An oxygen-enriched staged combustion cycle engine and its performance deviation compensation method

Abstract

This invention relates to an oxygen-enriched staged combustion cycle engine, specifically to an oxygen-enriched staged combustion cycle engine and its performance deviation compensation method. It solves the technical problems of existing engine performance deviation compensation methods, which struggle to ensure engine pass rates while meeting performance accuracy requirements, and the difficulty in accurately and effectively controlling engine performance accuracy. The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine provided by this invention involves setting up a mixture ratio regulator and a thrust regulator, and establishing a static simulation model of the engine. The static simulation model yields the relationships between the thrust regulator and engine thrust, and between the mixture ratio regulator opening and the engine mixture ratio. Then, based on the limit deviation ranges of the main interference factors, the opening ranges of the thrust regulator and mixture ratio regulator are obtained to compensate for engine performance deviations. This achieves targeted compensation for the performance deviations of the oxygen-enriched staged combustion cycle engine without replacing system components.

Description

Technical Field

[0001] This invention relates to an oxygen-enriched staged combustion cycle engine, specifically to an oxygen-enriched staged combustion cycle engine and a method for compensating for performance deviations therein. Background Technology

[0002] The use of oxygen-enriched staged combustion cycle in liquid rocket engines can significantly improve specific impulse performance. However, the system of an oxygen-enriched staged combustion cycle engine is complex, with numerous components that influence each other. When calculating the operating parameters, it is necessary to balance the deviations of the parameters of each component as much as possible so that the performance parameters of the oxygen-enriched staged combustion cycle engine meet the user requirements.

[0003] The following problems typically arise when compensating for performance deviations in oxygen-enriched staged combustion cycle engines:

[0004] 1) High engine performance requirements

[0005] When liquid rocket engines are used in launch vehicles or space launch vehicles, the engine's thrust, mixture ratio and other performance parameters have a significant impact on the rocket's carrying capacity or the launch vehicle's control precision. Therefore, it is necessary to strictly control the engine's performance parameters. However, existing engine performance deviation compensation methods are difficult to meet performance requirements while ensuring the engine's pass rate.

[0006] 2) The engine has many components and its performance varies.

[0007] The performance of each component product is subject to deviations due to processing and assembly processes. At the same time, the performance tests themselves also have deviations. Existing engine performance deviation compensation methods do not distinguish the degree of influence of each component on engine performance, making it difficult to achieve the goal of accurately and effectively controlling engine performance parameters. Summary of the Invention

[0008] The purpose of this invention is to solve the technical problems of existing engine performance deviation compensation methods, which are difficult to ensure the pass rate of the engine while meeting performance requirements, and difficult to accurately and effectively control the engine performance parameters. The invention provides an oxygen-enriched staged combustion cycle engine and its performance deviation compensation method.

[0009] The design concept of this invention is:

[0010] Adjustment elements are installed in the flow path that significantly affects engine performance. The steady-state parameters of the adjustment elements are highly accurate and adjustable, which can compensate for the performance deviations of various components. At the same time, the engine performance can be calibrated by test driving, and the engine performance parameters can be further corrected without replacing the components, thereby meeting the user's requirements for performance accuracy.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] An oxygen-enriched staged combustion cycle engine includes an oxidizer pump, a primary fuel pump, a secondary fuel pump, a gas generator, a turbine, and a thrust chamber;

[0013] The oxidizer pump, primary fuel pump, secondary fuel pump, and turbine are arranged coaxially.

[0014] The inlet of the oxidizer pump is the engine oxidizer inlet, and the outlet is connected to the oxidizer inlet of the gas generator through a pipeline;

[0015] The inlet of the primary fuel pump is the engine fuel inlet, and the outlet is connected to the fuel inlet of the thrust chamber cooling jacket and the inlet of the secondary fuel pump via pipelines.

[0016] The outlet of the secondary fuel pump is connected to the fuel inlet of the gas generator via a pipeline;

[0017] The gas outlet of the gas generator is connected to the turbine inlet via a pipeline, and the turbine outlet is connected to the gas inlet of the thrust chamber.

[0018] Its special feature is:

[0019] It also includes a mixture ratio regulator and a thrust regulator;

[0020] The mixing ratio regulator is installed on the pipeline between the fuel inlet of the thrust chamber cooling jacket and the outlet of the primary fuel pump.

