomb structure.

[0076] Specifically, Figure 3 shows a schematic diagram of simplifying the geometric structure of a single-sided perforated blade with a sound-lined structure according to an embodiment of the present disclosure. As Figure 3 shown, for the single-sided perforated structure blade (11), it is a closed cavity for the flow, as shown in the left figure a) in Figure 3 , in which the structure includes a blade wall surface with a perforated structure (111), and a closed cavity is formed by the blade wall surface without perforations (114), the honeycomb (113) and the perforations (112). For the convenience of carrying out calculations, considering the scale of the perforations, which is generally in millimeters, it is simplified into a solid blade with a through-hole structure (12), as shown in the right figure b) in Figure 3 . A hole (121) is drilled in the blade wall surface, the diameter of the through hole is the diameter of the perforation (112), and the depth of the through hole is the sum of the thickness of the perforation (112) and the thickness of the honeycomb (113). That is, for the single-sided perforated blade, the diameter of the through hole can be the diameter of the perforation on the single side wall surface and the depth of the through hole is the sum of the thickness of the perforation on the single side wall surface and the thickness of the honeycomb structure.

[0077] Figure 4A schematic diagram showing the simplified treatment of the geometry of a double-sided perforated vane with a sound lining structure according to an embodiment of the present disclosure is shown. As Figure 4 shown, for the double-sided perforated structure vane (21), as Figure 4 shown in the left figure a) in Figure 4 , it includes a wall surface (211), perforations (212), and honeycombs (213). For the convenience of carrying out calculations, it is simplified to a solid vane with a through-hole structure (22), as shown in the right figure b) in . The vane has a through-hole, the diameter of the through-hole is the diameter of the perforation (212), and the depth of the through-hole is the sum of the thickness of the perforation (212) and the thickness of the honeycomb (213). That is, for this double-sided perforated vane, the diameter of the through-hole can be the diameter of the perforation and the depth of the through-hole is the sum of the thickness of the perforations on the double side walls and the thickness of the honeycomb structure.

[0078] After completing the simplified treatment of the geometry of the vane with a sound lining, in an embodiment of the present invention, the aerodynamic design evaluation device 104 can also be configured to perform a three-dimensional numerical simulation on the flow field of the geometry based on this simplified treatment to obtain the influence of the geometry on the flow field. In the above embodiment, the three-dimensional numerical simulation can include three-dimensional unsteady simulation and three-dimensional steady simulation. The steady calculation takes less time and can obtain quick feedback; the unsteady calculation can capture more details to support subsequent optimization.

[0079] In another embodiment of the present invention, considering that the scale of the perforations is small, in order to ensure the grid accuracy, the grid needs to be processed in the perforated area (such as Figure 2 the perforated area 32 in

[0080] Figure 5 A schematic diagram showing the grid processing of the perforated area according to an embodiment of the present disclosure is shown. As Figure 5 shown, a combination of an O-type grid (41) and an H-grid (42) is selected to divide the perforated area. In various embodiments, the aerodynamic design evaluation device 104 can be further configured to perform grid processing by using an O-type grid for the perforations in the perforated area and an H-type grid for the rest of the perforated area.

[0081] In an embodiment of the present invention, the aerodynamic design evaluation device 104 can also be configured to determine whether the influence meets the aerodynamic design requirements. In an embodiment of the present invention, the influence can include flow rate and pressure ratio. As those skilled in the art can understand, in other embodiments of the present invention, the influence can include any other suitable parameters and is not limited to any specific parameters.

[0082] In the above embodiments of the present invention, the pneumatic design evaluation device 104 may be further configured to determine whether the influence meets the pneumatic design requirements through the following operations: determining whether the deviation between the flow rate and the flow rate reference is within the flow rate deviation threshold; determining whether the pressure ratio is higher than or equal to the pressure ratio reference and whether the deviation from the pressure ratio reference is within the pressure ratio deviation threshold; and in the case where it is determined that the deviation between the flow rate and the flow rate reference is not within the flow rate deviation threshold or it is determined that the pressure ratio is lower than the pressure ratio reference or the deviation from the pressure ratio reference is not within the pressure ratio deviation threshold, determining that the influence does not meet the pneumatic design requirements and prompting that the lined blade needs to be redesigned.

[0083] Figure 6 FIG. 4 shows a flowchart of a method 600 for acoustic and pneumatic design evaluation of a lined structure blade according to an embodiment of the present disclosure. In an embodiment of the present invention, the wall surface of the lined blade may have perforations and may be filled with a honeycomb structure inside, and the wall surface of the lined blade may include a perforated area and a non-perforated area, and the lined blade may include a single-sided perforated blade and a double-sided perforated blade.

