A Design Method for the Supercharging System of an Aero-Piston Two-Stroke Engine

Abstract

The present invention discloses a design method for a supercharging system of an aviation piston two-stroke engine, belonging to the technical field of the design of a supercharging system for an aviation piston two-stroke engine. The method includes: determining the basic parameters and performance enhancement target parameters of the aviation piston two-stroke engine; initially designing the selection of the supercharger and the structural parameters of the resonance pipe; determining the common operating condition parameters of the aviation piston two-stroke engine and the usage weighting values for each operating condition; optimizing the structural parameters of the resonance pipe through a genetic algorithm and determining the control target parameters; machining and assembling the supercharging system for the aviation piston two-stroke engine according to the supercharger and the optimized resonance pipe, and conducting test verification. The method is a design method for a supercharging system of an aviation piston two-stroke engine that is applicable to aircraft with high ceiling, high maximum level flight speed, and long endurance, and takes into account high comprehensive performance under all operating conditions, short design cycle, and low prototyping cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of the design of supercharging systems for aviation piston two-stroke engines, and relates to a design method for a supercharging system for an aviation piston two-stroke engine. Background Art

[0002] Facing the application requirements of multiple scenarios and multiple functions, the requirements of unmanned aerial vehicles (UAVs) for high ceiling, high maximum level flight speed, and long endurance are increasing day by day. With the increase in the altitude of the takeoff site and the flight altitude, affected by the decrease in environmental pressure, natural aspiration engines have problems such as a decrease in intake pressure, a significant attenuation of power, and poor high-altitude power performance, seriously affecting the performance of UAVs such as ceiling, maximum level flight speed, and endurance. Applying a supercharging system can effectively increase the intake pressure of an aviation piston two-stroke engine, restore its high-altitude power, and improve its power performance and economy.

[0003] Existing design methods for supercharging systems of aviation piston two-stroke engines have various deficiencies and defects. The selection of superchargers and the design of the structural dimensions of resonance pipes lack performance optimization calculations based on multiple operating conditions of the engine, and are usually designed for individual conditions based on work experience. The supercharging system designed by this method has a long design cycle, high trial production cost, and a large amount of test and trial work, and it is difficult to achieve the optimal design of multi-objective parameters of power performance and economy of an aviation piston two-stroke engine under all operating conditions. Adopting a scientific and efficient supercharging system design method to enable an aviation piston two-stroke engine to have high comprehensive performance under all conditions while shortening the design cycle, reducing the trial production cost, and reducing the amount of test and trial work is an important problem that urgently needs to be solved by R & D designers. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a supercharging system design method that determines the multi-parameter optimal design of the supercharging system by combining a genetic algorithm with the basic theoretical calculation of an aviation piston two-stroke engine supercharging system, and improves the comprehensive performance of the aviation piston two-stroke engine. This method can avoid the blindness and singularity of traditional empirical design, shorten the R & D cycle, reduce the trial production cost, reduce the amount of test and trial work, and improve the design efficiency.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A design method for a supercharging system of an aviation piston two-stroke engine, characterized by comprising the following steps:

[0007] Step 1: Determine the basic parameters and performance enhancement target parameters of the aviation piston two-stroke engine;

[0008] Step 2: According to the basic parameters and performance optimization target parameters of the aviation piston two-stroke engine, conduct preliminary design of the selection of superchargers and the structural parameters of resonance pipes;

[0009] Step 3: Determine the common operating condition parameters of the aviation piston two-stroke engine and the usage weighting values for each operating condition;

[0010] Step 4: Optimize the structural parameters of the resonance tube through the genetic algorithm and determine the control target parameters of the aviation piston two-stroke engine;

[0011] Step 5: Process and assemble the supercharging system for the aviation piston two-stroke engine according to the supercharger and the optimized resonance tube, and conduct test verification.

[0012] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 1, the basic parameters are the structural and performance parameters of the aviation piston two-stroke engine when the supercharging system is not assembled, specifically including: the displacement V of the engine, the intake and exhaust phases, the maximum power (kW) P of the aviation piston two-stroke engine when the supercharging system is not assembled max and the intake air flow rate (kg / h) Q at this time air,max .