[0021] The thrust regulator is installed on the pipeline between the fuel inlet of the gas generator and the outlet of the secondary fuel pump.

[0022] This invention also provides a method for compensating performance deviations in the above-mentioned oxygen-enriched staged combustion cycle engine, characterized by the following steps:

[0023] Step 1: Establish a static simulation model based on the system parameters of the oxygen-enriched staged combustion cycle engine; the system parameters include performance parameters.

[0024] Step 2: Based on the static simulation model, obtain the relationship between the thrust regulator opening degree, the mixture ratio regulator opening degree, and performance parameters; the performance parameters include engine thrust and engine mixture ratio.

[0025] Step 3: Based on the static simulation model, the sensitivity equation is obtained by taking the interference factors of the oxygen-enriched staged combustion cycle engine as independent variables and the performance parameters as dependent variables.

[0026] Step 4: Dimensionlessize the performance parameters and interference factors to obtain dimensionless quantities, and then substitute the dimensionless quantities into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters to interference factors.

[0027] Step 5: Compare the dimensionless sensitivity of the performance parameters to interference factors, and record the interference factors corresponding to the larger dimensionless sensitivity values ​​as the main interference factors.

[0028] Step 6: Based on production data, test data, and usage requirements, obtain the limit deviation range of the main interference factors, and then calculate the deviation range of the performance parameters based on the limit deviation range of the main interference factors.

[0029] Step 7: Based on the relationship between the thrust regulator opening and engine thrust, the relationship between the mixture ratio regulator opening and engine mixture ratio obtained in Step 2, and the deviation range of performance parameters obtained in Step 6, calculate the opening range of the thrust regulator and mixture ratio regulator required to compensate for the deviation range of performance parameters. Then adjust the opening of the mixture ratio regulator and thrust regulator to compensate for the performance deviation and complete the performance deviation compensation of the oxygen-enriched staged combustion cycle engine.

[0030] Furthermore, in step 1, the performance parameters include engine thrust and engine mixture ratio, then the static simulation model is:

[0031] F=(q mo +q mf )·I+(p e -p a )·A e

[0032]

[0033] P t =P po +P pf

[0034] p epo =p ipo +Δp po

[0035]

[0036] p epf1 =p ipf1 +Δp pf1

[0037]

[0038] o epf2 =p epf1 +Δp pf2

[0039] K = q mo / q mf

[0040] Where F is the engine thrust, qmo q is the oxidant flow rate at the engine oxidant inlet. mf Where p is the fuel flow rate at the engine fuel inlet, I is the engine specific impulse, and p is the fuel flow rate at the engine fuel inlet. e p is the nozzle outlet pressure. a Due to environmental pressures, A e q represents the nozzle exit area. mf =q mfc +q mpf2 q mfc The fuel flow rate in the thrust chamber is α, which is the opening degree of the mixture ratio regulator. thr The function q mpf2 The fuel flow rate of the secondary fuel pump is the thrust regulator opening α. tj The function;

[0041] P po The power of the oxidant pump, Δp po For the head of the oxidizer pump, ρ po η is the propellant density of the oxidizer pump. po The efficiency of the oxidant pump; n is the turbine speed, a po b po c po The fitting coefficient for the head curve of the oxidant pump is obtained from the hydraulic test of the oxidant pump;

[0042] P pf Δp is the total power of the primary and secondary fuel pumps. pf1 For the head of the primary fuel pump, ρ pf1 η is the propellant density of the first-stage fuel pump. pf1 For the efficiency of the first-stage fuel pump, Δp pf2 q is the head of the secondary fuel pump. mof2 ρ is the fuel flow rate of the secondary fuel pump. pf2 η is the propellant density of the secondary fuel pump. pf2 The efficiency of the secondary fuel pump; a pf1 b pf1 c pf1 The fitting coefficient for the head curve of the fuel primary pump is obtained from the hydraulic test of the fuel primary pump. a pf2 b pf2 c pf2 The fitting coefficient for the head curve of the fuel secondary pump is obtained from the hydraulic test of the fuel secondary pump;

[0043] q t η is the power of the turbine. t For the efficiency of the turbine, q mt For the oxidant and fuel flow rates entering the turbine, qmt =q mo +q mpf2 k gg R is the isentropic exponent of the turbine's combustion gases. gg T is the gas constant of the turbine. gg p is the inlet gas temperature of the turbine. et p is the outlet pressure of the turbine. it This refers to the turbine inlet pressure; p c For the pressure in the thrust chamber, ξ etg T is the flow resistance coefficient of the turbine outlet gas path. et The outlet gas temperature of the turbine.

