A comprehensive design method for infrared stealth and aerodynamic and thermal performance of aircraft engines

Abstract

This application belongs to the field of aero-engines, and particularly relates to a method for the comprehensive design of infrared stealth and aero-thermodynamic performance of an aero-engine. The method comprises: determining comprehensive optimization constraints and comprehensive optimization objectives for the infrared stealth and aero-thermodynamic performance of the engine; determining coupling variables that affect the infrared stealth and aero-thermodynamic performance of the engine, selecting engine aero-thermodynamic cycle parameters from the coupling variables, and determining multiple sets of different engine aero-thermodynamic cycle parameters based on the variation range of the coupling variables; calculating engine performance parameters and the forward and backward infrared radiation intensity of the engine based on the multiple sets of different engine aero-thermodynamic cycle parameters; and, when the engine performance parameters meet the requirements, determining the values of the engine aero-thermodynamic cycle parameters based on the principle of minimizing the forward and backward infrared radiation intensity of the engine, thereby completing the comprehensive design of the infrared stealth and aero-thermodynamic performance of the engine.

Description

Technical Field

[0001] The present application relates to the field of aero-engines, and in particular to a method for integrated design of infrared stealth and aerodynamic and thermal performance of an aero-engine. Background Art

[0002] There are many design variables for coupling the infrared stealth and aerodynamic and thermal performance of aircraft engines. These variables are closely related and have significant contradictions. The stealth design makes the aircraft engine flow profile complex and the cooling air volume large, resulting in large thrust loss.

[0003] Traditional design methods first determine the engine's aerodynamic and thermodynamic cycle parameters and structural parameters, targeting performance indicators such as thrust and fuel consumption. Based on this, stealth design is then carried out, enhancing stealth capabilities through measures such as increasing the external-to-internal pressure ratio, increasing the amount of cooling air to visible components, and adding shielding structures. However, these measures will change the engine's aerodynamic and thermodynamic cycle parameters. For example, increasing the amount of cooling air will increase mixing losses between the cooling air and the main flow, and adding shielding structures will increase flow losses in the main flow path, resulting in a significant decrease in performance indicators such as thrust. Therefore, traditional design methods lack a comprehensive analysis and consideration of the impact of coupled design variables on the engine's infrared stealth and aerodynamic and thermodynamic performance, making it impossible to achieve a comprehensive optimization design of the engine's infrared stealth and aerodynamic and thermodynamic performance.

[0004] Therefore, there is an urgent need for a technical solution to overcome or alleviate at least one of the above-mentioned defects of the prior art. Summary of the Invention

[0005] The purpose of this application is to provide a comprehensive design method for the infrared stealth and aerodynamic and thermal performance of an aircraft engine to solve at least one problem existing in the prior art.

[0006] The technical solution of this application is:

[0007] A comprehensive design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine, comprising:

[0008] Step 1: Determine the comprehensive optimization constraints and comprehensive optimization objectives of the engine's infrared stealth and aerodynamic thermal performance, wherein the comprehensive optimization constraints are that the engine performance parameters meet the requirements, and the comprehensive optimization objective is that the engine's forward and backward infrared radiation intensity is minimized;

[0009] Step 2: determining coupling variables that affect the infrared stealth and aerodynamic and thermodynamic performance of the engine, selecting engine aerodynamic and thermodynamic cycle parameters from the coupling variables, and determining multiple sets of different engine aerodynamic and thermodynamic cycle parameters based on the variation range of the coupling variables;

[0010] Step 3: Calculating the engine performance parameters and the forward and backward infrared radiation intensity of the engine based on multiple sets of different engine aerodynamic and thermodynamic cycle parameters;

[0011] Step 4: When the engine performance parameters meet the requirements, the values of the engine aerodynamic and thermodynamic cycle parameters are determined based on the principle of minimizing the infrared radiation intensity in the forward and backward directions of the engine, and the comprehensive design of the engine's infrared stealth and aerodynamic and thermodynamic performance is completed.

