Method for improving aero-engine performance based on pressure self-adaptive valve

Abstract

The invention provides a method for improving the performance of an aero-engine based on pressure self-adaptive valves, and relates to the technical field of aero-engines, and the method comprises the following steps: acquiring working parameters of the aero-engine, and determining the number of the pressure self-adaptive valves and the flow area of through holes based on the working parameters of the aero-engine; and the structure and size parameters of the pressure self-adaptive valve are determined, and the pressure self-adaptive valve is arranged in an annular cavity in front of an aero-engine turbine. A certain number of self-adaptive pressure regulation and control valve structures are arranged in the annular cavity in front of the turbine of the aero-engine, specific 1-0-1 bleed air flow control is achieved through valve regulation and control, and on the premise that the aero-engine can stably work in all operation stages through the bleed air flow control, high-pressure cold air waste is reduced, and the service life of the aero-engine is prolonged. And the aero-engine performance is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engines, and in particular to a method for improving aero-engine performance based on a pressure adaptive valve. Background Art

[0002] Currently, aircraft engine turbine blades require high-pressure cooling air from the compressor. As compressor pressure ratios continue to increase, the temperature of the high-pressure cooling air also rises, resulting in a decrease in heat sinking and poor cooling effectiveness. Meeting the cooling needs of the turbine blades requires a higher cooling airflow rate, which results in significant waste of high-pressure air. For example, for an operating temperature of 1900K before the turbine, using advanced film cooling technology requires extracting at least 15% of the air from the compressor for turbine cooling. However, the mainstream air flow directly affects turbine performance and, consequently, aircraft engine performance. Therefore, properly regulating the bleed air flow rate during aircraft engine operation is crucial for improving aircraft engine performance. Adjusting the bleed air flow rate and the mainstream air flow rate based on actual needs can be done by appropriately reducing the bleed air ratio during cruise phases to avoid cooling air waste. Reusing the saved high-pressure cooling air for engine power generation ensures proper component cooling while improving thermal efficiency, optimizing fuel consumption, and significantly improving engine performance.

[0003] The operation process of an aircraft includes the starting stage, cruising stage, extreme state and other stages. At the same time, the aircraft engine also corresponds to different states, and each state has different requirements for the flow rate of each working fluid inside it.

[0004] Therefore, in order to reasonably adjust the bleed air flow and further improve the performance of the aircraft engine, an adaptive pressure control valve is arranged in the annular cavity in front of the aircraft engine turbine. The valve adaptively adjusts the opening and closing of the interface to meet the bleed air flow requirements at each stage, ensuring that the engine can work normally in each stage and saving high-pressure cooling air to a certain extent. The extra high-pressure cooling air is used for turbine work, further improving the engine performance.

[0005] Currently available adaptive control valves mostly rely on sensors to collect valve opening information, combine it with specific pressure and flow operating conditions, set a control program, and then use an electronically controlled actuator to control the valve opening, thus achieving adaptive control of the valve. However, the internal environment of aircraft engines is extremely harsh. Valves operate under high pressure, high temperature, and high load for long periods of time. Limited installation space and harsh environmental conditions all pose numerous challenges to the application of adaptive valves in aircraft engines. Existing electronically controlled valve autonomous adjustment structures not only require the installation of sensors and corresponding control mechanisms, but also consider whether the material properties of the sensors and control mechanisms can adapt to the environmental conditions. This requires additional protective measures and increases the control burden. Therefore, existing electronically controlled adaptive valve technology is difficult to meet the demanding requirements of aircraft engines.