[0013] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 1, the performance optimization target parameters are the target performance parameters to be optimized for the aviation piston two-stroke engine, specifically including: the target maximum power (kW) P' of the engine after assembling the supercharging system max and the target maximum intake air pressure p' of the engine max .

[0014] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 2, the selection of the supercharger and the preliminary design of the structural parameters of the resonance tube specifically include:

[0015] Estimate the maximum compressed air flow rate Q' and the maximum pressure ratio π required to be provided by the supercharger according to the basic parameters and the performance optimization target parameters of the aviation piston two-stroke engine air,max and the maximum pressure ratio π L,max , where

[0016] Q' air,max = Q air,max ·P' max / P max

[0017] π L,max = Q' air,max / Q air,max ;

[0018] Select a supercharger whose performance meets the requirements of the π L,max , Q' air,max and p' max requirements;

[0019] According to the basic parameters of an aviation piston two-stroke engine, preliminarily design the structural parameters of the resonance tube so that the phase of the exhaust pressure wave excited by the resonance tube is consistent with the intake and exhaust phases of the engine.

[0020] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, the structural parameters of the resonance tube include: the total length L of the resonance tube, the diameter D of the inlet section of the resonance tube in and the length L in 、the expansion angle θ of the expansion section of the resonance tube dif and the length L dif 、the diameter D of the resonance section of the resonance tube res and the length L res 、the contraction angle θ of the contraction section of the resonance tube red and the length L red and the diameter D of the outlet section of the resonance tube out and the length L out .

[0021] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in step 3, the common operating condition parameters are the rotational speeds N i 、powers P i 、specific fuel consumption rates b e,i of the aviation piston two-stroke engine under n common operating conditions; the usage weighting values a i for each operating condition are used to characterize the average operating frequency of the n common operating conditions during one usage cycle of the aviation piston two-stroke engine. Among them, i = 1, 2, 3, …, n, representing the i-th common operating condition.

[0022] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in step 4, optimizing the structural parameters of the resonance tube by the genetic algorithm specifically includes:

[0023] Step 41: Determine the resonance tube structure optimization parameter set and the engine and supercharging system control parameter set;

[0024] Step 42: Perform bit string encoding on the resonance tube structure optimization parameter set and the engine and supercharging system control parameter set, and respectively generate initial populations according to the selection of the supercharger and the preliminary design results of the structural parameters of the resonance tube: the first bit string population and the second bit string population;

[0025] Step 43: According to the population size, crossover probability, and mutation probability respectively, perform replication, crossover, and mutation operations on the first bit string population and the second bit string population in sequence, and select those that meet N i and P i under each operating condition, and the weighted value b of the specific fuel consumption rate under all operating conditions e,aThe lowest first-string population individual and the second-string population individual are selected, and the genetic algebra is used as the termination condition for the single-round genetic algorithm calculation, and b is output. e,a The optimal solution and the parameter values of the first-string population and the second-string population under this condition are output. Among them, b e,a = Σa i ·b e,i (i = 1, 2, 3, …, n);

[0026] Step 44: If in the calculation of this round of genetic algorithm, the reduction rate of the output b e,a optimal solution compared to b of the initial population e,a is less than or equal to 1%, it is considered that b e,a converges to this optimal solution, and the parameter values of the first-string population output are used as the optimized resonance tube structure parameters, and the parameter values of the second-string population output are used as the control target parameters of the engine; otherwise, using the parameter values of the first-string population and the second-string population output in the calculation of this round of genetic algorithm as the initial values, the next round of genetic algorithm calculation is carried out.

[0027] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 41, the resonance tube structure optimization parameter set includes: D in , θ dif , D res , L res , θ red , D out .

[0028] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 41, the engine and supercharging system control parameter set includes the engine throttle opening α thr,i and the supercharger nozzle ring opening α VGT,i under n common operating conditions of the engine, i = 1, 2, 3, …, n, representing the i-th common operating condition.