[0012] In at least one embodiment of the present application, the engine performance parameters include thrust, fuel consumption rate, fan and compressor pressure ratio, fan and compressor surge margin, and turbine inlet temperature.

[0013] In at least one embodiment of the present application, in step 2, determining multiple sets of different engine aerodynamic and thermodynamic cycle parameters according to the variation range of the coupling variable includes:

[0014] determining the variation range of each of the coupling variables based on historical data;

[0015] determining a preset step size for each of the coupling variables;

[0016] According to the preset step size, determining a plurality of values from the variation range of the coupling variable as corresponding values of the engine aerodynamic and thermodynamic cycle parameters;

[0017] The values of the various engine aerodynamic and thermodynamic cycle parameters are combined to obtain multiple groups of different engine aerodynamic and thermodynamic cycle parameters.

[0018] In at least one embodiment of the present application, the engine aerodynamic and thermodynamic cycle parameters include: internal outlet gas flow, internal outlet gas temperature, turbine cooling air flow, turbine cooling air temperature, afterburner cooling air flow, afterburner cooling air temperature, nozzle cooling air flow, nozzle cooling air temperature, nozzle throat area, and nozzle outlet area.

[0019] In at least one embodiment of the present application, in step three, the engine performance parameters are calculated using the overall performance design software Gasturb.

[0020] In at least one embodiment of the present application, in step 3, the process of calculating the forward and backward infrared radiation intensity of the engine includes:

[0021] The average temperature of the turbine solid wall visible from behind is calculated based on the engine aerodynamic and thermodynamic cycle parameters:

[0022] T 涡轮 =f(W6, T6, W 涡轮冷却气 , T 涡轮冷却气 );

[0023] The average temperature of the solid wall of the afterburner chamber visible from behind is calculated based on the aerodynamic and thermodynamic cycle parameters of the engine:

[0024] T 加力燃烧室 =f(W6, T6, W 加力燃烧室冷却气 , T 加力燃烧室冷却气 );

[0025] The average temperature of the solid wall of the rear-view nozzle is calculated based on the engine aerodynamic and thermodynamic cycle parameters:

[0026] T 喷管 =f(W6, T6, W 喷管冷却气 , T 喷管冷却气 );

[0027] Among them, T 涡轮 is the average temperature of the turbine solid wall visible from the rear, T 加力燃烧室 is the average temperature of the solid wall of the afterburner visible from behind, T 喷管 is the average temperature of the solid wall of the rear-view nozzle, W6 is the internal outlet gas flow rate, T6 is the internal outlet gas temperature, W 涡轮冷却气 is the turbine cooling air flow rate, T 涡轮冷却气 is the turbine cooling air temperature, W 加力燃烧室冷却气 is the cooling air flow rate of the afterburner, T 加力燃烧室冷却气 is the afterburner coolant temperature, W 喷管冷却气 is the nozzle cooling air flow rate, T 喷管冷却气 is the nozzle cooling gas temperature;

[0028] Calculate the projected area of the turbine visible region based on the engine aerodynamic and thermodynamic cycle parameters:

[0029] A 涡轮 =A8-πR 2 内锥 ;

[0030] Calculate the projected area of the afterburner visible region based on the engine aerodynamic and thermodynamic cycle parameters:

[0031] A 加力燃烧室 =πR 2 内锥 ;

[0032] The projected area of the nozzle visible region is calculated based on the engine aerodynamic and thermodynamic cycle parameters:

[0033] A 喷管 =A9-A8;

[0034] Among them, A 涡轮 is the projected area of the turbine visible area, A 加力燃烧室 is the projected area of the afterburner visible area, A 喷管 is the projected area of the nozzle visible area, A8 is the nozzle throat area, A9 is the nozzle outlet area, R 内锥is the radius of the cone inside the afterburner;

[0035] Calculate the intensity of infrared radiation generated by the turbine itself:

[0036] IR 涡轮 =ε 涡轮 σT 4 涡轮 A 涡轮 ;

