湿蒸汽凝结流中自激振荡模式的数值模拟  

Numerical Simulation of Self-excited Oscillation Patterns in Wet Steam Flow with Condensation

作　　者：吴晓明[1] 李国君[1] 李亮[1] 丰镇平[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《动力工程》2009年第8期747-751,共5页Power Engineering

基　　金：国家自然科学基金重点资助项目(50336050)

摘　　要：采用一种基于Eulerian/Eulerian分别描述汽液两相的数值模型,对缩放喷管内的湿蒸汽自激振荡凝结流动进行了数值模拟,并分析了该现象的机理.从空气动力学的角度介绍了稳态和非稳态流动之间的转换过程;从分析各类振荡模式的形成机理出发,结合气动激波的运动规律,解释了在保持喷管进口总压不变的情况下,自激振荡频率随进口过冷度的增大先降低后升高的特性;分析了二次凝结的成因及其激波运动规律,发现位于喷管收缩段的凝结同样能引发自激振荡现象.Based on an Eulerian/Eulerian numerical model for the steam and liquid two-phase flow, the selfexcited oscillation flow of wet steam in a convergent-divergent nozzle was numerically investigated, and the mechanism of the phenomenon was analyzed. From the aerodynamics point of view, the transitional process from steady to unsteady flow was described. Based on the mechanism of different oscillation flows and shock wave kinematics, the flow characteristic was explained that with the increased inlet supercooling and constant inlet pressure, the self-excited frequency of oscillating flow decreases first and then increases. Mechanisms of secondary condensation and shock wave motion were analyzed. In the convergent section of the nozzle, condensation may also cause self-excited oscillation.

关 键 词：湿蒸汽 凝结 自激振荡 激波 数值模拟 

分 类 号：TK262[动力工程及工程热物理—动力机械及工程] O354[理学—流体力学]