Variable working condition performance analysis method suitable for scramjet engine cooling and power generation integrated system

Abstract

The invention provides a variable working condition performance analysis method suitable for a cooling and power generation integrated system of a scramjet engine, and the method comprises the steps: starting from the wall surface full working condition heat source characteristics of the scramjet engine, building a cooling and power generation integrated system full working condition analysis system comprising design working condition performance analysis and variable working condition performance analysis; a more scientific system performance evaluation mechanism is formed; by executing an optimization algorithm, more accurate system performance analysis and evaluation can be realized based on different component parameters and operation parameter combinations, and full-working-condition efficient control of a cooling and power generation integrated system and a comprehensive thermal management effect of a scramjet engine are facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of integrated thermal management of aircraft engines, and particularly relates to a method for analyzing the off-design performance of an integrated cooling and power generation system under the conditions of wall fluctuating heat sources and limited cold sources of a scramjet engine. Background Art

[0002] At present, scramjet engines are widely used in high-speed advanced aircraft, enabling high Mach number and long-endurance flights in the near space. Due to the extremely high enthalpy incoming flow and combustion heat release during the operation of scramjet engines, more stringent requirements are imposed on the integrated thermal management of such engines and aircraft. The recently emerged integrated cooling and power generation system integrates the thermodynamic cycle and the regenerative cooling system. When it works, the heat energy of the engine wall is converted into electrical energy through thermoelectric conversion, which can effectively reduce the thermal protection pressure of the engine wall and provide continuous power supply for the engine system. However, since the wall heat sources of scramjet engines fluctuate violently with the aircraft operating conditions, the actual operating performance of the integrated cooling and power generation system often deviates significantly from the design expectations, which is not conducive to the effect of integrated thermal management. Therefore, how to scientifically and accurately analyze the true performance of the integrated cooling and power generation system under off-design conditions is an urgent technical problem to be solved in this field. Summary of the Invention

[0003] In view of the above, aiming at the technical problems existing in the field, the invention provides a method for analyzing the off-design performance of an integrated cooling and power generation system applicable to scramjet engines, which specifically includes the following steps:

[0004] Step 1: Extract the engine wall heat source data and aircraft cold source data during the operation of the scramjet engine and the integrated cooling and power generation system;

[0005] Step 2: Based on the extracted heat source data, establish an engine wall heat source characterization model to reflect the heat source characteristics of the engine under design conditions and the heat source fluctuation characteristics under off-design conditions; based on the extracted cold source data, establish a cold source characterization model to reflect the cold source characteristics of the aircraft under design conditions and the characteristics of limited cold sources under off-design conditions

[0006] Step 3: Based on the basic architecture of the integrated system to be analyzed, establish a performance analysis model under design conditions; design an optimization algorithm and an optimization objective based on this performance analysis model; and establish a performance analysis model under off-design conditions, and design an optimization algorithm and an optimization objective based on this performance analysis model; each analysis model is specifically established based on the structure and physical principles of the integrated system and the corresponding mathematical models; the parameters used for performance analysis specifically include the endothermic pressure, turbine inlet temperature, exothermic pressure, and regeneration degree, etc.; the optimization objectives specifically target the power generation, power generation efficiency, and power density, etc.

[0007] Step 4: Use the extracted design condition data, combine with the performance analysis model and corresponding optimization objectives under the design conditions, execute the optimization algorithm, solve the different operation parameter design schemes and corresponding key component characteristic parameters of the integrated system under the design conditions, and obtain the corresponding system performance under the design conditions;

[0008] Step 5: Use the extracted off-design condition data, combine with the performance analysis model and corresponding optimization objectives under the off-design conditions, execute the optimization algorithm, and solve the different operation parameter combination schemes of the integrated system under the off-design conditions; Use the key component characteristic parameters obtained in Step 4 as constraints to judge whether the parameter combination schemes corresponding to different operating conditions meet the requirements. If so, output the operating performance of the cooling and power generation integrated system under this condition; If not, return to re-perform the generation and judgment process of the operation parameter combination scheme;

[0009] Step 6: Synthesize the system performance under the design conditions and the system performance under the off-design conditions obtained in Step 4 and Step 5, and draw the full-condition performance map of the cooling and power generation integrated system.

[0010] Furthermore, the basic architecture of the integrated system to be designed specifically adopts any one of the system types based on the Rankine cycle, Brayton cycle, organic Rankine cycle, etc.

[0011] Furthermore, in Step 3 and Step 4, the optimization algorithm specifically selects any one of the types such as the exact algorithm, heuristic algorithm, meta-heuristic algorithm, approximation algorithm, etc.

[0012] Furthermore, specifically output the key component characteristic parameters including the turbine, compressor, and heat exchanger through Step 4, which are used as constraints for judging the operation parameter combination schemes under off-design conditions in Step 5.

[0013] The above variable condition performance analysis method for the cooling and power generation integrated system applicable to the scramjet engine provided by the present invention starts from the full-condition heat source characteristics of the scramjet engine wall surface, establishes a full-condition analysis system for the cooling and power generation integrated system including design condition performance analysis and off-design condition performance analysis, and forms a more scientific system performance evaluation mechanism; By executing the optimization algorithm, more accurate system performance analysis and evaluation can be realized based on different component parameters and operation parameter combinations, which is beneficial to the full-condition efficient control of the cooling and power generation integrated system and the comprehensive thermal management effect of the scramjet engine. Description of the Drawings

[0014] Figure 1 It is a flow chart of the method provided by the present invention. Detailed Embodiment

[0015] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0016] The method for analyzing the off-design performance of an integrated cooling and power generation system applicable to a scramjet engine provided by the present invention, as Figure 1 shown, specifically includes the following steps:

