A method for designing a compressor stator vane

Abstract

The application discloses an aero-engine technical field, and relates to a compressor guide vane design method. The method forms a design allowable envelope of a guide vane by designing a guide vane profile, and divides optimization of an anti-icing design of the guide vane into two levels. The first level is improvement of a normal guide vane internal cavity structure. When the first level optimization cannot meet the anti-icing requirement of the guide vane, the second level optimization is performed. The second level optimization performs structural optimization on the guide vane profile and / or the internal cavity structure in the guide vane profile design allowable envelope according to the result of the first level optimization, increases the optimization space of the guide vane, does not need to increase the anti-icing bleed air flow of the guide vane, reduces the influence on the performance of the engine, and is beneficial to rapid iterative design of the engine.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engines, and in particular to a compressor guide vane design method. Background Art

[0002] The zero-stage guide vanes of an aircraft engine compressor must guide the airflow entering the compressor to meet performance requirements. This is achieved by shaping the compressor's external blade profile. Furthermore, the zero-stage guide vanes are in direct contact with the atmosphere. Liquid water in the cold atmosphere can impinge on the zero-stage blades and form ice. Ice on these blades can affect engine operation and, in severe cases, damage the engine and compromise flight safety. Ice formation on the zero-stage blades is typically prevented by introducing a certain amount of hot air.

[0003] During the design process of traditional guide vanes, the blade shape of the guide vanes is first designed according to the performance requirements of the compressor. Then, after analyzing the anti-icing requirements of the guide vanes, the hot air flow cavity inside the guide vanes is designed. With the continuous updating of aircraft engines, the performance requirements of aircraft engines are getting higher and higher. When designing the hot air flow cavity inside the guide vanes, it is often encountered that it is difficult to meet the anti-icing requirements of the guide vanes by improving the inner cavity. The current mainstream solution is to introduce more hot air flow and introduce higher temperature compressed air. This requires more hot air to be drawn out from the engine for anti-icing of the guide vanes, which will reduce the overall performance of the engine and is not conducive to the rapid iterative design of the engine.

[0004] Based on this, the present invention designs a compressor guide vane design method to solve the above problems. Summary of the Invention

[0005] To achieve the above-mentioned object, the present invention provides the following technical solution: a compressor guide vane design method, characterized by comprising:

[0006] S1, design the initial blade profile that meets the compressor performance requirements;

[0007] S2: Analyze the guide vane anti-icing requirements within the operating envelope and determine the guide vane anti-icing area and anti-icing hot gas flow rate;

[0008] S3: Select a baseline inner cavity configuration to perform initial inner cavity structure design for the guide vanes. Perform a matching analysis between the hot gas flow rate and the inner cavity structure to ensure that the designed inner cavity flow resistance and exhaust area meet the hot gas flow requirements.

[0009] Perform thermal balance calculation on the guide vanes and analyze the guide vane anti-icing effect within the operating envelope. If the design requirement of the guide vane blade minimum temperature > 0°C is met, proceed directly to step S5.

[0010] If the design requirements are not met, proceed to step S4;

[0011] S4, guide vane design optimization:

[0012] The first level optimization, under the premise that the hot gas exhaust pressure margin allows, improves the guide vane cavity structure design to increase the internal heat exchange capacity to enhance the anti-icing heating effect. If the final guide vane heat balance calculation meets the design requirement of the guide vane blade minimum temperature > 0°C, then directly proceed to step S5. If it does not meet the design requirement, then proceed to the second level optimization;

[0013] The second level of optimization is to improve the blade shape design and / or inner cavity structure of the guide vane and perform the guide vane thermal balance calculation according to the guide vane thermal balance calculation results after the first level of optimization.

[0014] S5, output design results.

