Study of Shock Waves/Boundary Layer Interactions on Hypersonic Intake Flows

• Main Authors: Pin-chian Tseng, 曾品蒨
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/04293377258246163738

碩士 === 逢甲大學 === 航太與系統工程所 === 100 === This paper describes using finite volume method to solve Reynold average Navier-Stokes Equations, simulated a hypersonic intake has a double-ramp compress section. Considering varied geometry to carry out 2-D and 3-D computing simulation of flow field. Computing simulations of the shock wave/boundary layer interaction at the double-ramp and isolator, we have further research about the flow field change result from the 3-D effect. During the research, we test the mesh first, increase the mesh number at the leading edge of the intake, corner between two faces and near wall. We try to use boundary layer mesh, from the result we fine out the boundary layer mesh can effectively reduce mesh number of model without affecting the accuracy of the shock wave simulation. Therefore, we use boundary layer mesh in our computing simulation. About unsteady test, investigate the affect of calculation results with different time step size and time steps, the calculation results show that the time step size is accounted decided of the result, smaller time step size can obtain correct results, but we may cause lengthy computation time if time step size too small. This study further explores the airvent geometry affect of hypersonic intake coupled flow field, the calculated results show the separation point of two ramps corner will delay induced if we increase airvent, and discharge separation bubble induced by the boundary layer smoothly at isolator inlet, improve the flow field in the isolator with shock wave/boundary layer interaction is weakened. The result of 3-D computing simulation show the high-speed airflow will be loss from sides with not consider the sidewall, it can reduce the mass flow entering the engine, 3-D flow field will be improve the phenomenon of loss if we increase sidewall. The corner vortex caused by the sidewall can generate further interaction with separation shock wave, additional shock wave will be induced in coupled flow field of separation bubble.