| In the range of flight mach number Mo=3 ~ 7, in order to take the advantage of ramjet and scramjet, a fix-shaped dual-mode scramjet, in which both subsonic and supersonic combustion can be obtained, is used for hypersonic vehicle.There are great differences between ground test of a flight vehicle's aerodynamics and that of a dual-mode scramjet When ground test facilities are used to do experiments on a dual-mode scramjet engine, the components of incoming flow and its parameters, including total pressure, total temperature (or total enthalpy) and velocity must be simulated. At the same time, since the fuel's resident time within a combustor is very short, on the order of one millisecond, it is difficult to measure the flow-fields. So experimental study of dual-mode scramjet engines puts higher demands on simulating capability of ground test facilities and measurement technology, and greatly increases test cost and time. Flight test is more expensive and is taken only as a final means for verification. With the development of computer technology and the advancement of numerical calculation, Computational Fluid Dynamics (CFD) has been applied widely in simulating engine's chemical non-equilibrium flowfields and has emerged as an extremely valuable and cost-effective engineering tool in engine design and flowfield analysis. CFD can be used to do analytical research of aerodynamic parameters in relatively short time, to provide detailed flowfield characteristics, to remedy the limitation of wind tunnel test and measurements, and to offer the foundation for improving the configuration of engine.Although a dual-mode scramjet's configuration is simple and mainly consists of inlet, combustor and wake nozzle, its working process is complicated, especially in the combustor, involving a lot of subjects, including hypersonic aerodynamics, combustion chemistry, etc. The inner flow of a combustor is three-dimensional and complicated, including the interaction of shock wave, deflagration, vortex and boundary layer, and so on. So, combustor is the most important to dual-mode scramjet engine. The computation work of three-dimensional mixing and combustion simulation in combustor is very heavy, having strict requirements on the codes. Up to now, there are few domestic papers on 3-D parallel simulation of combustor flowfields. And abroad papers in this field are published gradually in recent years, with the number of grid about 200,000 to 2,500,000.According to the National Hypersonic Technology Plan, a highly efficient and practical three-dimensional parallel computing software for internal non-equilibrium flowfields of a dual-mode scramjet combustor has been established. In order to save calculating time, the parallelcomputation of simplified experimental dual-mode scramjet combustors has been implemented ona cluster of workstations based on PVM platform in a multidomain-multiprocessor manner. High parallel efficiency and fine results have been obtained. Using about 3,120,000 grid cells and 512 CPUs, the parallel program has been successfully transplanted to the SZ MPP machine for massive parallel computation, giving for the first time the detailed flow properties of a model engine's combustor, offering a thorough performance analysis, and unprecedentedly obtaining some flowfield characteristics.This dissertation is divided into six chapters. In the introduction the review of the research on a dual-mode scramjet combustor both abroad and domestic is presented and the main work of this paper is also presented briefly. Chapter 2 describes the governing equations and the adopted physical and chemical method. Chapter 3 is about the numerical method. A parallel computing software is established independently. This software is a cell-centered finite-volume, structured grid, multi-block code which solves the equations governing inviscid and viscous flow of a calorically perfect gas or of an arbitrary mixture of thermally perfect gas undergoing non-equilibrium chemical reactions. It allows the flow domain to be d...
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