[0006] The above problems can be avoided by using a traditional adjustable valve that changes the interception area with the working fluid pressure. The bleed air flow demand of an aircraft engine at each stage is not a simple one-way change with the working fluid pressure. From the startup phase to the cruise phase, the pressure continues to increase, but the valve flow area must always be maximized, and the overall bleed air flow must be maximized to ensure safety. Then, during the cruise phase, the valve flow area is required to be always zero, and the overall bleed air flow must be minimized to ensure economy. When the pressure continues to increase beyond the cruise state limit, the maximum flow area is restored, and the maximum flow is maintained until the limit state to ensure safety. The overall state requires that the interception area is 0 only during the cruise phase (when the working fluid pressure is between P1 and P2). When the pressure is less than P1 and greater than P2, the interception area remains approximately the same, at the maximum interception area. As the working fluid pressure increases, the interception area changes from maximum to 0 and then back to maximum, and the interception area and the working fluid flow rate have an approximate 1-0-1 change.

[0007] Therefore, it is necessary to design a method based on pressure adaptive valve to improve the performance of aircraft engines. Summary of the Invention

[0008] In order to overcome the deficiencies of the prior art, an object of the present invention is to provide a method for improving aircraft engine performance based on a pressure adaptive valve.

[0009] To achieve the above object, the present invention provides the following solutions:

[0010] The present invention provides a method for improving aircraft engine performance based on a pressure adaptive valve, comprising:

[0011] Step 1: Obtain aircraft engine operating parameters;

[0012] Step 2: Determine the number of pressure adaptive valves and the through-hole flow area based on the aircraft engine operating parameters;

[0013] Step 3: Determine the structure and size parameters of the pressure adaptive valve;

[0014] Step 4: Arrange the pressure adaptive valve inside the annular cavity in front of the turbine of the aircraft engine.

[0015] Preferably, in step 1, the aircraft engine operating parameters are obtained, specifically:

[0016] Obtain the cross-sectional area S, inner diameter r1, outer diameter r2 of the annular cavity in front of the aircraft engine turbine, and the maximum mass flow rate and minimum mass flow rate required for the operation of the aircraft engine, and convert the maximum mass flow rate and minimum mass flow rate required for the operation of the aircraft engine into the corresponding flow area S MAX and S MIN .

[0017] Preferably, in step 2, the number of pressure adaptive valves and the through-hole flow area are determined based on the aircraft engine operating parameters, specifically:

[0018] Define the valve housing cross-sectional area s1, radius r, and maximum flow area s2 of the valve through hole. The optimal values ​​for the number of valves and the flow area of ​​the valve through hole are determined within the following ranges, ensuring both the maximum and minimum bleed air flow requirements and the valves can be accommodated in the annular cavity:

[0019]

[0020] Where n is the number of valves.

[0021] Preferably, the structure of the pressure adaptive valve specifically includes: a shell, a valve core, a diverter ring and a pressure spring. The diverter ring is fixedly arranged on the upper interior of the shell. The diverter ring and the shell form a two-layer structure of an inner ring and an outer ring, wherein the inner ring is used for diversion and the outer ring is used for fluid circulation after diversion. The valve core is arranged below the diverter ring, and a stepped groove is arranged inside the shell for fixing the sliding path of the valve core. The pressure spring is arranged between the valve core and the diverter ring.

[0022] Preferably, the valve core structure is a two-layer thin-walled cylinder, wherein the outer circumference of the upper wall cylinder is slightly smaller, and the whole is stepped, which is used to facilitate nesting and sliding under pressure. The lower structure of the valve core is provided with a circle of 5 first through holes around the circumference, and its height is h, which is used for airflow.

[0023] Preferably, two fan-shaped extensions are provided on the upper part of the diverter ring for fixed connection with the shell, and a circle of 5 second through holes is provided around the circumference at the bottom of the diverter ring, and 5 third through holes are provided at a height of 1 / 2h below the diverter ring, separated by through holes, and two layers of fourth through holes with a height of 1 / 2h are provided around the circumference in the middle of the diverter ring, with 10 through holes in each layer and a distance of 1 / 2h between the two layers.