[0084] As Figure 6 shown, method 600 begins at step 602 to perform acoustic boundary condition processing on the lined blade. In an embodiment of the present invention, performing acoustic boundary condition processing on the lined blade may include defining the perforated area of the wall surface of the lined blade as an acoustic impedance boundary condition and defining the non-perforated area as a rigid wall boundary condition.

[0085] Next, method 600 continues to step 604 to perform a three-dimensional numerical simulation of the flow field of the lined blade based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the lined blade. In an embodiment of the present invention, the three-dimensional numerical simulation may include three-dimensional unsteady simulation and three-dimensional steady simulation.

[0086] Subsequently, method 600 continues to step 606 to establish an integral equation based on the duct sound field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the sound field in the duct. In an embodiment of the present invention, obtaining the sound field in the duct may include calculating the sound field with flow to determine the sound power level.

[0087] Then, method 600 continues to step 608 to determine whether the sound field in the duct meets the acoustic design requirements. In an embodiment of the present invention, determining whether the sound field in the duct meets the acoustic design requirements may further include determining whether the sound power level is less than or equal to the sound power level threshold, and method 600 may optionally further include determining that the sound field in the duct does not meet the acoustic design requirements and redesigning the lined blade in the case where the sound power level is greater than the sound power level threshold.

[0088] Next, method 600 proceeds to step 610 to simplify the geometry of the lined vane. In one embodiment of the present invention, simplifying the geometry of the lined vane may include simplifying the geometry to a solid vane with through-holes and without the honeycomb structure, and wherein for a single-sided perforated vane, the diameter of the through-hole may be the diameter of the perforation on the single sidewall surface and the depth of the through-hole may be the sum of the thickness of the perforation on the single sidewall surface and the thickness of the honeycomb structure, and for a double-sided perforated vane, the diameter of the through-hole may be the diameter of the perforation and the depth of the through-hole may be the sum of the thickness of the perforations on the double sidewall surfaces and the thickness of the honeycomb structure.

[0089] Subsequently, method 600 proceeds to step 612 to perform a three-dimensional numerical simulation of the flow field of the geometry based on the simplification to obtain the influence of the geometry on the flow field. In one embodiment of the present invention, performing a three-dimensional numerical simulation of the flow field of the geometry may include meshing the perforated region, and the meshing may further include using O-type meshes for the perforations in the perforated region and H-type meshes for the remaining part of the perforated region.

[0090] Finally, method 600 proceeds to step 614 to determine whether the influence meets the aerodynamic design requirements. In one embodiment of the present invention, the influence may include flow rate and pressure ratio. In the above embodiment of the present invention, determining whether the influence meets the aerodynamic design requirements may further include: determining whether the deviation of the flow rate from the flow rate reference is within the flow rate deviation threshold; determining whether the pressure ratio is higher than or equal to the pressure ratio reference and whether the deviation from the pressure ratio reference is within the pressure ratio deviation threshold; and in the case where it is determined that the deviation of the flow rate from the flow rate reference is not within the flow rate deviation threshold or it is determined that the pressure ratio is lower than the pressure ratio reference or the deviation from the pressure ratio reference is not within the pressure ratio deviation threshold, determining that the influence does not meet the aerodynamic design requirements and redesigning the lined vane.

[0091] As can be understood by those skilled in the art, the aerodynamic design evaluation operation in the present invention may be performed simultaneously with the acoustic design evaluation operation or before or after the acoustic design evaluation operation, depending on the specific implementation.

[0092] In summary, the present invention adopts a numerical hybrid prediction method, taking into account both computational accuracy and computational efficiency, facilitating engineering application and promotion. For complex vane structures with a lined structure, a method for acoustic and aerodynamic design evaluation of lined vanes is proposed. By this method, the noise reduction effect is predicted, so as to support the optimization of the scheme and reduce the processing and test costs.

[0093] The foregoing has described, with reference to block diagrams and / or operational descriptions of methods, systems, and computer program products according to embodiments of the present invention. The functions / actions noted in the blocks may occur in a different order than any flowchart shown. For example, two blocks shown in succession may in fact be executed substantially concurrently depending on the functionality / action involved, or the blocks may sometimes be executed in the reverse order.

[0094] As described above, the foregoing is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for acoustic and aerodynamic design evaluation of a blade with a lining structure, comprising: performing acoustic boundary condition processing on the blade with a lining; performing three-dimensional numerical simulation on the flow field of the blade with a lining based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the blade with a lining; establishing an integral equation based on the duct acoustic field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the acoustic field in the duct; judging whether the acoustic field in the duct meets the acoustic design requirements; performing simplification processing on the geometric structure of the blade with a lining; performing three-dimensional numerical simulation on the flow field of the geometric structure based on the simplification processing to obtain the influence of the geometric structure on the flow field; and judging whether the influence meets the aerodynamic design requirements.