[0044] p epo p is the outlet pressure of the oxidant pump. ipo p is the pressure at the engine oxidant inlet. gg The pressure of the gas generator, ξ ggo ρ is the oxidant path resistance coefficient of the gas generator. epo The density of the oxidant at the outlet of the oxidant pump; ξ ith The inlet gas path resistance coefficient of the turbine;

[0045] p epf1 p is the outlet pressure of the first-stage fuel pump. ipf1 ξ is the pressure at the engine fuel inlet. fc ρ is the total flow resistance coefficient of the fuel supply path in the thrust chamber. epf1 p is the fuel density at the outlet of the primary fuel pump. c =(q mo +q mf )×C * / (π×D 2 / 4), C * The characteristic velocity of the combustion gases in the thrust chamber is determined by the chamber pressure, engine air-fuel ratio, and combustion efficiency. Determined, D is the throat diameter of the thrust chamber; ξ fc =ξ thr (α thr )+ξ tc ξ thr The flow resistance coefficient of the mixing ratio regulator (2) is its opening α. thr The function, ξ tc The flow resistance coefficient of the cooling channel and injector of the thrust chamber;

[0046] p epf2 This is the outlet pressure of the secondary fuel pump;

[0047] K is the engine air-fuel mixture ratio.

[0048] Further, in step 3, the sensitivity equation is:

[0049]

[0050] Among them, (h1,h2,…,h m H represents the interference factors of the oxygen-enriched afterburning cycle engine, including internal and external interference factors. Internal interference factors include the structural and design parameters of the oxygen-enriched afterburning cycle engine, while external interference factors include the engine oxidant inlet pressure, engine fuel inlet pressure, engine oxidant inlet temperature, and engine fuel inlet temperature.

[0051] (x1,x2,…,x n X = X, which are the performance parameters of the oxygen-enriched staged combustion cycle engine;

[0052] Indicates performance parameter x i For interfering factors h j The sensitivity is 1≤i≤n, 1≤j≤m.

[0053] Furthermore, step 4 specifically involves:

[0054] 4.1 Obtain the rated design values ​​of performance parameters and interference factors for the oxygen-enriched staged combustion cycle engine;

[0055] 4.2 Calculate the dimensionless quantities of performance parameters and interference factors according to the following formulas:

[0056]

[0057] Where X represents the actual value, X o Indicates the rated design value. Indicates a dimensionless quantity;

[0058] 4.3 Substitute the dimensionless quantities of the performance parameters and interference factors into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters to the interference factors.

[0059] Furthermore, in step 6, the deviation range of the performance parameter is calculated using the following formula:

[0060]

[0061]

[0062] Where ΔF represents the deviation range of engine thrust, ΔK represents the deviation range of engine air-fuel ratio, and Δh1, Δh2, ..., Δh m h1 represents the limit deviation range of the main interfering factors. o h2o ... h m o This represents the rated design value of the main interference factors. F represents the dimensionless quantity representing the main interfering factor. o K represents the rated design value of engine thrust. o This indicates the rated design value of the engine's air-fuel mixture ratio. A dimensionless quantity representing engine thrust. A dimensionless quantity representing the air-fuel mixture ratio in an engine.

[0063] Compared with the prior art, the present invention has the following beneficial technical effects:

[0064] 1. The performance deviation compensation method for an oxygen-enriched afterburning cycle engine provided by the present invention involves setting a thrust regulator in the fuel line of the gas generator to stabilize or change the flow rate of the line, and setting a mixture ratio regulator in the fuel line of the thrust chamber to change the flow resistance of the fuel line of the thrust chamber. This method can stably adjust the engine thrust and engine mixture ratio, and specifically compensate for performance deviations. Without replacing system components, the engine performance parameters can be corrected, which not only meets the performance requirements, but also ensures the engine's pass rate.