[0015] As a further solution of the present invention, in step S1, designing the initial blade profile of the guide vane includes:

[0016] S11, using conventional axial flow stator blade design methods, design an initial blade profile that meets aerodynamic performance requirements based on the compressor guide vane attack angle characteristics and flow losses;

[0017] S12, a parameter sensitivity analysis is conducted on the leading edge diameter, trailing edge diameter, and mid-chord inscribed circle diameter that affect the internal structure of the hot air flow anti-icing cavity of the guide vane, to obtain the influence range of the guide vane size on the guide vane angle of attack characteristics and flow loss, and to form the design envelope of the guide vane.

[0018] As a further solution of the present invention, in step S2, the steps of determining the guide vane anti-icing area and the anti-icing hot gas flow are as follows:

[0019] S21: Obtain typical anti-icing requirement operating conditions within the engine operating envelope. Simultaneously, referencing the guide vane's angle of attack characteristics, perform guide vane ice accumulation analysis to determine the areas where the guide vanes require anti-icing.

[0020] S22: Based on the prevailing operating conditions of the compressor guide vanes, the anti-icing bleed air status, and the distribution of the guide vanes on the windward side, the anti-icing demand analysis method for the inlet guide vanes is applied to determine the anti-icing hot gas flow rate for the guide vanes.

[0021] As a further solution of the present invention, in step S3, the matching analysis method of the hot gas flow rate and the inner cavity structure is:

[0022] By constructing a flow network in the guide vane cavity and applying the matching analysis method of internal flow resistance and flow rate, the air inlet, internal flow resistance distribution, outflow area of ​​the exhaust window and the minimum throttling area under a given hot gas flow rate are determined.

[0023] As a further solution of the present invention, in step S4, the first level optimization includes:

[0024] S41, increase the throttle area of the trailing edge exhaust window, reduce the outflow resistance of hot gas at this place;

[0025] S42, increase the flow length of the inner cavity hot gas flow, modify the radial single flow to radial double flow, increase the inner cavity flow path;

[0026] S43, for the area with insufficient anti-icing ability, increase the inner cavity spoiler column array.

[0027] As a further scheme of the present application, in step S4, when the second level optimization is performed, if the area with insufficient anti-icing ability is the trailing edge area of the blade, the chord length of the blade in the radial direction of the trailing edge is shortened to reduce the area of the blade trailing edge icing, if the main problem of the inner cavity improvement design is the excessive flow resistance of the inner cavity hot gas, the leading edge diameter and / or the trailing edge diameter and / or the diameter of the inscribed circle in the middle chord of the guide vane are increased, if the inner cavity faces the problem of insufficient heat exchange capacity due to excessive inner cavity size, the diameter of the inscribed circle in the middle chord of the guide vane is reduced.

[0028] As a further scheme of the present application, in step S4, when the second level optimization is performed, the guide vane profile design needs to be within the design allowable envelope.

[0029] The present application has the following beneficial effects:

[0030] The method forms the design allowable envelope of the guide vane when designing the profile of the guide vane, and divides the optimization of the anti-icing design of the guide vane into two levels, the first level is the improvement of the normal guide vane inner cavity structure, and when the first level optimization cannot meet the anti-icing requirements of the guide vane, the second level optimization is performed, the second level optimization will perform structural optimization of the profile of the guide vane and / or the inner cavity structure within the design allowable envelope of the guide vane according to the results of the first level optimization, increase the optimization space of the guide vane, without increasing the anti-icing bleed air flow of the guide vane, reduce the impact on the performance of the engine, and is conducive to the rapid iterative design of the engine.

[0031] In addition to the purposes, features and advantages described above, the present application has other purposes, features and advantages. The present application will be further described below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0032] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application, illustrate the preferred embodiments of the application, and assist in explaining the application. In the drawings:

[0033] Figure 1 The flowchart of the method. DETAILED DESCRIPTION

[0034] The embodiments of the present application will be described in detail below with reference to the drawings, but the present application can be implemented in various different ways as defined and covered by the following description.

