Numerical Simulation of Unsteady Flows Based on Gas-kinetic Unified Algorithm

摘要：

　　Transport properties of one- and two-dimensional unsteady flows are analyzed by the Gas-Kinetic Unified Algorithm (GKUA) from rarefied transition to continuum.A new unsteady flow solver is developed by numerically computing the Boltzmann-Rykov Model equation involving the effect of rotational energy.Moment quadrature to the molecular velocity distribution function by rotational degree of freedom is introduced.And reduced velocity distribution functions are used to simplify governing equations of one- and two-dimensional flows.By employing discrete velocity ordinate method and numerical integral technique in velocity space,simultaneous equations for reduced velocity distribution functions at each discrete velocity point are obtained from the kinetic model equation.Time-explicit finite difference method is applied to solve these one- and two-dimensional model equations for diatomic gases,and then unsteady movement processes of one-dimensional shock tube flow and two-dimensional flow past a cylinder with different Knudsen numbers are considered.It is shown that the GKUA solver is competent for simulating the unsteady flow problems covering various flow regimes.Rarefied effect is also analyzed for flows in the shock tube,and movement rules and evolvement processes for interaction of shockwaves are studied in unsteady flows from rarefied transition to continuum.

关键词： Unsteady Flow Boltzmann Model Equation Gas-kinetic Unified Algorithm Discrete Velocity Ordinate Method

作者: Wu J.L. Li Z.H. Peng A.P. Jiang X.Y.

作者单位: China Aerodynamics Research and Development Center,Mianyang Sichuan 621000,China China Aerodynamics Research and Development Center,Mianyang Sichuan 621000,China;National Laboratory

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: 1-13

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）