[0065] 2. In the performance deviation compensation method of the oxygen-enriched staged combustion cycle engine provided by the present invention, by establishing a static simulation model of the oxygen-enriched staged combustion cycle engine, the relationship between the performance deviations of the engine thrust and mixture ratio and the opening range of the thrust regulator and the opening range of the mixture ratio regulator is obtained. By adjusting the thrust regulator and the mixture ratio regulator, the deviation caused by interference factors is compensated.

[0066] 3. In the performance deviation compensation method of the oxygen-enriched afterburning cycle engine provided by the present invention, by making the interference factors and performance parameters dimensionless, the dimensionless sensitivity of the performance parameters to the interference factors can be obtained, which can evaluate the degree of influence of the interference factors on the engine performance, thereby effectively identifying the interference factors that have a significant impact on the engine performance and achieving precise control of the engine performance parameters. Attached Figure Description

[0067] Figure 1 This is a schematic diagram of the structure of the oxygen-enriched staged combustion cycle engine in an embodiment of the present invention;

[0068] The annotations in the attached figures are explained as follows:

[0069] 1-Thrust chamber, 2-Mix ratio regulator, 3-Thrust regulator, 4-Gas generator, 5-Turbine, 6-Oxidant pump, 7-First-stage fuel pump, 8-Second-stage fuel pump. Detailed Implementation

[0070] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a further detailed explanation of the oxygen-enriched staged combustion cycle engine and its performance deviation compensation method proposed in this invention. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this invention and are not intended to limit the scope of protection of this invention.

[0071] An oxygen-enriched staged combustion cycle engine, such as Figure 1 The system includes an oxidizer pump 6, a primary fuel pump 7, a secondary fuel pump 8, a gas generator 4, a turbine 5, and a thrust chamber 1, as well as a mixture ratio regulator 2 and a thrust regulator 3.

[0072] Oxidizer pump 6, primary fuel pump 7, secondary fuel pump 8, and turbine 5 are coaxially arranged. The inlet of oxidizer pump 6 is the engine oxidizer inlet, and its outlet is connected to the oxidizer inlet of gas generator 4 via a pipeline. The inlet of primary fuel pump 7 is the engine fuel inlet, and its outlet is connected to the fuel inlet of the cooling jacket of thrust chamber 1 and the inlet of secondary fuel pump 8 via pipelines. The outlet of secondary fuel pump 8 is connected to the fuel inlet of gas generator 4 via a pipeline. The gas outlet of gas generator 4 is connected to the inlet of turbine 5 via a pipeline, and the outlet of turbine 5 is connected to the gas inlet of thrust chamber 1. Mixture ratio regulator 2 is located on the pipeline between the fuel inlet of the cooling jacket of thrust chamber 1 and the outlet of primary fuel pump 7, and thrust regulator 3 is located on the pipeline between the fuel inlet of gas generator 4 and the outlet of secondary fuel pump 8. The steady-state parameters of mixture ratio regulator 2 and thrust regulator 3 are highly accurate and adjustable, and engine performance can be calibrated through test runs to compensate for performance deviations in various system components.

[0073] This invention also provides a method for compensating performance deviations in an oxygen-enriched staged combustion cycle engine, using the aforementioned oxygen-enriched staged combustion cycle engine, comprising the following steps:

[0074] Step 1: Establish a static simulation model based on the system parameters of the oxygen-enriched staged combustion cycle engine. The system parameters include performance parameters.

[0075] The static simulation model is as follows:

[0076] F=(q mo +q mf )·I+(p e -p a )·A e

[0077]

[0078] P t =P po +P pf

[0079] o epo =pipo +Δp po

[0080]

[0081] p epf1 =p ipf1 +Δp pf1

[0082]

[0083] o epf2 =p epf1 +Δp pf2

[0084] K = q mo / q mf

[0085] Where F is the engine thrust, q mo q is the oxidant flow rate at the engine oxidant inlet. mf Where p is the fuel flow rate at the engine fuel inlet, I is the engine specific impulse, and p is the fuel flow rate at the engine fuel inlet. e p is the nozzle outlet pressure. a Due to environmental pressures, A e q represents the nozzle exit area. mf =q mfc +q mpf2 q mfc The fuel flow rate of thrust chamber 1 is α, which is the opening degree of mixture ratio regulator 2. thr The function q mpf2 The fuel flow rate of the secondary fuel pump 8 is the opening α of the thrust regulator 3. tj The function;