[0037] Calculate the infrared radiation intensity generated by the afterburner itself:

[0038] IR 加力燃烧室 =ε 加力燃烧室 σT 4 加力燃烧室 A 加力燃烧室 ;

[0039] Calculate the infrared radiation intensity generated by the nozzle itself:

[0040] IR 喷管 =ε 喷管 σT 4 喷管 A 喷管 ;

[0041] Among them, IR 涡轮 is the infrared radiation intensity generated by the turbine itself, IR 加力燃烧室 is the infrared radiation intensity generated by the afterburner itself, IR 喷管 is the infrared radiation intensity generated by the nozzle itself, ε 涡轮 is the infrared emissivity of the turbine solid wall, ε 加力燃烧室 is the infrared emissivity of the afterburner solid wall, ε 喷管 is the infrared emissivity of the nozzle solid wall, σ is the Stefan-Boltzmann constant;

[0042] Calculate the infrared radiation intensity from the engine forward and backward:

[0043] IR 发动机 =IR 涡轮 +IR 加力燃烧室 +IR 喷管 ;

[0044] Among them, IR 发动机 is the infrared radiation intensity in the direction directly behind the engine.

[0045] In at least one embodiment of the present application, the infrared emissivity ε of the turbine solid wall is determined based on the preliminary design results of the component material selection in the engine scheme design stage. 涡轮 , infrared emissivity of the afterburner solid wall ε 加力燃烧室 and the infrared emissivity ε of the nozzle solid wall 喷管 .

[0046] The invention has at least the following beneficial technical effects:

[0047] The comprehensive design method of infrared stealth and aerodynamic thermal performance of aircraft engines in this application takes the comprehensive optimization of infrared stealth indicators and aerodynamic thermal performance indicators as the design goal at the beginning of engine design, analyzes the influence of different coupled design variables on the infrared stealth and aerodynamic thermal performance of the engine, and realizes the comprehensive optimization design of the infrared stealth and aerodynamic thermal performance of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is a flow chart of a comprehensive design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine according to one embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of this application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain this application, and should not be understood as limitations on this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of this application are described in detail below in conjunction with the drawings.

[0050] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as limiting the scope of protection of this application.

[0051] The following is combined with Figure 1 This application is described in further detail.

[0052] This application provides a method for integrated design of infrared stealth and aerodynamic and thermal performance of an aircraft engine, comprising the following steps:

[0053] Step 1: Determine the comprehensive optimization constraints and comprehensive optimization objectives of the engine's infrared stealth and aerodynamic thermal performance. The comprehensive optimization constraints are that the engine performance parameters meet the requirements, and the comprehensive optimization objective is to minimize the engine's forward and backward infrared radiation intensity.

[0054] Step 2: Determine the coupling variables that affect the engine's infrared stealth and aerodynamic and thermodynamic performance, select the engine's aerodynamic and thermodynamic cycle parameters from the coupling variables, and determine multiple different sets of engine aerodynamic and thermodynamic cycle parameters based on the variation range of the coupling variables;

[0055] Step 3: Calculate engine performance parameters and the forward and backward infrared radiation intensity of the engine based on multiple sets of different engine aerodynamic and thermodynamic cycle parameters;

[0056] Step 4: When the engine performance parameters meet the requirements, the values of the engine aerodynamic and thermodynamic cycle parameters are determined based on the principle of minimizing the infrared radiation intensity in the forward and backward directions of the engine, and the comprehensive design of the engine's infrared stealth and aerodynamic and thermodynamic performance is completed.