[0035] Referring to Figure 1 The present application provides a compressor guide vane design method, characterized in that comprising:

[0036] S1, designing an initial blade profile meeting the compressor performance requirements;

[0037] S2, analyzing the guide vane anti-icing requirements within the operating envelope, determining the guide vane anti-icing area and the anti-icing hot gas flow;

[0038] S3, selecting a reference internal cavity configuration to design the initial internal cavity structure of the guide vane, and performing matching analysis of the hot gas flow and the internal cavity structure to ensure that the designed internal cavity flow resistance and exhaust area meet the hot gas flow requirements;

[0039] Performing a thermal balance calculation on the guide vane to analyze the guide vane anti-icing effect within the operating envelope, if the guide vane blade minimum temperature > 0℃ design requirement is met, then directly proceed to step S5;

[0040] If the design requirement is not met, then proceed to step S4;

[0041] S4, guide vane design optimization:

[0042] First level optimization, under the premise that the hot gas exhaust pressure margin is allowed, by improving the guide vane internal cavity structure design, increasing the internal heat exchange capacity, to improve the anti-icing heating effect, if the final guide vane thermal balance calculation meets the guide vane blade minimum temperature > 0℃ design requirement, then directly proceed to step S5, if the design requirement is not met, then proceed to the second level optimization;

[0043] Second level optimization, according to the first level optimization guide vane thermal balance calculation result, improve the guide vane profile design and / or internal cavity structure, and perform guide vane thermal balance calculation;

[0044] S5, output the design result.

[0045] When the guide vane internal cavity structure improvement cannot achieve the required anti-icing effect of the guide vane, then according to the guide vane thermal balance calculation result, the guide vane profile is modified, the guide vane optimization space is increased, and the anti-icing effect of the guide vane can meet the anti-icing requirements of the guide vane without increasing the anti-icing bleed air flow of the guide vane, which can reduce the impact on the engine performance.

[0046] Specifically, in step S1, designing the initial blade profile of the guide vane includes:

[0047] S11, using the conventional axial stator blade design method, on the basis of meeting the compressor guide vane angle of attack characteristics and flow loss, design the initial blade profile that meets the aerodynamic performance;

[0048] S12, for the leading edge diameter, trailing edge diameter, and mid-chord inscribed circle diameter that affect the internal hot gas flow anti-icing cavity structure of the guide vane, parameter sensitivity analysis is carried out to obtain the influence range of guide vane size on guide vane angle of attack characteristics and flow loss, and a design allowable envelope of the guide vane is formed;

[0049] The guide vane profile is designed using the conventional axial stator blade design method, which is prior art and will not be described in detail here. For the leading edge diameter, trailing edge diameter, and mid-chord inscribed circle diameter that affect the internal hot gas flow anti-icing cavity structure of the guide vane, parameter sensitivity analysis is carried out to obtain the influence range of guide vane size on guide vane angle of attack characteristics and flow loss, and a design allowable envelope of the guide vane is formed. This provides a modification range for the guide vane profile in the second level optimization in step S4, preventing excessive modification of the guide vane profile that cannot meet the compressor guide vane angle of attack characteristics and flow loss, to ensure that the final guide vane can meet the anti-icing effect required by the guide vane while also meeting the compressor guide vane angle of attack characteristics and flow loss.

[0050] The design allowable envelope refers to the guide vane angle of attack characteristics and flow loss formed under different guide vane profile parameter combinations that meet the design requirements with a certain margin. During initial design, the margin is not the larger the better, and there are usually a basic margin value. Under this margin condition, there may be many guide vane profile parameter combinations that can meet the requirements, and only one of them (the intermediate parameter state) needs to be selected for further design.