[0024] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0025] The present invention provides a method for improving aircraft engine performance using pressure-adaptive valves. The method comprises obtaining aircraft engine operating parameters, determining the number of pressure-adaptive valves and the flow area of ​​through-holes based on the aircraft engine operating parameters, determining the structure and dimensional parameters of the pressure-adaptive valves, and arranging the pressure-adaptive valves within the annular cavity preceding the aircraft engine turbine. The present invention employs a specific 1-0-1 bleed air flow control mechanism by disposing a predetermined number of adaptive pressure-regulating valve structures within the annular cavity preceding the aircraft engine turbine. This bleed air flow control mechanism ensures stable operation of the aircraft engine at all stages of operation while reducing high-pressure cooling air waste and further improving aircraft engine performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a flow chart of a method for improving aircraft engine performance based on a pressure adaptive valve according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram showing the area of ​​each surface of the pressure adaptive control valve;

[0029] Figure 3 The pressure-adaptive control valve structure provided by this technical invention and its distribution diagram in the turbine front ring cavity;

[0030] Figure 4 Schematic diagram of the structure inside the pressure adaptive valve housing;

[0031] Figure 5 This is a schematic diagram of the disassembled structure of the pressure adaptive regulating valve;

[0032] Figure 6 This is the working principle diagram of the pressure adaptive control valve;

[0033] Figure 7 Schematic diagram of the internal structure of the pressure adaptive control valve.

[0034] Figure numerals: 1. housing; 2. diverter ring; 3. valve core; 4. pressure spring; 5. first through hole structure; 6. second through hole structure; 7. third through hole structure; 8. fourth through hole structure. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] The purpose of the present invention is to provide a method for improving aircraft engine performance based on pressure adaptive valves. By arranging a certain number of adaptive pressure control valve structures in the annular cavity in front of the aircraft engine turbine, a specific 1-0-1 bleed air flow control is achieved through valve regulation. This bleed air flow control can ensure that the aircraft engine operates stably in all stages of operation, reduce the waste of high-pressure cooling air, and further improve the performance of the aircraft engine.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] like Figure 1 As shown, the present invention provides a method for improving aircraft engine performance based on a pressure adaptive valve, comprising:

[0039] Step 1: Obtain aircraft engine operating parameters;

[0040] Step 2: Determine the number of pressure adaptive valves and the through-hole flow area based on the aircraft engine operating parameters;

[0041] Step 3: Determine the structure and size parameters of the pressure adaptive valve;

[0042] Step 4: Arrange the pressure adaptive valve inside the annular cavity in front of the turbine of the aircraft engine.

[0043] In step 1, the aircraft engine operating parameters are obtained, specifically:

[0044] Obtain the cross-sectional area S, inner diameter r1 and outer diameter r2 of the annular cavity in front of the aircraft engine turbine, as well as the maximum and minimum mass flow rates required for aircraft engine operation, and convert the maximum and minimum mass flow rates required for aircraft engine operation into corresponding flow areas SMAX and SMIN.

[0045] In step 2, the number of pressure adaptive valves and the through-hole flow area are determined based on the aircraft engine operating parameters, specifically:

[0046] Define the valve housing cross-sectional area s1, radius r, and maximum flow area s2 of the valve through hole. The optimal values ​​for the number of valves and the flow area of ​​the valve through hole are determined within the following ranges, ensuring both the maximum and minimum bleed air flow requirements and the valves can be accommodated in the annular cavity:

[0047]

[0048] Where n is the number of valves.

[0049] In step 3, the structure and size parameters of the pressure adaptive valve are determined, specifically:

[0050] The valve core structure is designed in a multi-layered stepped shape to reduce overall weight. Detailed valve dimensions are determined based on the surface pressure and area of ​​each step, the spring's elastic coefficient, the relative position of the valve core, and the valve through-hole area, corresponding to each engine state (i.e., the pressure range at each stage). This ensures that the valve core and diverter ring can maintain their predetermined positions under all engine operating conditions, meeting the specified bleed air flow control requirements.