[0057] The present application discloses a method for the comprehensive design of infrared stealth and aerodynamic and thermal performance of an aircraft engine. First, in step one, based on the comprehensive optimization constraint that the engine performance parameters meet the requirements, the minimum intensity of the engine's forward and backward infrared radiation is added as a comprehensive optimization target. In a preferred embodiment of the present application, the engine performance parameters mainly include thrust, fuel consumption rate, fan and compressor pressure ratio, fan and compressor surge margin, turbine front temperature, etc. The forward and backward infrared radiation of the engine is mainly composed of the thermal wall radiation of the rear-view visible components, the jet radiation, and the reflected radiation of the projected area of the visible area. Since the jet radiation and the reflected radiation of the projected area of the visible area account for a small proportion, they can be ignored in the calculation. Therefore, in the present application, only the thermal wall radiation of the rear-view visible components is considered to perform a one-dimensional rapid calculation of the engine's forward and backward infrared radiation.

[0058] The present application discloses a comprehensive design method for the infrared stealth and aerodynamic and thermal performance of an aero-engine. Secondly, in step 2, the coupling variables affecting the infrared stealth and aerodynamic and thermal performance of the engine are determined, and the engine aerodynamic and thermal cycle parameters are selected from the coupling variables. The engine aerodynamic and thermal cycle parameters mainly include: internal outlet gas flow rate, internal outlet gas temperature, turbine cooling air flow rate, turbine cooling air temperature, afterburner cooling air flow rate, afterburner cooling air temperature, nozzle cooling air flow rate, nozzle cooling air temperature, nozzle throat area, nozzle outlet area, etc.

[0059] In a preferred embodiment of the present application, the process of determining multiple sets of different engine aerodynamic and thermodynamic cycle parameters according to the variation range of the coupling variables is as follows:

[0060] Determine the variation range of each coupling variable based on historical data;

[0061] Determine the preset step size for each coupling variable;

[0062] Determining, according to a preset step size, a plurality of values from a variation range of the coupling variable as values of corresponding engine aerodynamic and thermodynamic cycle parameters;

[0063] The values of the various engine aerodynamic and thermodynamic cycle parameters are combined to obtain multiple groups of different engine aerodynamic and thermodynamic cycle parameters.

[0064] In the historical data that meets the optimization constraints of the aerodynamic and thermodynamic cycle parameters of conventional aircraft engines, the variation range of the coupling variables that affect the engine's infrared stealth and aerodynamic and thermodynamic performance is determined. Within the variation range, the values of each engine's aerodynamic and thermodynamic cycle parameters are adjusted one by one according to a certain step size to form multiple sets of different aircraft engine thermodynamic cycle parameters, which are used for the calculation of engine performance parameters and the engine's forward and backward infrared radiation intensity.

[0065] In the integrated design method for infrared stealth and aerodynamic and thermal performance of aircraft engines of this application, in step three, after obtaining the values of the aerodynamic and thermal cycle parameters of each engine, the engine performance parameters and the forward and backward infrared radiation intensity of the engine are calculated. In a preferred embodiment of this application, the values of the aerodynamic and thermal cycle parameters of each engine are input into the overall performance design software Gasturb, and the engine performance parameters are calculated by the overall performance design software Gasturb.

[0066] In this embodiment, the calculation process of the infrared radiation intensity of the engine in the forward and backward directions includes:

[0067] The average temperature of the turbine solid wall visible from behind is calculated based on the engine aerodynamic and thermodynamic cycle parameters:

[0068] T 涡轮 =f(W6, T6, W 涡轮冷却气 , T 涡轮冷却气 );

[0069] Calculate the average temperature of the solid wall of the afterburner chamber visible from the rear view according to the engine aerodynamic and thermodynamic cycle parameters:

[0070] T 加力燃烧室 =f(W6, T6, W 加力燃烧室冷却气 , T 加力燃烧室冷却气 );

[0071] The average temperature of the solid wall of the rear-view nozzle is calculated based on the engine aerodynamic and thermodynamic cycle parameters:

[0072] T 喷管 =f(W6, T6, W 喷管冷却气 , T 喷管冷却气 );