[0051] Specifically, in step S2, the guide vane anti-icing area and anti-icing hot gas flow are determined as follows:

[0052] S21, obtain the typical anti-icing demand operating point in the engine operating envelope, carry out guide vane icing analysis to determine the area that needs to be anti-iced, and determine the anti-icing hot gas flow. In engine design, there are special anti-icing demand operating points that are combined with environmental temperature and atmospheric water content. In general, it is the engine slow running state at minus 20℃, which is usually the most severe anti-icing condition for the guide vane. At the same time, during the guide vane icing analysis, the guide vane angle of attack characteristics need to be considered. The icing area and amount are different at different guide vane angles;

[0053] S22, according to the main flow condition of the compressor guide vane, the anti-icing bleed air state and the distribution of the guide vane windward surface, the anti-icing demand analysis method of the inlet guide vane is applied to determine the anti-icing hot gas flow. If the determined anti-icing hot gas flow exceeds the overall limitation requirement of the engine, the anti-icing bleed air position, anti-icing demand and other related target constraints need to be coordinated.

[0054] The mainstream operating conditions of the compressor guide vanes refer to the fluid operating conditions in the main flow channel of the engine, including the flow rate, pressure and temperature of the mainstream.

[0055] Specifically, in step S3, the reference inner cavity configuration is a commonly used reference configuration;

[0056] Specifically, in step S3, the matching analysis method between the hot gas flow rate and the inner cavity structure is:

[0057] By building an internal flow network and applying the internal flow resistance and flow matching analysis method, the air inlet, internal flow resistance distribution, exhaust window outflow area, and minimum throttling area under a given hot gas flow rate are determined.

[0058] The throttling control of the hot air flow in the guide vane cavity is achieved through the flow resistance design at various locations, ensuring that the hot air flow flowing in the guide vane cavity does not exceed the design allowable requirements.

[0059] Specifically, in step S4, a heat balance calculation is performed on the guide vanes for a typical anti-icing demand operating point within the engine operating envelope. If the design requirement of the guide vane blade minimum temperature > 0°C is met, step S5 is directly performed.

[0060] Normally, during the design phase, calculations and analyses are mainly performed on operating points with relatively severe anti-icing conditions. After the design is completed, verification calculations are performed on other operating points within the envelope.

[0061] Specifically, in step S4, the first level optimization includes:

[0062] S41, increase the throttling area of ​​the exhaust window at the trailing edge to reduce the hot gas outflow resistance at this location;

[0063] S42, increase the flow length of the inner cavity hot gas flow, change the radial single flow to radial double flow, and increase the inner cavity flow stroke;

[0064] S43: For areas with insufficient anti-icing capabilities, an array of inner cavity spoiler columns is added.

[0065] The second level optimization is divided into the following situations:

[0066] When the area with insufficient anti-icing is the trailing edge of the blade, the blade chord length in the trailing edge radius direction is shortened within the design envelope of the guide vane to reduce the ice formation area on the trailing edge of the blade and reduce the anti-icing demand on the guide vane so that the anti-icing effect can meet the design requirements.

[0067] When improving the inner cavity design, the main problem faced is excessive hot air flow resistance in the inner cavity. Therefore, the guide vane design allows the leading edge diameter and / or trailing edge diameter and / or mid-chord inscribed circle diameter of the guide vane to be increased within the envelope, thereby increasing the overall size of the guide vane. Under the condition of unchanged wall thickness, the size of the guide vane inner cavity will also increase accordingly, so that the hydraulic diameter of the guide vane inner cavity can be further increased. At the same hot air flow rate, the hot air flow resistance of the inner cavity is reduced, the heat exchange effect is improved, and the anti-icing effect of the guide vane is enhanced.

[0068] When the inner cavity faces insufficient heat exchange capacity due to its oversized inner cavity size, directly reducing the guide vane inner cavity size will change the guide vane wall thickness, thereby affecting the heat conduction and strength of the blade. Therefore, it is necessary to first reduce the inscribed circle diameter of the guide vane mid-chord area and reduce the guide vane inner cavity size, so that the guide vane inner cavity size can be further reduced while the guide vane wall thickness remains unchanged. At the same hot gas flow rate, the Reynolds number of the inner cavity hot gas channel is increased to enhance the inner cavity heat exchange and increase the anti-icing effect of the guide vane.