[0029] For the design method of the supercharging system of the aviation piston two-stroke engine as described above, further, in the step 43, the population size is not less than 50; the crossover probability value is 0.5 - 0.8; the mutation probability value is 0.001 - 0.01; the genetic algebra is not less than 25.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] ⑴ The present invention provides a design method for a supercharging system of an aviation piston two-stroke engine. This design method realizes the scientific and efficient design of the supercharging system of the aviation piston two-stroke engine according to the steps of determining the performance enhancement target, preliminary design of the supercharging system, determining the common operating conditions of the engine, optimizing the design by genetic algorithm, and experimental verification. It can effectively avoid the blindness and singularity of the traditional empirical design method, shorten the R & D cycle of the supercharging system, reduce the prototype trial production cost, reduce the amount and cost of test trials, and improve the design efficiency of the supercharging system.

[0032] ⑵ The operation steps of this design method have strong universality and can provide a scientific and efficient supercharging system design scheme for aviation piston two-stroke engines with different models, different supercharging power enhancement requirements, and different common operating condition ranges.

[0033] ⑶ The most significant advantage of this design method is that it optimizes and matches the structure parameters of the resonance pipe of the supercharging system and the engine control target parameters through the genetic algorithm, realizes the significance analysis of the coupling effect of the resonance pipe structure parameters and the engine and supercharger control parameters on the comprehensive performance of the engine, and then scientifically and efficiently gives the best supercharging system design scheme and corresponding control strategy under the full operating conditions of the engine. After the aviation piston two-stroke engine is equipped with the designed supercharging system and applies the corresponding control strategy, the comprehensive performance improvement under all operating conditions can be obtained. Brief Description of the Drawings

[0034] Figure 1 is the flowchart of the design method for the supercharging system of the aviation piston two-stroke engine of the present invention;

[0035] Figure 2 is the structural schematic diagram of the aviation two-stroke piston engine and its supercharging system of the present invention;

[0036] Figure 3 Schematic diagram of the structure parameters of the resonance pipe in the present invention;

[0037] Figure 4 is the flowchart of the multi-parameter coupling optimization design method for the supercharging system based on the genetic algorithm in the present invention. Detailed Embodiment

[0038] The following further describes the technical solution of the present invention with reference to the drawings and specific embodiments.

[0039] The present invention provides a design method for a supercharging system of an aviation piston two-stroke engine. Through the present invention, the design process of the supercharging system can shorten the R & D cycle, reduce the trial production cost, reduce the amount of test trials, and improve the design efficiency on the premise of ensuring the optimal comprehensive performance of the aviation piston two-stroke engine.

[0040] Such as Figure 1As shown in the figure, according to the design process of the supercharging system design method for an aviation piston two-stroke engine of the present invention, the specific steps are as follows:

[0041] Determine the basic parameters and performance enhancement target parameters of the aviation piston two-stroke engine;

[0042] According to the basic parameters and performance optimization target parameters of the aviation piston two-stroke engine, preliminarily design the selection of the supercharger and the structural parameters of the resonance pipe;

[0043] Determine the common operating condition parameters of the aviation piston two-stroke engine and the usage weighting values of each operating condition;

[0044] Optimize the structural parameters of the resonance pipe through the genetic algorithm and determine the control target parameters of the aviation piston two-stroke engine;

[0045] According to the supercharger and the optimized resonance pipe, process and assemble the supercharging system for the aviation piston two-stroke engine and conduct test verification.

[0046] Preferably, the basic parameters are the structural and performance parameters of the aviation piston two-stroke engine when the supercharging system is not assembled, specifically including: the engine intake and exhaust phases, the specific fuel consumption rate, the intake air flow rate, and the intake air pressure under different rotational speeds and power conditions.

[0047] Preferably, the performance optimization target parameters are the target performance parameters to be optimized for the aviation piston two-stroke engine, specifically including: the maximum power of the engine and the corresponding rotational speed, the intake air flow rate, and the intake air pressure.

[0048] Preferably, the preliminary design of the selection of the supercharger and the structural parameters of the resonance pipe specifically includes:

[0049] According to the basic parameters and performance optimization target parameters of the aviation piston two-stroke engine, estimate the maximum compressor air flow rate Q' air,max and the maximum pressure ratio π L,max , where,

[0050] Q' air,max =Q air,max ·P' max / P max

[0051] π L,max =Q' air,max / Q air,max

[0052] In the formula, P and Q air,max are respectively the maximum power (kW) of the aviation piston two-stroke engine when the supercharging system is not assembled and the intake air flow rate (kg / h) at this time; P' maxThe target maximum power (kW) after performance optimization for the engine equipped with a supercharging system;

[0053] Select a supercharger with performance meeting the requirements of the maximum pressure ratio and the maximum compressor air flow;

[0054] According to the basic parameters of the aviation piston two-stroke engine, preliminarily design the structural parameters of the resonance pipe so that the phase of the exhaust pressure wave excited by the resonance pipe is consistent with the intake and exhaust phases of the engine.

