In this paper,the AUSMPW scheme based on adaptive algorithm of multi-wavelets is presented to solve two dimensional Euler equations.This scheme based on the original AUSMPW scheme uses the multiwavelets for multi-leve...In this paper,the AUSMPW scheme based on adaptive algorithm of multi-wavelets is presented to solve two dimensional Euler equations.This scheme based on the original AUSMPW scheme uses the multiwavelets for multi-level decomposition of the function and uses the method of the valve's value to construct adaptive grid to improve AUSMPW scheme.The obtained press and density have beed compared with those of results calculated by original AUSMPW scheme and WENO scheme.The numerical results demonstrate that this method has higher resolution.展开更多
The previously developed single-sweep parabolized Navier-Stokes （SSPNS） space marching code for ideal gas flows has been extended to compute chemically nonequilibrium flows. In the code, the strongly coupled set of ...The previously developed single-sweep parabolized Navier-Stokes （SSPNS） space marching code for ideal gas flows has been extended to compute chemically nonequilibrium flows. In the code, the strongly coupled set of gas dynamics, species conservation, and turbulence equations is integrated with the implicit lower-upper symmetric GaussSeidel （LU-SGS） method in the streamwise direction in a space marching manner. The AUSMPW＋ scheme is used to calculate the inviscid fluxes in the crossflow direction, while the conventional central scheme for the viscous fluxes. The k-g two-equation turbulence model is used. The revised SSPNS code is validated by computing the Burrows-Kurkov non-premixed H2/air supersonic combustion flows, premixed H2/air hypersonic combustion flows in a three-dimensional duct with a 15° compression ramp, as well as the hypersonic laminar chemically nonequilibrium air flows around two 10° half-angle cones. The results of these calculations are in good agreement with those of experiments, NASA UPS or Prabhu＇s PNS codes. It can be concluded that the SSPNS code is highly efficient for steady supersonic/ hypersonic chemically reaction flows when there is no large streamwise separation.展开更多
With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new up...With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new upwind scheme called AUSMPWM in this paper.This scheme computes the numerical mass flux as the AUSMPW+and computes the interfacial sound speed in a different way.Also,it computes the pressure flux by limiting the dissipation if the Mach number is less than 1.Series of numerical experiments show that AUSMPWM can satisfy the following attractive properties independent of any tuning coefficient:(1)Robustness against the shock anomaly and high discontinuity’s resolution;(2)high accuracy on hypersonic heating prediction and capability to give smooth reproductions of heating profiles;(3)low dissipation at low speeds;and(4)strong grid,reconstruction scheme,and Mach number independence in low speeds’simulations.These properties suggest that AUSMPWM is promising to be widely used to accurately and efficiently simulate flows of all speeds.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.50476028)
文摘In this paper,the AUSMPW scheme based on adaptive algorithm of multi-wavelets is presented to solve two dimensional Euler equations.This scheme based on the original AUSMPW scheme uses the multiwavelets for multi-level decomposition of the function and uses the method of the valve's value to construct adaptive grid to improve AUSMPW scheme.The obtained press and density have beed compared with those of results calculated by original AUSMPW scheme and WENO scheme.The numerical results demonstrate that this method has higher resolution.
基金supported by the National Natural Science Foundation of China (51176003)
文摘The previously developed single-sweep parabolized Navier-Stokes （SSPNS） space marching code for ideal gas flows has been extended to compute chemically nonequilibrium flows. In the code, the strongly coupled set of gas dynamics, species conservation, and turbulence equations is integrated with the implicit lower-upper symmetric GaussSeidel （LU-SGS） method in the streamwise direction in a space marching manner. The AUSMPW＋ scheme is used to calculate the inviscid fluxes in the crossflow direction, while the conventional central scheme for the viscous fluxes. The k-g two-equation turbulence model is used. The revised SSPNS code is validated by computing the Burrows-Kurkov non-premixed H2/air supersonic combustion flows, premixed H2/air hypersonic combustion flows in a three-dimensional duct with a 15° compression ramp, as well as the hypersonic laminar chemically nonequilibrium air flows around two 10° half-angle cones. The results of these calculations are in good agreement with those of experiments, NASA UPS or Prabhu＇s PNS codes. It can be concluded that the SSPNS code is highly efficient for steady supersonic/ hypersonic chemically reaction flows when there is no large streamwise separation.
基金supported by the National Basic Research Program of China("973"Project)(Grant No.2009CB724104)
文摘With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new upwind scheme called AUSMPWM in this paper.This scheme computes the numerical mass flux as the AUSMPW+and computes the interfacial sound speed in a different way.Also,it computes the pressure flux by limiting the dissipation if the Mach number is less than 1.Series of numerical experiments show that AUSMPWM can satisfy the following attractive properties independent of any tuning coefficient:(1)Robustness against the shock anomaly and high discontinuity’s resolution;(2)high accuracy on hypersonic heating prediction and capability to give smooth reproductions of heating profiles;(3)low dissipation at low speeds;and(4)strong grid,reconstruction scheme,and Mach number independence in low speeds’simulations.These properties suggest that AUSMPWM is promising to be widely used to accurately and efficiently simulate flows of all speeds.