[0051] like Figure 2 As shown, the area of ​​each surface of the valve core is S1, S2, S3, S4, and S5, respectively. The pressure acting on each surface is p1, p2, p3, p4, and p5. The inner diameter of the valve core is R, the elastic coefficient of the spring is k, the compression of the spring in the initial state is x1, the compression of the spring in the cruising state is x2, and the compression of the spring in the limit state is x3.

[0052] At the starting position: p1·S1+p3S3+p4S4-p2(S2-S3)-p5S5=kx1

[0053] In cruising position: p1·S1+p3S3+p4S4-p2S2-p5S5=kx2

[0054] At the extreme position: p1·S1+p4S4-p2S2-p5S5=kx3

[0055] By calculating the parameters of the starting position and the cruise position, we can get x2-x1=2h. From the through hole h, we can know that the maximum flow area of ​​the through hole is s2, which means the valve radius and the corresponding length of the valve core in the cruise stage is l, l=x3-x2-3h;

[0056] Designing and placing valves according to the above parameters can achieve the established 1-0-1 bleed air flow control, avoid waste of cold air, and save high-pressure cold air for turbine work to improve engine performance;

[0057] like Figure 2-7 As shown, based on this, the present invention provides a structure of the pressure adaptive valve specifically including: a shell 1, a valve core 3, a diverter ring 2 and a pressure spring 4, the diverter ring 2 is fixedly arranged on the upper interior of the shell, the diverter ring 2 and the shell 1 form a two-layer structure of an inner ring and an outer ring, wherein the inner ring is used for diversion, and the outer ring is used for fluid circulation after diversion, the valve core 3 is arranged below the diverter ring 2, and a stepped groove is arranged inside the shell 1 for fixing the valve core sliding path, and the pressure spring 4 is arranged between the valve core 3 and the diverter ring 2.

[0058] The valve core 3 is a structure of two thin-walled cylinders, wherein the outer circumference of the upper wall cylinder is slightly smaller, and the whole is stepped, which is used to facilitate nesting and sliding under pressure. The lower structure of the valve core is provided with a circle of 5 first through holes 5 around the circumference. The cross section of the through hole is fan-shaped with a central angle of 30° and a height of h for air flow.

[0059] Two fan-shaped extensions are provided on the upper part of the diverter ring for fixed connection with the shell. A total of five second through holes 6 are provided around the circumference at the bottom of the diverter ring, and five third through holes 7 are provided at a height of 1 / 2h below the diverter ring. Two layers of fourth through holes 8 with a height of 1 / 2h are provided around the circumference in the middle of the diverter ring, with 10 through holes in each layer and a distance of 1 / 2h between the two layers.

[0060] The pressure spring 4 is located between the diverter ring 2 and the valve core 3. The valve core 3 slides under pressure, and the pressure spring 4 is compressed and restored within a certain range. The sliding distance of the valve core in the upper half of the diverter ring and the height of the through hole are calculated based on the actual pressure in each stage and the elastic modulus of the pressure spring 4. The relative position of the diverter ring 2 and the valve core 3 in each stage under the action of pressure is determined. In the initial stage, the valve core 3 is in the initial position, and the upper surface of the first through hole 5 and the upper surface of the second through hole 6 are at the same height. When the pressure reaches P1, the sliding position of the valve core must ensure that the lower surface of the first through hole 5 and the upper surface of the third through hole 7 are at the same height. When the pressure reaches P2, the upper surface of the first through hole 5 and the lower surface of the third through hole 8 are at the same height. When the pressure is between P1 and P2, it is considered the cruising stage. It is necessary to ensure that the first through hole 5 is completely blocked by the diverter ring wall in this stage, and the valve flow area is 0. In the remaining stages, no matter what the pressure is, the valve flow area remains consistent with the initial valve flow area to maintain the maximum flow area;

[0061] The relative position of the valve core diverter ring and the length h are determined by the pressure difference of the valve core at each stage and the elastic coefficient of the spring, which in turn affects the overall length L of the valve;

