受限共轴射流的湍流混合过程数值模拟

本文以下Ｓｔｉｒｌｉｎｇ发动机引射管设计为研究对象，对亚声速受限共轴射流中的两种气体混合过程，用数值模拟方法求解了轴对称雷诺平均Ｎ－Ｓ方程组。提出的一种改进的显式有限体积法，包括基于网格角点的具有高分辨的中心／迎风ＱＵＩＣＫ算法，四阶人工耗散、局部时间步长和隐式余数光滑技术的应用。为加速收敛，采用一种类似于总焓阻尼的方法，引入质量流量阻尼和气流中化学组份质量分数阻尼，以快速获得足够近似的解，适合工

A Numerical simulation for Turbulent Mixing Confined Coaxial Jet Flow

A technique based on an axisymmetric three-dimensional flow model has been developed for solving a class of subsonic ejector designs,that the primary flow oxygen is supplied via the ejector nozzles is used to develop a secondary flow of exhaust gases which has given off their heat to the Stirling engine heater. The mixing with turbulent confined jets is examined, a computer program has been written to solve the problems of subsonic ejector designs and the axisymmetric Reynolds-averaged Navier-Stokes equations. Turbulence is modeled using an algebraic turbulence model. An improved finite volume formulation involving a hybrid central/upwind QUICK differencing, fourth-order artificial dissipation,local time stepping and implicit residual smoothing are used. An efficient acceleration technique is developed based on the conservation damping including the enthalpy damping,mass flow damping and the sum of species density fraction damping, show that enhances substantially its computing efficiency.