Improved-Delayed-Detached-Eddy Simulation of Cavity-Induced Transition in Hypersonic Boundary Layer
Hypersonic flow transition from laminar to turbulent due to the surface irregularities,like local cavities,can greatly affect the surface heating and skin friction.In this work the hypersonic flows over a three-dimensional rectangular cavity with length-to-width-to-depth ratio,L:W:D,of 19.9:3.57:1 at two angles of attack (AoA) are numerically studied with Improved-Delayed-Detached-Eddy-Simulation (IDDES) method to highlight the mechanism of transition triggered by the cavity.The present approach was first applied to the transonic flow over M219 rectangular cavity.The results,including the fluctuating pressure and frequency,agree with experiment well.In the hypersonic case at Mach number about 9.6 the cavity is seen as open at AoA of -10° but closed at AoA of -15° unconventional to the two-dimensional cavity case where the flow always exhibits closed cavity feature when the length-to-depth ratio L/D is larger than 14.For the open cavity flow,the shear layer is basically steady and the flow maintains laminar.For the closed cavity case,the external flow goes into the cavity and impinges on the bottom floor.High intensity streamwise vortices,impingement shock and exit shock are observed causing breakdown of these vortices triggering rapid flow transition.
Hypersonic flow Transition Cavity Improved-Delayed-Detached-Eddy-Simulation (IDDES)
Xiao Lianghua Xiao Zhixiang Duan Zhiwei Fu Song
Tsinghua University, Beijing, 100084, China
国际会议
The 8th International Conference of Computational Fluid Dynamics, (ICCFD8)(第八届国际计算流体力学会议)
成都
英文
1-19
2014-07-25（万方平台首次上网日期，不代表论文的发表时间）