[0055] Among them, the structure of the aviation two-stroke piston engine and its supercharging system is as Figure 2 shown. The high-temperature and high-energy exhaust gas after engine combustion passes through the resonance pipe from the exhaust port to the turbine of the supercharger, and then drives the compressor to operate; the intake air is pressurized by the compressor of the selected supercharger and provides supercharged intake for the aviation two-stroke engine; the intake air volume of the engine is adjusted by the throttle valve, the acting force of the high-temperature and high-energy exhaust gas driving the supercharger turbine is adjusted by the nozzle ring, and the resonance effect of the resonance pipe on the exhaust gas affects the intake and exhaust characteristics of the engine.

[0056] Furthermore, as Figure 3 shown, the structural parameters of the resonance pipe include: the total length L of the resonance pipe, the diameter D in and the length L in of the inlet section of the resonance pipe, the expansion angle θ dif and the length L dif of the expansion section of the resonance pipe, the diameter D res and the length L res of the resonance section of the resonance pipe, the contraction angle θ red and the length L red of the contraction section of the resonance pipe, and the diameter D out and the length L out of the outlet section of the resonance pipe. Among them,

[0057] L dif =(D res -D in ) / (2×tanθ dif )

[0058] L red =(D res -D out ) / (2×tanθ red )

[0059] L in =L out =(L-L dif -L res -L red ) / 2

[0060] Preferably, the common operating condition parameters are the rotational speeds N at n common operating conditions of the aviation piston two-stroke enginei 、Power P i 、Specific fuel consumption rate b e,i ; The usage weighted value a for each working condition i is used to characterize the average operation frequency of the n common working conditions within one usage cycle of the aviation piston two-stroke engine. Wherein, i = 1, 2, 3, …, n, representing the i-th common working condition.

[0061] Preferably, the structural parameters of the resonance tube are optimized by a genetic algorithm, and its optimization process is as Figure 4 shown, specifically including:

[0062] Determine the resonance tube structure optimization parameter set (Z1) and the engine and supercharger system control parameter set (Z2). Among them, Z1 includes: D in 、θ dif 、D res 、L res 、θ red 、D out ; Z2 includes the engine throttle opening α thr,i and the supercharger nozzle ring opening α VGT,i (i = 1, 2, 3, …, n, representing the i-th common working condition);

[0063] Perform bit string encoding on Z1 and Z2, and generate an initial population according to the preliminary design results of the supercharger selection and the resonance tube structure parameters;

[0064] Using the genetic algorithm theory, respectively according to the population size (set according to the hardware conditions of the computing device, usually not less than 50), the crossover probability (usually taking values from 0.5 to 0.8) and the mutation probability (usually taking values from 0.001 to 0.01), perform replication, crossover, and mutation operations on the Z1 bit string population and the Z2 bit string population in sequence, and select the individuals of the Z1 bit string population and the Z2 bit string population that meet N i and P i 、the weighted value b of the specific fuel consumption rate under all working conditions e,a is the lowest, and take the number of genetic generations (set according to the hardware conditions of the computing device, usually not less than 25) as the termination condition for a single round of genetic algorithm calculation, and output the optimal solution of b e,a and the parameter values of Z1 and Z2 under this condition. Among them, b e,a = Σa i ·b e,i (i = 1, 2, 3, …, n);

[0065] If in this round of genetic algorithm calculation, the reduction rate of the optimal solution of b e,a compared with b e,a of the initial population is less than or equal to 1%, then it is considered that b e,aConverge to this optimal solution, and use the parameter values of each output Z1 as the optimized structure parameters of the resonance tube, and use the parameter values of each output Z2 as the target control values of the engine throttle and the supercharger nozzle ring under each working condition; otherwise, use the parameter values of Z1 and Z2 calculated by this round of genetic algorithm as the initial values, and perform the next round of genetic algorithm calculation.