[0073] Among them, T 涡轮 is the average temperature of the turbine solid wall visible from behind, T 加力燃烧室is the average temperature of the solid wall of the afterburner visible from behind, T 喷管 is the average temperature of the solid wall of the rear-view nozzle, W6 is the internal outlet gas flow rate, T6 is the internal outlet gas temperature, W 涡轮冷却气 is the turbine cooling air flow rate, T 涡轮冷却气 is the turbine cooling air temperature, W 加力燃烧室冷却气 is the cooling air flow rate of the afterburner, T 加力燃烧室冷却气 is the afterburner coolant temperature, W 喷管冷却气 is the nozzle cooling air flow rate, T 喷管冷却气 is the nozzle cooling gas temperature;

[0074] Calculate the projected area of the turbine visible region based on the engine aerodynamic and thermodynamic cycle parameters:

[0075] A 涡轮 =A8-πR 2 内锥 ;

[0076] Calculate the projected area of the afterburner visible area based on the engine's aerodynamic and thermodynamic cycle parameters:

[0077] A 加力燃烧室 =πR 2 内锥 ;

[0078] Calculate the projected area of the nozzle visible region based on the engine aerodynamic and thermodynamic cycle parameters:

[0079] A 喷管 =A9-A8;

[0080] Among them, A 涡轮 is the projected area of the turbine visible area, A 加力燃烧室 is the projected area of the afterburner visible area, A 喷管 is the projected area of the nozzle visible area, A8 is the nozzle throat area, A9 is the nozzle outlet area, R 内锥 is the radius of the cone inside the afterburner;

[0081] Calculate the intensity of infrared radiation generated by the turbine itself:

[0082] IR 涡轮 =ε 涡轮 σT 4 涡轮 A 涡轮 ;

[0083] Calculate the infrared radiation intensity generated by the afterburner itself:

[0084] IR 加力燃烧室 =ε 加力燃烧室 σT 4 加力燃烧室 A加力燃烧室 ;

[0085] Calculate the infrared radiation intensity generated by the nozzle itself:

[0086] IR 喷管 =ε 喷管 σT 4 喷管 A 喷管 ;

[0087] Among them, IR 涡轮 is the infrared radiation intensity generated by the turbine itself, IR 加力燃烧室 is the infrared radiation intensity generated by the afterburner itself, IR 喷管 is the infrared radiation intensity generated by the nozzle itself, ε 涡轮 is the infrared emissivity of the turbine solid wall, ε 加力燃烧室 is the infrared emissivity of the afterburner solid wall, ε 喷管 is the infrared emissivity of the nozzle solid wall, σ is the Stefan-Boltzmann constant;

[0088] Calculate the infrared radiation intensity from the engine forward and backward:

[0089] IR 发动机 =IR 涡轮 +IR 加力燃烧室 +IR 喷管 ;

[0090] Among them, IR 发动机 is the infrared radiation intensity in the direction directly behind the engine.

[0091] Determine the infrared emissivity ε of the turbine solid wall based on the preliminary design results of component material selection in the engine design phase 涡轮 , infrared emissivity of the afterburner solid wall ε 加力燃烧室 and the infrared emissivity ε of the nozzle solid wall 喷管 .

[0092] The present application discloses a method for the comprehensive design of infrared stealth and aerodynamic and thermal performance of an aero-engine. Finally, in step four, based on the calculation results of the engine performance parameters and the forward and backward infrared radiation intensity of the engine, when the engine performance parameters meet the requirements, the values of the various engine aerodynamic and thermal cycle parameters corresponding to the minimum forward and backward infrared radiation intensity of the engine are obtained. Based on these engine aerodynamic and thermal cycle parameters that affect the engine's infrared stealth and aerodynamic and thermal performance, the comprehensive design of the engine's infrared stealth and aerodynamic and thermal performance is completed.

[0093] The integrated design method of infrared stealth and aerodynamic and thermal performance of an aero-engine disclosed in the present application is suitable for the integrated design of infrared stealth and aerodynamic and thermal performance of a small bypass ratio afterburning turbofan engine. It can realize the integrated optimization design of infrared stealth and aerodynamic and thermal performance of the engine during the engine scheme design stage, while achieving a significant improvement in the infrared stealth performance of the engine while minimizing the impact on engine performance indicators such as thrust and fuel consumption rate, thus providing strong support for the integrated design of the engine.