[0086] P po For the power of oxidant pump 6, Δp po For the head of oxidizer pump 6, ρ po η is the propellant density of oxidizer pump 6. po The efficiency of oxidant pump 6; n is the rotational speed of turbine 5, a po b po c po The fitting coefficient for the head curve of oxidant pump 6 is obtained from the hydraulic test of oxidant pump 6;

[0087] P pf The total power of fuel primary pump 7 and fuel secondary pump 8, Δp pf1 For the head of fuel primary pump 7, ρ pf1 η is the propellant density of fuel primary pump 7. pf1 For the efficiency of fuel primary pump 7, Δppf2 For the head of the secondary fuel pump 8, q mpf2 For the fuel flow rate of the secondary fuel pump 8, ρ pf2 η is the propellant density of the secondary fuel pump 7. pf2 The efficiency of the secondary fuel pump; a pf1 b pf1 c pf1 The fitting coefficient for the head curve of fuel primary pump 7 is obtained from the hydraulic test of fuel primary pump 7; a pf2 b pf2 c pf2 The fitting coefficient for the head curve of the fuel secondary pump 8 is obtained from the hydraulic test of the fuel secondary pump 8;

[0088] P t For the power of turbine 5, η t For the efficiency of Turbo 5, q mt For the oxidizer and fuel flow entering turbine 5, q mt =q mo +q mpf2 k gg R is the isentropic index of the Turbo 5 gas flow. gg T is the gas constant of turbine 5. gg p is the inlet gas temperature of turbine 5. et p is the outlet pressure of turbine 5. it This is the inlet pressure of turbine 5; p c For the pressure in thrust chamber 1, ξ etg T is the flow resistance coefficient of the outlet gas path of turbine 5. et The outlet gas temperature of turbine 5.

[0089] p epo p is the outlet pressure of oxidant pump 6. ipo p is the pressure at the engine oxidant inlet. gg The pressure of gas generator 4, ξ ggo ρ is the oxidant path flow resistance coefficient of gas generator 4. epo The density of the oxidant at the outlet of oxidant pump 6; ξ itg The inlet gas path resistance coefficient of turbine 5;

[0090] p epf1 p is the outlet pressure of fuel primary pump 7. ipf1 ξ is the pressure at the engine fuel inlet. fcρ is the total flow resistance coefficient of the fuel supply path in thrust chamber 1. epf1 The fuel density at the outlet of fuel primary pump 7; p c =(q mo +q mf )×C * / (π×D 2 / 4), C * The characteristic velocity of the gas in thrust chamber 1 is determined by the chamber pressure of thrust chamber 1, the engine air-fuel mixture ratio, and the combustion efficiency. It is determined that D is the throat diameter of thrust chamber 1; ξ fc =ξ thr (α thr )+ξ tc ξ thr The flow resistance coefficient of the mixing ratio regulator 2 is its opening α. thr The function, ξ tc The flow resistance coefficients of the cooling channel and injector of thrust chamber 1;

[0091] p epf2 The outlet pressure of the secondary fuel pump 8;

[0092] K is the engine air-fuel mixture ratio.

[0093] The performance parameters in the static simulation model are hydraulic test values ​​or statistical characteristics. The correctness of the static simulation model can be verified by the test data of the engine.

[0094] Step 2: Based on the static simulation model, obtain the relationship between the opening degree of the thrust regulator 3, the opening degree of the mixture ratio regulator 2 and the performance parameters, namely the relationship between the opening degree of the thrust regulator 3 and the engine thrust, and the relationship between the opening degree of the mixture ratio regulator 2 and the engine mixture ratio.

[0095] Step 3: Based on the static simulation model, using the disturbance factors of the oxygen-enriched staged combustion cycle engine as independent variables and the performance parameters as dependent variables, the sensitivity equation is obtained. The disturbance factors include internal and external disturbance factors. Internal disturbance factors include the structural and design parameters of the oxygen-enriched staged combustion cycle engine, and the fitting coefficient α of the head curve of the oxidizer pump 6. po b po c po The oxidant path resistance coefficient ξ of gas generator 4 gg External disturbance factors include engine oxidizer inlet pressure, engine fuel inlet pressure, engine oxidizer inlet temperature, and engine fuel inlet temperature.

