The Characteristic Simulation Of Scramjet And The Integration Design Research

With the combat performance demands which include time-sensitive target strike,high-speed penetration and prompt global strike becoming increasingly prominent inthe future war, air breathing hypersonic cruise missile has been one of the mainweapons which are developed in almost every military country. Because of theintegration of air-breathing hypersonic vehicle and scramjet, resulting stronginteraction between air breathing hypersonic vehicle and scramjet performance inaerodynamics, propulsion, cooling and other disciplines, which requires the integrateddesign of hypersonic vehicle and scramjet.Based on the analysis of the hypersonic vehicle and scramjet performanceintegration based on the design requirement, the design process of hypersonicscramjet engine performance and integration, the calculation and optimization theory,numerical analysis, established the hypersonic vehicle and supersonic combustionramjet performance method of system integration design, the preliminary design andperformance analysis of integrated ramjet performance hypersonic and supersoniccombustion completed.In order to obtain the scramjet performance quickly and accurately, the paperstudies the working principle of inlet, isolator, combustion and nozzle, proposed theintegral form of one-dimensional lumped parameter calculation model of geometryconfiguration design and characteristic simulation. And on this basis, the dual modescramjet configuration design and performance of a one-dimensional lumpedparameter model which based on integral form is proposed with the flow equilibriumiterative calculation method at the core and using the virtual area method to realize.In one-dimensional design and simulation of the combustion, the calculation ofparameters in balance reaction in different static temperature, pressure and the amountof fuel gas based on the chemical equilibrium technology of minimum free energy iscompleted, and the critical parameter method to solve the problem of thermal throat insubsonic mode of ramjet is proposed. Also, combined with virtual area method, thecalculation of various modes in dual mode combustion is completed and the solidfoundation of design and simulation of combustion is laid.By using a one-dimensional lumped parameters calculation model based on theintegral form, the scramjet geometry design is completed and the effect of friction andthe relay point correction factors to flow path design of inlet geometry is analyzed andcontrasted with emphasis; the characteristics simulations of each component of scramjet were carried out, and methods to solve calculation of separate supersoniccombustion mode, transonic mode, subsonic combustion mode and maximum fuelsupplied mode are focused on, a detailed description of the solution process and thecalculation results of various modes are given. On this basis, a detailed analysis of theflow balance mechanism of each mode is given, finally the contrast and analysisbetween calculation results and related data is completed, and then verifying thecorrectness of the model. Furthermore, in the engine cycle analysis aspect, theresearch that effect of engine cycle parameters which include the inlet mach numberand fuel and gas ratio in combustion to engine design performance is completed, andthe appropriate value of the cycle parameters are selected; in the aspect of fuel controllaw of engine, maximum fuel supplied mode the engine component characteristics isobtained in different flight state parameters under different engine design parametersby simulation, through regression analysis, the function among the isolator pressurerise, the mach number in the outlet of inlet and the second segment expansion ratio ofcombustion is obtained, and eventually the largest state of the closed-loop control lawwhich chooses the amount of fuel in combustion as control variable and the pressurerise in isolator as controlled variable is established; the overall performance of theengine is simulated, the engine throttle characteristic, speed characteristic and themaximum mode specific thrust characteristics.In the hypersonic vehicle/scramjet performance integration research, consideringthe highly integration characteristics, the structure/properties analysis of coordinationmodel is put forward, hypersonic vehicle/scramjet integrated design method is putforward based on the traditional integration modeling method of aircraft/turbofanengine; the longitudinal surface ballistic missile flight model is used to construct thebooster model; on this basis, the booster/hypersonic vehicle/scramjet performanceintegration model is proposed.The hypersonic vehicle/scramjet performance integration model is used to completehypersonic vehicle/scramjet performance integration design in the given flight profile,the design parameters of scramjet which meet task constraints demand is obtained,and flexibility characteristics the lift and drag characteristics of vehicle, theperformance of scramjet, the scramjet component characteristics and total weight ofvehicle in relay points is obtained along the flight profile through the integrationconstraint assessment and missions analysis. On this basis, the integration designs ofhypersonic vehicle/scramjet engine and booster/vehicle/scramjet engine integrationdesign are finished by using the exterior penalty function method which choose launch total weight and minimum relay point total weight as optimization goals, andthe minimum acceleration which is not less than2.0m/s2in climb phase as constraint,and the mach number in the outlet of inlet, the second segment expansion ratio ofcombustion and the mach number in relay point as optimization variables. The resultsof the research show that the relay point weight decreased1.71%in the hypersonicvehicle/scramjet optimization design, and if the minimum value of the minimumacceleration is reduced to1.5m/s2in climb phase, then the relay point weight can bereduced by8.14%, the relay point weight decreased12.20%when reduced to1.0m/s2;when selecting minimum acceleration which is not less than1.0m/s2in climb phase,the launch total weight decreases13.66%in the integration design of thebooster/hypersonic vehicle/scramjet engine.The paper gives a comprehensive design method for specific flight task consideringhypersonic vehicle performance and dual mode scramjet performance, lays foundationfor the design, simulation and maximum control law design of dual-mode scramjetand the integration design of booster/hypersonic vehicle/scramjet performance.