[0017] Step 1: Extract the heat source data of the engine wall and the cold source data of the aircraft during the operation of the scramjet engine and the integrated cooling and power generation system;

[0018] Step 2: Based on the extracted heat source data, establish a heat source characterization model for the engine wall to reflect the heat source characteristics of the engine under the design conditions and the heat source fluctuation characteristics under off-design conditions; based on the extracted cold source data, establish a cold source characterization model to reflect the cold source characteristics of the aircraft under the design conditions and the limited cold source characteristics under off-design conditions

[0019] Step 3: Based on the basic architecture of the integrated system to be analyzed, establish a performance analysis model under the design conditions; design an optimization algorithm and an optimization objective based on this performance analysis model; and establish a performance analysis model under off-design conditions, and design an optimization algorithm and an optimization objective based on this performance analysis model; each analysis model is specifically established based on the structure and physical principles of the integrated system and the corresponding mathematical models; the parameters used for performance analysis specifically include the heat absorption pressure, the turbine inlet temperature, the heat release pressure, the recuperation rate, etc.; the optimization objectives specifically target the power generation, the power generation efficiency, the power density, etc.;

[0020] Step 4: Use the extracted design condition data, combined with the performance analysis model and the corresponding optimization objective under the design conditions, to execute the optimization algorithm, solve the different operating parameter design schemes and the corresponding key component characteristic parameters of the integrated system under the design conditions, and obtain the corresponding system performance under the design conditions;

[0021] Step 5: Use the extracted off-design data, combined with the performance analysis model and the corresponding optimization objective under off-design conditions, to execute the optimization algorithm, and solve the different operating parameter combination schemes of the integrated system under off-design conditions; use the key component characteristic parameters obtained in Step 4 as constraints to determine whether the parameter combination schemes corresponding to different operating conditions meet the requirements. If so, output the operating performance of the integrated cooling and power generation system under this operating condition; if not, return to re-perform the process of generating and judging the operating parameter combination schemes;

[0022] Step 6: Combine the system performance under the design conditions and the system performance under off-design conditions obtained in Steps 4 and 5, and plot the full-condition performance map of the integrated cooling and power generation system.

[0023] In a preferred embodiment of the present invention, the basic architecture of the integrated system to be designed specifically adopts any one of the system types based on the Rankine cycle, Brayton cycle, organic Rankine cycle, etc.

[0024] In a preferred embodiment of the present invention, the optimization algorithm in Steps 3 and 4 specifically selects any one of the types such as the exact algorithm, heuristic algorithm, meta-heuristic algorithm, approximate algorithm, etc.

[0025] In a preferred embodiment of the present invention, Step 4 specifically outputs the characteristic parameters of the key components including the turbine, compressor, and heat exchanger, which are used as the constraints for judging the combination schemes of various operating parameters under off-design conditions in Step 5.

[0026] It should be understood that the magnitudes of the sequence numbers of the steps in the embodiments of the present invention do not mean the order of execution is prior or subsequent. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0027] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A variable operating condition performance analysis method for an integrated system of scramjet engine cooling and power generation, characterized in that: Specifically, it includes the following steps: Step 1: Extract the engine wall heat source data and aircraft cold source data during the operation of the scramjet engine and the integrated cooling and power generation system; Step 2: Based on the extracted heat source data, establish an engine wall heat source characterization model to reflect the heat source characteristics of the engine under design conditions and the heat source fluctuation characteristics under off-design conditions; Based on the extracted cold source data, establish a cold source characterization model to reflect the cold source characteristics of the aircraft under design conditions and the finite cold source characteristics under off-design conditions; Step 3: Based on the basic architecture of the integrated system to be analyzed, establish a performance analysis model under design conditions; design optimization algorithms and optimization objectives based on this performance analysis model; And establish a performance analysis model under off-design conditions, design optimization algorithms and optimization objectives based on this performance analysis model; each analysis model is specifically established based on the structure and physical principles of the integrated system and the corresponding mathematical models; the parameters used for performance analysis specifically include the endothermic pressure, turbine inlet temperature, exothermic pressure, and regeneration degree; the optimization objectives specifically target the power generation, power generation efficiency, and power density; Step 4: Use the extracted design condition data, combine with the performance analysis model and the corresponding optimization objectives under design conditions to execute the optimization algorithm, solve the different operating parameter design schemes and the corresponding key component characteristic parameters of the integrated system under design conditions, and obtain the corresponding system performance under design conditions; Step 5: Use the extracted off-design condition data, combine with the performance analysis model and the corresponding optimization objectives under off-design conditions to execute the optimization algorithm, solve the different operating parameter combination schemes of the integrated system under off-design conditions; use the key component characteristic parameters obtained in Step 4 as constraints to judge whether the parameter combination schemes corresponding to different operating conditions meet the requirements. If so, output the operating performance of the integrated cooling and power generation system under this operating condition; if not, return to re-generate and judge the operating parameter combination scheme; Step 6: Synthesize the system performance under design conditions and the system performance under off-design conditions obtained in Steps 4 and 5, and draw the full operating condition performance map of the integrated cooling and power generation system.

2. The method according to claim 1, characterized in that: The basic architecture of the integrated system to be designed specifically adopts any one of the system types based on the Rankine cycle, Brayton cycle, and organic Rankine cycle.

3. The method according to claim 1, characterized in that: The optimization algorithms in Steps 3 and 4 specifically select any one of the exact algorithm, heuristic algorithm, meta-heuristic algorithm, and approximation algorithm.

4. The method according to claim 1, characterized in that: Specifically, through Step 4, the key component characteristic parameters including the turbine, compressor, and heat exchanger are output, which are used as constraints for judging the operating parameter combination schemes under off-design conditions in Step 5.

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