[0096] The sensitivity equation is as follows:

[0097]

[0098] Among them, (h1,h2,…,h m H is the interfering factor for the oxygen-enriched afterburning cycle engine.

[0099] (x1,x2,…,x n X = X, which are the performance parameters of the oxygen-enriched staged combustion cycle engine;

[0100] Indicates performance parameter x i For interfering factors h j The sensitivity is 1≤i≤n, 1≤j≤m.

[0101] Step 4: Dimensionlessly convert the performance parameters and interfering factors to dimensionless quantities. Then, substitute these dimensionless quantities into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters to the interfering factors. Specifically:

[0102] 4.1 Obtain the rated design values ​​of performance parameters and interference factors of the oxygen-enriched staged combustion cycle engine.

[0103] 4.2 Calculate the dimensionless quantities of performance parameters and interference factors according to the following formulas:

[0104]

[0105] Where X represents the actual value, X o Indicates the rated design value. It represents a dimensionless quantity.

[0106] For example, the actual value of engine thrust Actual value of engine air-fuel ratio Actual value of the throat diameter of thrust chamber 1

[0107] 4.3 Substitute the dimensionless quantities of the performance parameters of each component of the system and the interference factors into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters of each component of the system to the interference factors.

[0108] Dimensionlessness allows for comparison of the significance of interference factors on performance parameters, thereby identifying the main interference factors. Therefore, it is necessary to introduce the characteristic values ​​of each variable, i.e., the rated parameters, including the rated design values ​​of interference factors and the rated values ​​of the performance parameters of each component of the system.

[0109] Step 5: Compare the dimensionless sensitivity of the performance parameters to interference factors, and record the interference factors corresponding to the larger dimensionless sensitivity values ​​as the main interference factors.

[0110] Step 6: Based on production data, test data, and usage requirements, obtain the limit deviation range of the main interference factors, and then calculate the deviation range of the performance parameters based on the limit deviation range of the main interference factors.

[0111] The deviation range of the performance parameters is calculated using the following formula:

[0112]

[0113] Where ΔF represents the deviation range of engine thrust, ΔK represents the deviation range of engine air-fuel ratio, and Δh1, Δh2, ..., Δh m h1 represents the limit deviation range of the main interfering factors. o h2 o ... h m o This represents the rated design value of the main interference factors. F represents the dimensionless quantity representing the main interfering factor. o K represents the rated design value of engine thrust. o This indicates the rated design value of the engine's air-fuel ratio. A dimensionless quantity representing engine thrust. A dimensionless quantity representing the air-fuel mixture ratio in an engine.

[0114] Step 7: Based on the relationship between the opening degree of thrust regulator 3 and engine thrust, the relationship between the opening degree of mixture ratio regulator 2 and engine mixture ratio obtained in Step 2, and the deviation range of performance parameters obtained in Step 6, calculate the opening degree range of thrust regulator 3 and mixture ratio regulator 2 required to compensate for the deviation range of performance parameters. Then adjust the opening degree of mixture ratio regulator 2 and thrust regulator 3 to compensate for performance deviation and complete the performance deviation compensation of the oxygen-enriched staged combustion cycle engine.

[0115] The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine proposed in this invention can be applied in the development of an oxygen-enriched staged combustion cycle engine with ambient temperature propellant. By setting a thrust regulator and a mixture ratio regulator in the oxygen-enriched staged combustion cycle engine and establishing a static simulation model of the engine, the relationship between the thrust regulator and engine thrust, and between the mixture ratio regulator opening degree and engine mixture ratio can be obtained through the static simulation model. The opening range of the thrust regulator and the opening range of the mixture ratio regulator can be obtained through the limit deviation range of the main interference factors, thereby compensating for the engine's performance deviation. Thus, targeted compensation for performance deviation can be achieved without replacing system components.