[0066] Finally, in this embodiment, according to the basic parameters and performance enhancement target parameters of the aviation piston two-stroke engine of the supercharging system to be designed, a supercharger that meets the requirements is selected, and the structure parameters of the resonance tube are obtained through genetic algorithm optimization: the total length of the resonance tube L = 1205 mm, the diameter D of the inlet section of the resonance tube in = 62 mm and the length L in = 180 mm, the expansion angle θ of the expansion section of the resonance tube dif = 4.7° and the length L dif = 430 mm, the diameter D of the resonance section of the resonance tube res = 132 mm and the length L res = 140 mm, the contraction angle θ of the contraction section of the resonance tube red = 7.3° and the length L red = 335 mm, and the diameter D of the outlet section of the resonance tube out = 46 mm and the length L out = 120 mm.

[0067] The aviation piston two-stroke engine of this embodiment is tested and verified. The test results show that after the engine is equipped with the supercharging system designed according to the design method of the present invention, its maximum power increases from 58 kW to 76 kW, meeting the design requirements; compared with the preliminary design scheme of the resonance tube structure parameters, after the engine is assembled with the resonance tube structure parameter design scheme optimized by the genetic algorithm, the weighted value b of the specific fuel consumption rate under all working conditions e,a decreases by 23.6%, and the minimum value of the specific fuel consumption rate under all working conditions reaches 280 g / (kW·h).

[0068] The above has introduced in detail a design method for a supercharging system of an aviation piston two-stroke engine provided by an embodiment of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

[0069] As used in the specification and claims, certain terms are used to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not distinguish components by the difference in names, but by the difference in functions of the components. As used throughout the specification and claims, the terms "comprising" and "including" are open-ended terms and should be interpreted as "comprising / including but not limited to". "Substantially" means within an acceptable error range. Those skilled in the art can solve the technical problems within a certain error range and basically achieve the technical effects. The following description in the specification is the preferred embodiment for implementing the present application, but the description is for the purpose of explaining the general principles of the present application and is not intended to limit the scope of the present application. The protection scope of the present application shall be subject to what is defined by the appended claims.

[0070] It should also be noted that the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, such that a commodity or system including a series of elements not only includes those elements but also includes other elements not expressly listed, or also includes elements inherent to such commodity or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the commodity or system including said element.

[0071] It should be understood that the term "and / or" used herein is only a correlative relationship describing associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0072] The above description shows and describes several preferred embodiments of the present application. However, as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the application concept described herein through the above teachings or the technology or knowledge in the relevant field. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present application shall fall within the protection scope of the appended claims of the present application.