2. The method according to claim 1, wherein the wall surface of the blade with a lining has perforations and is filled with a honeycomb structure inside, and wherein the wall surface of the blade with a lining includes a perforated area and a non-perforated area, and the blade with a lining includes a single-sided perforated blade and a double-sided perforated blade.

3. The method according to claim 2, wherein performing acoustic boundary condition processing on the blade with a lining includes defining the perforated area of the wall surface of the blade with a lining as an acoustic impedance boundary condition and defining the non-perforated area as a hard wall boundary condition, and performing simplification processing on the geometric structure of the blade with a lining includes simplifying the geometric structure into a solid blade with through holes and without the honeycomb structure, and wherein: for the single-sided perforated blade, the diameter of the through hole is the diameter of the perforation on the single side wall surface and the depth of the through hole is the sum of the thickness of the perforation on the single side wall surface and the thickness of the honeycomb structure; and for the double-sided perforated blade, the diameter of the through hole is the diameter of the perforation and the depth of the through hole is the sum of the thickness of the perforations on the double side wall surfaces and the thickness of the honeycomb structure.

4. The method according to claim 1, wherein obtaining the acoustic field in the duct includes calculating the acoustic field with flow to determine the sound power level, and judging whether the acoustic field in the duct meets the acoustic design requirements further includes determining whether the sound power level is less than or equal to the sound power level threshold, and wherein the method further includes determining that the acoustic field in the duct does not meet the acoustic design requirements and redesigning the blade with a lining in the case where the sound power level is greater than the sound power level threshold.

5. The method according to claim 1, wherein performing three-dimensional numerical simulation on the flow field of the geometric structure includes performing grid processing on the perforated area, and the grid processing further includes using O-type grids for the perforations in the perforated area and using H-type grids for the remaining part of the perforated area.

6. The method according to claim 1, wherein the influence includes flow rate and pressure ratio, and judging whether the influence meets the aerodynamic design requirements further includes: determining whether the deviation of the flow rate from the flow rate reference is within the flow rate deviation threshold; and determining whether the pressure ratio is higher than or equal to the pressure ratio reference and whether the deviation from the pressure ratio reference is within the pressure ratio deviation threshold.

7. The method according to claim 6, further comprising, when it is determined that the deviation of the flow rate from the flow rate reference is not within the flow rate deviation threshold, or it is determined that the pressure ratio is lower than the pressure ratio reference or the deviation of the pressure ratio from the pressure ratio reference is not within the pressure ratio deviation threshold, determining that the influence does not meet the aerodynamic design requirements and redesigning the vane with acoustic lining.

8. A system for acoustic and aerodynamic design evaluation of a vane with an acoustic lining structure, comprising: an acoustic design evaluation device configured to: perform acoustic boundary condition processing on the vane with acoustic lining; perform three-dimensional numerical simulation on the flow field of the vane with acoustic lining based on the acoustic boundary condition processing to obtain the pressure pulsation distribution on the wall surface of the vane with acoustic lining; establish an integral equation based on the duct sound field theory by using the pressure pulsation distribution as the source term of the sound source to obtain the sound field in the duct; and judge whether the sound field in the duct meets the acoustic design requirements; and an aerodynamic design evaluation device configured to: perform simplification processing on the geometric structure of the vane with acoustic lining; perform three-dimensional numerical simulation on the flow field of the geometric structure based on the simplification processing to obtain the influence of the geometric structure on the flow field; and judge whether the influence meets the aerodynamic design requirements.

9. The system according to claim 8, wherein the wall surface of the vane with acoustic lining has perforations and is filled with a honeycomb structure inside, and wherein the wall surface of the vane with acoustic lining includes a perforated area and a non-perforated area, and the vane with acoustic lining includes a single-sided perforated vane and a double-sided perforated vane.

10. The system according to claim 9, wherein the acoustic design evaluation device is further configured to perform acoustic boundary condition processing on the vane with acoustic lining by defining the perforated area on the wall surface of the vane with acoustic lining as an acoustic impedance boundary condition and defining the non-perforated area as a rigid wall boundary condition, and the aerodynamic design evaluation device is further configured to perform simplification processing on the geometric structure of the vane with acoustic lining by simplifying the geometric structure into a solid vane with through holes and without the honeycomb structure, and wherein: for the single-sided perforated vane, the diameter of the through hole is the diameter of the perforation on the single side wall surface, and the depth of the through hole is the sum of the thickness of the perforation on the single side wall surface and the thickness of the honeycomb structure; and for the double-sided perforated vane, the diameter of the through hole is the diameter of the perforation, and the depth of the through hole is the sum of the thickness of the perforations on the double side wall surfaces and the thickness of the honeycomb structure.

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