Claims

1. A method for compensating performance deviations of an oxygen-enriched afterburning cycle engine, wherein the oxygen-enriched afterburning cycle engine comprises an oxidizer pump (6), a primary fuel pump (7), a secondary fuel pump (8), a gas generator (4), a turbine (5), and a thrust chamber (1); The oxidizer pump (6), the primary fuel pump (7), the secondary fuel pump (8), and the turbine (5) are arranged coaxially; The inlet of the oxidizer pump (6) is the engine oxidizer inlet, and the outlet is connected to the oxidizer inlet of the gas generator (4) through a pipeline; The inlet of the primary fuel pump (7) is the engine fuel inlet, and the outlet is connected to the fuel inlet of the cooling jacket of the thrust chamber (1) and the inlet of the secondary fuel pump (8) through pipelines. The outlet of the secondary fuel pump (8) is connected to the fuel inlet of the gas generator (4) via a pipeline; The gas outlet of the gas generator (4) is connected to the inlet of the turbine (5) through a pipeline, and the outlet of the turbine (5) is connected to the gas inlet of the thrust chamber (1). It also includes a mixture ratio regulator (2) and a thrust regulator (3); The mixing ratio regulator (2) is installed on the pipeline between the fuel inlet of the cooling jacket of the thrust chamber (1) and the outlet of the primary fuel pump (7); The thrust regulator (3) is installed on the pipeline between the fuel inlet of the gas generator (4) and the outlet of the secondary fuel pump (8); Its features are, Includes the following steps: Step 1: Establish a static simulation model based on the system parameters of the oxygen-enriched staged combustion cycle engine; the system parameters include performance parameters. Step 2: Based on the static simulation model, obtain the relationship between the opening degree of the thrust regulator (3), the opening degree of the mixture ratio regulator (2), and the performance parameters; Step 3: Based on the static simulation model, the sensitivity equation is obtained by taking the interference factors of the oxygen-enriched staged combustion cycle engine as independent variables and the performance parameters as dependent variables. Step 4: Dimensionlessize the performance parameters and interference factors to obtain dimensionless quantities, and then substitute the dimensionless quantities into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters to interference factors. Step 5: Compare the dimensionless sensitivity of the performance parameters to interference factors, and record the interference factors corresponding to the larger dimensionless sensitivity values ​​as the main interference factors. Step 6: Based on production data, test data, and usage requirements, obtain the limit deviation range of the main interference factors, and then calculate the deviation range of the performance parameters based on the limit deviation range of the main interference factors. Step 7: Based on the relationship between the opening degree of the thrust regulator (3), the opening degree of the mixture ratio regulator (2) and the performance parameters obtained in Step 2, and the deviation range of the performance parameters obtained in Step 6, calculate the opening degree range of the thrust regulator (3) and the mixture ratio regulator (2) required to compensate for the deviation range of the performance parameters. Then adjust the opening degree of the mixture ratio regulator (2) and the thrust regulator (3) to compensate for the performance deviation and complete the performance deviation compensation of the oxygen-rich afterburning cycle engine.