[0069] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A compressor guide vane design method, characterized in that: include: S1, design the initial blade profile that meets the compressor performance requirements and forms the design allowable envelope of the guide vanes; S2: Analyze the guide vane anti-icing requirements within the operating envelope and determine the guide vane anti-icing area and anti-icing hot gas flow rate; S3: Select a baseline inner cavity configuration to perform initial inner cavity structure design for the guide vanes. Perform a matching analysis between the hot gas flow rate and the inner cavity structure to ensure that the designed inner cavity flow resistance and exhaust area meet the hot gas flow requirements. Perform thermal balance calculation on the guide vanes and analyze the guide vane anti-icing effect within the operating envelope. If the design requirement of the guide vane blade minimum temperature > 0°C is met, proceed directly to step S5. If the design requirements are not met, proceed to step S4; S4, guide vane design optimization: The first level optimization, under the premise that the hot gas exhaust pressure margin allows, improves the guide vane cavity structure design to increase the internal heat exchange capacity to enhance the anti-icing heating effect. If the final guide vane heat balance calculation meets the design requirement of the guide vane blade minimum temperature > 0°C, then directly proceed to step S5. If it does not meet the design requirement, then proceed to the second level optimization; The first level of optimization includes: S41, increase the throttling area of ​​the exhaust window at the trailing edge to reduce the hot gas outflow resistance at this location; S42, increase the flow length of the inner cavity hot gas flow, change the radial single flow to radial double flow, and increase the inner cavity flow stroke; S43, for areas with insufficient anti-icing capabilities, an array of inner cavity spoiler columns is added; The second level optimization includes improving the blade profile design and / or inner cavity structure of the guide vane and performing the guide vane thermal balance calculation according to the guide vane thermal balance calculation results after the first level optimization; During the second-level optimization, if the area with insufficient anti-icing is the trailing edge of the blade, the blade chord length in the trailing edge radius direction is shortened to reduce the ice area on the trailing edge of the blade. If the internal cavity improvement design mainly faces the problem of excessive internal cavity hot air flow resistance, the leading edge diameter and / or trailing edge diameter and / or mid-chord inscribed circle diameter of the guide vane are increased. If the internal cavity faces insufficient heat exchange capacity due to excessive internal cavity size, the mid-chord inscribed circle diameter of the guide vane is reduced. When performing the second-level optimization, the blade shape design of the guide vane needs to be within the design allowable envelope; S5, output design results.

2. The compressor guide vane design method according to claim 1, characterized in that: In step S1, designing the initial blade profile of the guide vane includes: S11, using conventional axial flow stator blade design methods, design an initial blade profile that meets aerodynamic performance requirements based on the compressor guide vane attack angle characteristics and flow losses; S12, a parameter sensitivity analysis is conducted on the leading edge diameter, trailing edge diameter, and mid-chord inscribed circle diameter that affect the internal structure of the hot air flow anti-icing cavity of the guide vane, to obtain the influence range of the guide vane size on the guide vane angle of attack characteristics and flow loss, and to form the design envelope of the guide vane.

3. The compressor guide vane design method according to claim 1, characterized in that: In step S2, the steps of determining the guide vane anti-icing area and the anti-icing hot gas flow are as follows: S21: Obtain typical anti-icing requirement operating conditions within the engine operating envelope. Simultaneously, referencing the guide vane's angle of attack characteristics, perform guide vane ice accumulation analysis to determine the areas where the guide vanes require anti-icing. S22: Based on the prevailing operating conditions of the compressor guide vanes, the anti-icing bleed air status, and the distribution of the guide vanes on the windward side, the anti-icing demand analysis method for the inlet guide vanes is applied to determine the anti-icing hot gas flow rate for the guide vanes.

4. The compressor guide vane design method according to claim 1, wherein: In step S3, the matching analysis method between the hot gas flow rate and the inner cavity structure is: By constructing a flow network in the guide vane cavity and applying the matching analysis method of internal flow resistance and flow rate, the air inlet, internal flow resistance distribution, outflow area of ​​the exhaust window and the minimum throttling area under a given hot gas flow rate are determined.

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