[0094] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A comprehensive design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine, characterized by: include: Step 1: Determine the comprehensive optimization constraints and comprehensive optimization objectives of the engine's infrared stealth and aerodynamic thermal performance, wherein the comprehensive optimization constraints are that the engine performance parameters meet the requirements, and the comprehensive optimization objective is that the engine's forward and backward infrared radiation intensity is minimized; Step 2: determining coupling variables that affect the infrared stealth and aerodynamic and thermodynamic performance of the engine, selecting engine aerodynamic and thermodynamic cycle parameters from the coupling variables, and determining multiple sets of different engine aerodynamic and thermodynamic cycle parameters based on the variation range of the coupling variables; Step 3: Calculating the engine performance parameters and the forward and backward infrared radiation intensity of the engine based on multiple sets of different engine aerodynamic and thermodynamic cycle parameters; Step 4: Under the condition that the engine performance parameters meet the requirements, the values of the engine aerodynamic and thermodynamic cycle parameters are determined based on the principle of minimizing the infrared radiation intensity in the forward and backward directions of the engine, and the comprehensive design of the engine's infrared stealth and aerodynamic and thermodynamic performance is completed; In step 2, multiple sets of different engine aerodynamic and thermodynamic cycle parameters are determined according to the variation range of the coupling variable, including: determining the variation range of each of the coupling variables based on historical data; determining a preset step size for each of the coupling variables; According to the preset step size, determining a plurality of values from the variation range of the coupling variable as corresponding values of the engine aerodynamic and thermodynamic cycle parameters; The values of the various engine aerodynamic and thermodynamic cycle parameters are combined to obtain multiple groups of different engine aerodynamic and thermodynamic cycle parameters.

2. The integrated design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine according to claim 1 is characterized in that: The engine performance parameters include thrust, fuel consumption rate, fan and compressor pressure ratio, fan and compressor surge margin, and turbine inlet temperature.

3. The integrated design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine according to claim 2 is characterized in that: The engine aerodynamic and thermodynamic cycle parameters include: internal outlet gas flow, internal outlet gas temperature, turbine cooling air flow, turbine cooling air temperature, afterburner cooling air flow, afterburner cooling air temperature, nozzle cooling air flow, nozzle cooling air temperature, nozzle throat area, and nozzle outlet area.

4. The method for comprehensive design of infrared stealth and aerodynamic and thermal performance of an aircraft engine according to claim 3, characterized in that: In step three, the engine performance parameters are calculated using the overall performance design software Gasturb.