[0062] The method is to achieve approximately 1-0-1 flow control through a pressure-regulating valve structure set inside the annular cavity. The valve achieves autonomous control through changes in fluid pressure. As the pressure increases, the flow control is divided into three stages. During the valve core stationary stage, the valve maintains a maximum flow area. As the pressure continues to increase, the valve core begins to slide upward. However, the valve core and the inner and outer through-holes of the diverter ring are staggered to always maintain the maximum flow area of ​​the valve. As the pressure continues to increase, the through-holes of the valve core and the diverter ring are closed, and the valve is completely closed. As the pressure continues to increase and exceeds a certain limit, the valve core is pressed to the limit position, and the pressure spring is compressed to the maximum. At this time, the flow area is half of the area of ​​10 small through-holes, which can still ensure the same maximum flow area as the initial stage, achieving 1-0-1 flow control. This flow control effect can meet the high-pressure cooling air bleed demand of the aircraft engine in various stages of operation. During the cruise stage, the engine bleed air demand is reduced, and the extra high-pressure cooling air is used to perform work in the aircraft engine turbine, further improving the performance of the aircraft engine.

[0063] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0064] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A method for improving aircraft engine performance based on a pressure adaptive valve, characterized in that: include: Step 1: Obtain aircraft engine operating parameters; Step 2: Determine the number of pressure adaptive valves and the through-hole flow area based on the aircraft engine operating parameters; Step 3: Determine the structure and size parameters of the pressure adaptive valve; Step 4: Arrange the pressure adaptive valve inside the annular cavity in front of the turbine of the aircraft engine.

2. The method according to claim 1, characterized in that In step 1, the aircraft engine operating parameters are obtained, specifically: Obtain the cross-sectional area S, inner diameter r1, outer diameter r2 of the annular cavity in front of the aircraft engine turbine, and the maximum mass flow rate and minimum mass flow rate required for the operation of the aircraft engine, and convert the maximum mass flow rate and minimum mass flow rate required for the operation of the aircraft engine into the corresponding flow area S MAX and S MIN .

3. The method according to claim 2, characterized in that In step 2, the number of pressure adaptive valves and the through-hole flow area are determined based on the aircraft engine operating parameters, specifically: Define the valve housing cross-sectional area s1, radius r, and maximum flow area s2 of the valve through hole. The optimal values ​​for the number of valves and the flow area of ​​the valve through hole are determined within the following ranges, ensuring both the maximum and minimum bleed air flow requirements and the valves can be accommodated in the annular cavity: Where n is the number of valves.

4. The method according to claim 3, characterized in that The structure of the pressure adaptive valve specifically includes: a shell, a valve core, a diverter ring and a pressure spring. The diverter ring is fixedly arranged on the upper interior of the shell. The diverter ring and the shell form a two-layer structure of an inner ring and an outer ring, wherein the inner ring is used for diversion and the outer ring is used for fluid circulation after diversion. The valve core is arranged below the diverter ring, and a stepped groove is arranged inside the shell for fixing the sliding path of the valve core. The pressure spring is arranged between the valve core and the diverter ring.

5. The method according to claim 4, characterized in that The valve core structure is a two-layer thin-walled cylinder, wherein the outer circumference of the upper wall cylinder is slightly smaller, and the whole is stepped, which is used to facilitate nesting and sliding under pressure. The lower structure of the valve core is provided with a circle of 5 first through holes around the circumference, and its height is h, which is used for airflow.

6. The method according to claim 5, characterized in that Two fan-shaped extensions are provided on the upper part of the diverter ring for fixed connection with the shell. A circle of five second through holes is provided around the circumference at the bottom of the diverter ring, and five third through holes are provided at a height of 1 / 2h below the diverter ring, separated by through holes. Two layers of fourth through holes with a height of 1 / 2h are provided around the circumference in the middle of the diverter ring, with 10 through holes in each layer and a distance of 1 / 2h between the two layers.

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