水下排气速度与温度场的气液两相流数值模拟

Numerical Simulation of Exhaust Velocity and Temperature Field Using Gas-Liquid Two Phase Flow Model

水下航行器发动机排放的高温废气进入海水中热特征明显,研究水下排气的速度与温度场对控制其热特征有重要的理论和应用价值;建立水下排气的质量、动量和能量守恒方程,采用气液两相流混合模型和k-ε紊流模型,利用有限体积数值计算方法,对水下排气的速度场和温度场进行了研究;研究结果表明:在温度均匀的海水中水下排气羽流浮升时,气相速度和温度不断减小,每一个纵截面都存在一个速度和温度最大的中心区域,中心区域的形状由圆形逐渐发展成马蹄形;在水平截面上气相速度场和温度场的区域类似于"流星状",存在明显的速度和温度梯度,与气相速度场相比,温度场的发展区域比速度场窄。

The high temperature exhaust gas of underwater vehicle engine has significant thermal character-istics. The research of velocity and temperature field of underwater exhaust has important theoretical and application value to control the thermal characteristics of underwater vehicle. In this paper,the mass,mo-mentum and energy conservation equations were built for underwater exhaust. Based on the mix model of gas-liquid two phase flow and turbulent model,the velocity and temperature field of underwater exhaust were studied using the finite volume numerical method. The results show that the speed and temperature of gas phase are falling while the underwater exhaust plume rose in the uniform temperature of the sea water. There is a maximum velocity and temperature area at the each longitudinal cross section and the shape of the central region gradually developed by circular into a horseshoe. The gas phase velocity field and tem-perature field of horizontal section area are similar to the meteor and there is the apparent velocity and tem-perature gradient. The developing region of temperature field is narrower than that of velocity field.