5. The integrated design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine according to claim 4 is characterized in that: In step 3, the calculation process of the infrared radiation intensity of the engine in the forward and backward directions includes: The average temperature of the turbine solid wall visible from behind is calculated based on the engine aerodynamic and thermodynamic cycle parameters: <h2 style=";text-align:left;direction:ltr">T<h2 style=";text-align:left;direction:ltr"> 涡轮 <h2 style=";text-align:left;direction:ltr"> =f(W6, T6, W<h2 style=";text-align:left;direction:ltr"> 涡轮冷却气 <h2 style=";text-align:left;direction:ltr"> T<h2 style=";text-align:left;direction:ltr"> 涡轮冷却气 <h2 style=";text-align:left;direction:ltr"> ); The average temperature of the solid wall of the afterburner chamber visible from behind is calculated based on the aerodynamic and thermodynamic cycle parameters of the engine: <h2 style=";text-align:left;direction:ltr">T<h2 style=";text-align:left;direction:ltr"> 加力燃烧室 <h2 style=";text-align:left;direction:ltr"> =f(W6, T6, W<h2 style=";text-align:left;direction:ltr"> 加力燃烧室冷却气 <h2 style=";text-align:left;direction:ltr"> T<h2 style=";text-align:left;direction:ltr"> 加力燃烧室冷却气 <h2 style=";text-align:left;direction:ltr"> ); The average temperature of the solid wall of the rear-view nozzle is calculated based on the engine aerodynamic and thermodynamic cycle parameters: <h2 style=";text-align:left;direction:ltr">T<h2 style=";text-align:left;direction:ltr"> 喷管 <h2 style=";text-align:left;direction:ltr"> =f(W6, T6, W<h2 style=";text-align:left;direction:ltr"> 喷管冷却气 <h2 style=";text-align:left;direction:ltr"> T<h2 style=";text-align:left;direction:ltr"> 喷管冷却气 <h2 style=";text-align:left;direction:ltr"> ); Among them, T 涡轮 is the average temperature of the turbine solid wall visible from behind, T 加力燃烧室 is the average temperature of the solid wall of the afterburner visible from behind, T 喷管 is the average temperature of the solid wall of the rear-view nozzle, W6 is the internal outlet gas flow rate, T6 is the internal outlet gas temperature, W 涡轮冷却气 Turbine cooling air flow, T 涡轮冷却气 is the turbine cooling air temperature, W 加力燃烧室冷却气 is the cooling air flow rate of the afterburner, T 加力燃烧室冷却气 is the afterburner coolant temperature, W 喷管冷却气 is the nozzle cooling air flow rate, T 喷管冷却气 is the nozzle cooling gas temperature; Calculate the projected area of the turbine visible region based on the engine aerodynamic and thermodynamic cycle parameters: A 涡轮 =A8-πR 内锥 2 ; Calculate the projected area of the afterburner visible region based on the engine aerodynamic and thermodynamic cycle parameters: A 加力燃烧室 =πR 内锥 2 ; The projected area of the nozzle visible region is calculated based on the engine aerodynamic and thermodynamic cycle parameters: <h2 style=";text-align:left;direction:ltr">A<h2 style=";text-align:left;direction:ltr"> 喷管 <h2 style=";text-align:left;direction:ltr"> =A9-A8; Among them, A 涡轮 A is the projected area of the turbine visible area, 加力燃烧室 is the projected area of the afterburner visible area, A 喷管 is the projected area of the nozzle visible area, A8 is the nozzle throat area, A9 is the nozzle outlet area, R 内锥 is the radius of the cone inside the afterburner; Calculate the intensity of infrared radiation generated by the turbine itself: IR 涡轮 =e 涡轮 σT 涡轮 4 A 涡轮 ; Calculate the infrared radiation intensity generated by the afterburner itself: IR 加力燃烧室 =e 加力燃烧室 σT 加力燃烧室 4 A 加力燃烧室 ; Calculate the infrared radiation intensity generated by the nozzle itself: IR 喷管 =e 喷管 σT 喷管 4 A 喷管 ; Among them, IR 涡轮 is the infrared radiation intensity generated by the turbine itself, IR 加力燃烧室 is the infrared radiation intensity generated by the afterburner itself, IR 喷管 is the infrared radiation intensity generated by the nozzle itself, ε 涡轮 is the infrared emissivity of the turbine solid wall, ε 加力燃烧室 is the infrared emissivity of the afterburner solid wall, ε 喷管 is the infrared emissivity of the nozzle solid wall, σ is the Stefan-Boltzmann constant; Calculate the infrared radiation intensity from the engine forward and backward: IS 发动机 =IS 涡轮 +IR 加力燃烧室 +IR 喷管 ; Among them, IR 发动机 is the infrared radiation intensity in the direction directly behind the engine.

6. The integrated design method for infrared stealth and aerodynamic and thermal performance of an aircraft engine according to claim 5 is characterized in that: Determine the infrared emissivity ε of the turbine solid wall based on the preliminary design results of component material selection in the engine design phase 涡轮 , infrared emissivity of the afterburner solid wall ε 加力燃烧室 and the infrared emissivity ε of the nozzle solid wall 喷管 .

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