Performance Investigation Of Higher Mach Number Scramjet Engine With Integrated Compression-heating Processes

The high Mach scramjet(HMSJ)is an important direction for the development of hypersonic technology,and it is also an important way to develop hypersonic cruise missiles and perform air-to-orbit missions in the future.With the increase of the incoming flow Mach number,the thrust-resistance contradiction faced by the HMSJ has gradually become prominent.Therefore,there is an urgent need to carry out research on the matching and enhancement of integrated performance.Aiming at HMSJ,this work has carried out the compression-heating integrated full-channel design and analysis.The inlet injection is used to extend the fuel mixing length and promote the mixing of fuel and air to achieve combustion enhancement.The research is mainly divided into two parts:quasi-one-dimensional modeling analysis and numerical simulation analysis.The main research contents are as follows:(1)Investigation and analysis of research results at home and abroad.In view of the current research status of HMSJ,the combustion enhancement measures at high Mach number,especially the domestic and foreign research results of inlet injection,and the development status of scramjet one-dimensional analysis model have been investigated in the literature.The difficulties faced by the HMSJ technology,the feasibility and effectiveness of inlet injection,and the advantages and rationality of the one-dimensional analysis model are preliminary analyzed.(2)Construction of quasi-one-dimensional analysis model of HMSJ.Based on the principle of thermodynamic cycle,a quasi-one-dimensional analysis model is constructed.First,a comparative analysis of different design points is used to determine the geometric configuration of the high Mach number inlet.Then the boundary layer development,inlet injection and inlet heat release are sequentially introduced.,and the performance analysis of the HMSJ inlet is carried out from the perspective of the integration of compression and heating.The inlet exit parameters is used for the calculations of combustion heat release and expansion,so as to obtain the thrust resistance performance of the whole machine.Quasi-one-dimensional analysis of the performance characteristics of inlet injection will provide a reference for subsequent numerical simulation analysis.(3)Numerical simulation of high Mach number inlet injection/heat release.Based on the geometric parameters of the inlet obtained from the quasi-one-dimensional analysis model and preliminary analysis conclusions,a three-dimensional model of the high Mach number inlet is constructed.The flow Mach number,injection vector angle,fuel equivalence ratio,injection position and fuel type are used as variables to compare and analyze the results of the cold state simulation of the inlet,and thereby optimize the inlet injection strategy.Then based on the cold simulation results,select typical operating conditions to simulate the combustion state of the inlet,and further obtain the combustion heat release in the inlet,which provides a reference for the subsequent full-channel numerical simulation and verifies the results of the quasi-one-dimensional analysis model.(4)Simulation research on the integrated performance of the whole flow channel.Based on the injection strategy obtained by the numerical simulation of the inlet,the numerical simulation of the whole machine is carried out.This chapter determines the geometric configuration of the combustion chamber and the tail nozzle components,and compares the mixing and combustion performance of the HMSJ and the thrust specific impulse of the full runner based on inlet injection.Then on the basis of inlet injection,this chapter shortens the length of the combustion chamber to compare the change of the thrust and resistance characteristics of the whole machine,and finally obtains the performance change law with the inlet injection in the HMSJ.Based on the research idea of compression-heating integration,this work takes the thrust and resistance performance of the whole machine as the design goal,and carries out the integrated analysis of the full-flow channel of the HMSJ.This work uses a variety of analysis methods to carry out performance research and optimization of the HMSJ,which has important research significance and can provide reference for subsequent related further research.