2. The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine according to claim 1, characterized in that, In step 1, the performance parameters include engine thrust and engine mixture ratio, so the static simulation model is: F=(q mo +q mf )·I+(p e -p a )·A e P t =P po +P pf p epo =p ipo +Δp po p epf1 =p ipf1 +Δp pf1 p epf2 =p epf1 +Δp pf2 K=q mo / q mf Where F is the engine thrust, q mo q is the oxidant flow rate at the engine oxidant inlet. mf Where p is the fuel flow rate at the engine fuel inlet, I is the engine specific impulse, and p is the fuel flow rate at the engine fuel inlet. e p is the nozzle outlet pressure. a Due to environmental pressures, A e q represents the nozzle exit area. mf =q mfc +q mpf2 q mfc The fuel flow rate in the thrust chamber (1) is the opening α of the mixture ratio regulator (2). thr The function q mpf2 The fuel flow rate of the secondary fuel pump (8) is the opening α of the thrust regulator (3). tj The function; P po The power of the oxidant pump (6), Δp po For the head of the oxidant pump (6), ρ po η is the propellant density of the oxidizer pump (6). po The efficiency of the oxidant pump (6); n is the rotational speed of the turbine (5), a po b po c po The fitting coefficient for the head curve of the oxidant pump (6) is obtained from the hydraulic test of the oxidant pump (6); P pf The total power of the primary fuel pump (7) and the secondary fuel pump (8), Δp pf1 For the head of the primary fuel pump (7), ρ pf2 η is the propellant density of the first-stage fuel pump (7). pf1 For the efficiency of the first-stage fuel pump (7), Δp pf2 For the head of the secondary fuel pump (8), q mpf2 ρ is the fuel flow rate of the secondary fuel pump (8). pf2 η is the propellant density of the secondary fuel pump (7). pf2 The efficiency of the secondary fuel pump (7); a pf1 b pf1 c pf1 The fitting coefficient for the head curve of the fuel primary pump (7) is obtained from the hydraulic test of the fuel primary pump (7); a pf2 b pf2 c pf2 The fitting coefficient for the head curve of the fuel secondary pump (8) is obtained from the hydraulic test of the fuel secondary pump (8); P t For the power of turbine (5), η t For the efficiency of turbine (5), q mt For the oxidant and fuel flow rate entering the turbine (5), q mt =q mo +q mpf2 k gg R is the isentropic exponent of the gas in the turbine (5). gg T is the gas constant of the turbine (5). gg p is the inlet gas temperature of the turbine (5). et p is the outlet pressure of the turbine (5). it The inlet pressure of the turbine (5); p c For the pressure in the thrust chamber (1), ξ etg T is the flow resistance coefficient of the outlet gas path of the turbine (5). et The outlet gas temperature of the turbine (5) p epo p is the outlet pressure of the oxidant pump (6). ipo p is the pressure at the engine oxidant inlet. gg The pressure of the gas generator (4), ξ ggo ρ is the oxidant path resistance coefficient of the gas generator (4). epo The oxidant density at the outlet of the oxidant pump (6); ξ itg The inlet gas path resistance coefficient of the turbine (5); p epf1 p is the outlet pressure of the primary fuel pump (7). ipf1 ξ is the pressure at the engine fuel inlet. fc ρ is the total flow resistance coefficient of the fuel supply path in the thrust chamber (1). epf1 The fuel density at the outlet of the primary fuel pump (7); p c =(q mo +q mf )×C * / (π×D 2 / 4), C * The characteristic velocity of the combustion gas in the thrust chamber (1) is determined by the chamber pressure of the thrust chamber (1), the engine mixture ratio, and the combustion efficiency. It is determined that D is the throat diameter of the thrust chamber (1); ξ fc =ξ thr (α thr )+ξ tc ξ thr The flow resistance coefficient of the mixing ratio regulator (2) is its opening α. thr The function, ξ tc The flow resistance coefficient of the cooling channel and injector of the thrust chamber (1); p epf2 The outlet pressure of the secondary fuel pump (8); K is the engine air-fuel mixture ratio.

3. The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine according to claim 2, characterized in that, In step 3, the sensitivity equation is: Among them, (h1,h2,…,h m H represents the interference factors of the oxygen-enriched staged combustion cycle engine, including internal interference factors and external interference factors. Internal interference factors include the structural parameters and design parameters of the oxygen-enriched staged combustion cycle engine, while external interference factors include the engine oxidant inlet pressure, engine fuel inlet pressure, engine oxidant inlet temperature, and engine fuel inlet temperature. (x1,x2,…,x n X represents the performance parameters of an oxygen-enriched staged combustion cycle engine. Indicates performance parameter x i For interfering factors h j The sensitivity is 1≤i≤n, 1≤j≤m.

4. The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine according to claim 3, characterized in that, Step 4 is as follows: 4.1 Obtain the rated design values ​​of performance parameters and interference factors for the oxygen-enriched staged combustion cycle engine; 4.2 Calculate the dimensionless quantities of performance parameters and interference factors according to the following formulas: Where X represents the actual value, X o Indicates the rated design value. Indicates a dimensionless quantity; 4.3 Substitute the dimensionless quantities of the performance parameters and interference factors into the sensitivity equation to obtain the dimensionless sensitivity of the performance parameters to the interference factors.

5. The performance deviation compensation method for an oxygen-enriched staged combustion cycle engine according to claim 4, characterized in that, In step 6, the deviation range of the performance parameters is calculated using the following formula: Where ΔF represents the deviation range of engine thrust, ΔK represents the deviation range of engine air-fuel ratio, and Δh1, Δh2, ..., Δh m h1 represents the limit deviation range of the main interfering factors. o h2 o ... h m o This represents the rated design value of the main interference factors. F represents the dimensionless quantity representing the main interfering factor. o K represents the rated design value of engine thrust. o This indicates the rated design value of the engine's air-fuel ratio. A dimensionless quantity representing engine thrust. A dimensionless quantity representing the air-fuel mixture ratio in an engine.

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