In the design of a hypersonic airliner that can considerably shorten the flight time, how to accurately predict the vehicle's aerodynamic heating loads is of great significance. In this study, a new shock-stable f...In the design of a hypersonic airliner that can considerably shorten the flight time, how to accurately predict the vehicle's aerodynamic heating loads is of great significance. In this study, a new shock-stable flux scheme called the simple low dissipation advection upwind splitting method(SLAU)-M1 is proposed for the prediction of hypersonic aerodynamic heating load. Based on the construction of the SLAU scheme for low-speed simulations, SLAU-M1 improves the robustness of the mass flux against shock instability. After validating the code employed, several numerical test cases are conducted. The onedimensional(1D) sod shock tube case and the two-dimensional(2D) inviscid NACA0012 airfoil case show that SLAU-M1 features a high level of accuracy at both low and high speeds. To simulate the hypersonic viscous flow over a blunt cone, we adopt different aspect ratios(ARs) of cells near the shock. The results suggest that SLAU-M1 is much less sensitive to the AR of cells near the shock in predicting hypersonic aerodynamic heating loads. Moreover, the findings show that the theoretical value is considerably better than that of the other schemes. The hypersonic viscous flow over a 2D double ellipsoid case and that over the Hypersonic Flight Experiment vehicle case also indicate that SLAU-M1 exhibits a considerably high level of accuracy in hypersonic heating predictions. These properties suggest that SLAU-M1 promises to be widely used in the accurate prediction of the aerodynamic heating loads of hypersonic airliners.展开更多
Nowadays,the upwind schemes are in a rapid development to capture shock accurately.However,these upwind schemes’properties at low speeds,such as their reconstruction scheme dependencies,grid dependencies,and Mach num...Nowadays,the upwind schemes are in a rapid development to capture shock accurately.However,these upwind schemes’properties at low speeds,such as their reconstruction scheme dependencies,grid dependencies,and Mach number dependencies,are concerned by few people.In this paper,a systematic study on their low speeds’issues is conducted.Through a series of tests,we can find that most parameter-free upwind schemes,widely used in practice today,are not applicable to low speeds’simulations.In contrast,SLAU and SLAU2 can give reliable results.Also,the upwind scheme’s influence on the accuracy is stronger than the reconstruction scheme’s influence at low speeds.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11802245)
文摘In the design of a hypersonic airliner that can considerably shorten the flight time, how to accurately predict the vehicle's aerodynamic heating loads is of great significance. In this study, a new shock-stable flux scheme called the simple low dissipation advection upwind splitting method(SLAU)-M1 is proposed for the prediction of hypersonic aerodynamic heating load. Based on the construction of the SLAU scheme for low-speed simulations, SLAU-M1 improves the robustness of the mass flux against shock instability. After validating the code employed, several numerical test cases are conducted. The onedimensional(1D) sod shock tube case and the two-dimensional(2D) inviscid NACA0012 airfoil case show that SLAU-M1 features a high level of accuracy at both low and high speeds. To simulate the hypersonic viscous flow over a blunt cone, we adopt different aspect ratios(ARs) of cells near the shock. The results suggest that SLAU-M1 is much less sensitive to the AR of cells near the shock in predicting hypersonic aerodynamic heating loads. Moreover, the findings show that the theoretical value is considerably better than that of the other schemes. The hypersonic viscous flow over a 2D double ellipsoid case and that over the Hypersonic Flight Experiment vehicle case also indicate that SLAU-M1 exhibits a considerably high level of accuracy in hypersonic heating predictions. These properties suggest that SLAU-M1 promises to be widely used in the accurate prediction of the aerodynamic heating loads of hypersonic airliners.
基金supported by the National Basic Research Program of China("973" Project)(Grant No.2009CB724104)
文摘Nowadays,the upwind schemes are in a rapid development to capture shock accurately.However,these upwind schemes’properties at low speeds,such as their reconstruction scheme dependencies,grid dependencies,and Mach number dependencies,are concerned by few people.In this paper,a systematic study on their low speeds’issues is conducted.Through a series of tests,we can find that most parameter-free upwind schemes,widely used in practice today,are not applicable to low speeds’simulations.In contrast,SLAU and SLAU2 can give reliable results.Also,the upwind scheme’s influence on the accuracy is stronger than the reconstruction scheme’s influence at low speeds.
