Instabilities and Nonlinear Transition of High-speed Shear Flow in Shallow Waters

摘要：

　　The nonlinear transition from instabilities of high-speed shear flow is formation of shocklets and radiation of gravity waves.Numerical simulations of the shear ow must be able to capture the velocity and depth discontinuity across the shock waves and allow the waves to radiate from the instabilities to escape without reection at the boundary of the computational domain.A fth-order WENO interpolation scheme is used to manage the spurious numerical oscillations in the present simulation of the high speed shear flow.The advance in time is by a fourth order Runge-Kutta method.A small disturbance is introduced to a jet-and-wake like hyperbolic secant velocity prole.The fractional growth of the amplitude of the disturbance is determined directly from the numerical simulations.The fractional growth rate of the instabilities for a range of convective Froude numbers varying from Frc = 0.05 to 4.0 is determined directly from the numerical simulations.In the limiting case of the incompressible shear ow when the convective Froude number approaches zero,the numerical simulation result is in perfect agreement with the linear stability analysis obtained using the classical normal mode approach.

关键词： Shear-Flow Instabilities High-speed Shallow Flow Shallow Water Equations Gravity-Wave Radiation WENO Interpolation Scheme

作者: Tao Wang Vincent Chu

作者单位: Department of Civil Engineering and Applied Mechanics, McGill University,Montreal,QC H3A 0C3, Canada

会议类型: 国际会议

会议名称: The 8th International Conference of Computational Fluid Dynamics, (ICCFD8)(第八届国际计算流体力学会议)

会议地点: 成都

会议语种:英文

页码: 1-10

在线出版日期: 2014-07-25（万方平台首次上网日期，不代表论文的发表时间）