Claims

1. A design method for a supercharging system of an aviation piston two-stroke engine, characterized in that, Including the following steps: Step 1: Determine the basic parameters of the aviation piston two-stroke engine and the target parameters for performance optimization; Step 2: According to the basic parameters of the aviation piston two-stroke engine and the target parameters for performance optimization, select and match the supercharger and preliminarily design the structural parameters of the resonance pipe; Step 3: Determine the common operating condition parameters of the aviation piston two-stroke engine and the usage weighting values for each operating condition; Step 4: Optimize the structural parameters of the resonance pipe through the genetic algorithm and determine the control target parameters of the aviation piston two-stroke engine; Step 5: According to the supercharger and the optimized resonance pipe, machine and assemble the supercharging system for the aviation piston two-stroke engine and conduct test verification, wherein, in the said Step 4, the optimizing the structural parameters of the resonance pipe through the genetic algorithm specifically includes: Step 41: Determine the resonance tube structure optimization parameter set and the engine and supercharging system control parameter set; wherein the resonance tube structure optimization parameter set includes: the diameter D of the resonance tube inlet section in , the expansion angle θ of the expansion section of the resonance tube dif , the diameter D of the resonance section of the resonance tube res and length L res , the contraction angle θ of the contraction section of the resonance tube red And the diameter D of the resonance tube outlet section out ; The engine and supercharging system control parameter set includes the engine throttle opening α under n common engine operating conditions thr,i and supercharger nozzle ring opening α VGT,i , i=1,2,3,…,n, indicating the i-th common working condition; Step 42: Perform bit string encoding on the resonance pipe structure optimization parameter set and the engine and supercharging system control parameter set, and respectively generate the initial populations: the first bit string population and the second bit string population according to the result of the selection and matching of the supercharger and the preliminary design of the structural parameters of the resonance pipe; Step 43: According to the population size, crossover probability, and mutation probability respectively, perform replication, crossover, and mutation operations on the first-bit string population and the second-bit string population in sequence, and select the individual of the first-bit string population and the individual of the second-bit string population with the lowest weighted value of the specific fuel consumption rate under each working condition that meet N i and P i , the weighted value b e,a of the specific fuel consumption rate under all working conditions. Take the number of generations as the termination condition for a single-round genetic algorithm calculation, and output the optimal solution of b e,a and the parameter values of the first-bit string population and the second-bit string population under this condition. Among them, b e,a =Σa i ·b e,i , where b e,i is the specific fuel consumption rate under n common working conditions of the aviation piston two-stroke engine; a i is the usage weighted value of each working condition, which is used to characterize the average operation frequency of the n common working conditions in a usage cycle of the aviation piston two-stroke engine; among them, the population size is not less than 50; the crossover probability ranges from 0.5 to 0.8; the mutation probability ranges from 0.001 to 0.01; the number of generations is not less than 25; Step 44: If in the current round of genetic algorithm calculation, the reduction rate of the b e,a optimal solution compared to the b e,a of the initial population is less than or equal to 1%, then it is considered that b e,a converges to this optimal solution, and the parameter values of each first-bit string population output are used as the optimized structure parameters of the resonator tube, and the parameter values of each second-bit string population output are used as the control target parameters of the engine; otherwise, using the parameter values of the first-bit string population and the second-bit string population output in the current round of genetic algorithm calculation as the initial values, perform the next round of genetic algorithm calculation.

2. The design method of the supercharging system for an aviation piston two-stroke engine according to claim 1, wherein In the said step 1, the basic parameters are the structural and performance parameters of the aviation piston two-stroke engine without a supercharging system, specifically including: the displacement V of the engine, the intake and exhaust phases, and the maximum power P of the aviation piston two-stroke engine without a supercharging system max and the intake air flow rate Q at this time air,max .

3. The design method of the supercharging system for an aviation piston two-stroke engine according to claim 2, characterized in that, In the step 1, the performance optimization target parameter is the target performance parameter to be optimized for the aviation piston two-stroke engine, specifically including: the target maximum power P' of the engine after assembling the supercharging system max and the target maximum intake pressure p' of the engine max .

4. The design method of the supercharging system for an aviation piston two-stroke engine according to claim 3, characterized in that, In the said Step 2, the selection and matching of the supercharger and the preliminary design of the structural parameters of the resonance pipe specifically include: Estimate the maximum compressor air flow rate Q' air,max and the maximum pressure ratio π L,max required to be provided by the supercharger according to the basic parameters and performance optimization target parameters of the aviation piston two-stroke engine, where Q' air,max = Q air,max · P' max / P max π L,max = Q' air,max / Q air,max ; Select a supercharger whose performance meets the requirements of the said π L,max , Q' air,max and p' max ; According to the basic parameters of the aviation piston two-stroke engine, preliminarily design the structural parameters of the resonance pipe so that the phase of the exhaust pressure wave excited by the resonance pipe is consistent with the intake and exhaust phases of the engine.

5. The design method of the supercharging system for an aviation piston two-stroke engine according to claim 4, characterized in that, The structural parameters of the resonance tube include: the total length L of the resonance tube, the diameter D of the inlet section of the resonance tube in and the length L in , the expansion angle θ of the expansion section of the resonance tube dif and the length L dif , the diameter D of the resonance section of the resonance tube res and the length L res , the contraction angle θ of the contraction section of the resonance tube red and the length L red and the diameter D of the outlet section of the resonance tube out and the length L out .

6. The design method of the supercharging system for an aviation piston two-stroke engine according to claim 1, characterized in that, In the step 3, the common operating parameters are the rotational speeds N at n common operating conditions of the aviation piston two-stroke engine i , the power P i , the specific fuel consumption rate b e,i ; the usage weighting value a for each operating condition i is used to characterize the average operating frequency of the n common operating conditions within one usage cycle of the aviation piston two-stroke engine, where i = 1, 2, 3, …, n represents the i-th common operating condition.

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