Investigation And Application Of High-order Weighted Compact Nonlinear Scheme To Thermo-chemical Non-equilibrium Flow Simulations

As the development of Computational Fluid Dynamics,high-order CFD methods have received considerable attention in the research community in recent years because of their computational efficiency and their vast potential for future development.Weighted Compact Nonlinear Scheme(WCNS)are one kind of finite difference methods put up by Deng xiao-gang,which satisfy the geometric conservation law(GCL)and have been applied into simulations of a variety of flow.In this article,WCNS are applied into the simulations of thermo-chemical non-equilibrium flow for the first time,which is the expansion of application of high-order schemes and has strengthen the potential ability of improving the space precision in hypersonic thermo-chemical non-equilibrium flow simulations and capturing the structures in complex flows.Two dimensional high-order codes have been built,which have been applied into classic problems.Influence of different flux schemes and boundary conditions in the space precision has been researched.The results of simulations of supersonic flow show the perfect performance of the codes.Based on the codes of perfect gas,the module of chemical reaction dynamics has been added into the program and these consist the two-dimensional and axis symmetry thermo-chemical non-equilibrium codes using WCNS-E-5.Simulations of cylinder?sphere cone and two-dimensional compression corner flows have been conducted.Current research is concentrated on the robust problem and has put forward some new methods.For example,methods of nonlinear interpolation and viscous terms schemes have been modified.In some computing,component equations and vibration al energy equation have to be reduced to second order.To eliminate the oscillation arising around the shock,grid distribution has been optimizedThe comparison has been made between the results of WCNS-E-5 and MUSCL.The numerical results show that the high-order thermo-chemical non-equilibrium codes can get reasonable distribution of flow parameters,heat flux and flow separation.And WCNS-E-5's convergence of heat flux at the stagnation point is better than MUSCL's.In the simulation of two-dimensional compression corner flows with shock/boundary layer interaction,results show that WCNS-E-5 can capture the flow structure more accurately.Current research has lay the foundation for widely application of high-order schemes in complex hypersonic thermo-chemical non-equilibrium flows and contributed to further study of high temperature non-equilibrium flows and forecast the aerodynamic characteristics of hypersonic vehicle more accurately.