重力热管喷涌不稳定性调控判据

GRAVITY HEAT PIPE SPEWING INSTABILITY REGULATION CRITERION

重力热管内的两相流型对其工作特性有着至关重要的影响。本文借鉴垂直圆管内两相流型转变的实验研究结果和近饱和自由降膜流始发沸腾的观测结论,通过简化分析,给出重力热管蒸发段内由泡状流向弹状流过渡的流型转变判据。在低饱和蒸汽压和高过冷度下,这种流型转变将导致周期性振荡的两相流不稳定性,这就是喷涌不稳定性;因此,流型转变判据也就是喷涌不稳定性调控判据。文中还结合数值计算实例,指出影响流型转变的重要因素。

Two-phase flow patterns on gravity heat pipe have an important influence on working characteristics. The paper uses for reference two-phase flow patterns transformation in avertical pipe experimental research result and observation conclusion of approximately saturable freely-falling film flow departure harbor boiling, through simplified analysis, the paper is given that flow patterns transformation criterion which from the bubbly flow transition the slug flow in gravity heat pipe evaporatior. At the low saturation steam pressure and the high undercooling, this flow patterns transformation will conduce periodic oscillation two-phase flow instability, this is spew instability. Therefore, flow patterns transformation criterion is spew instability regulation criterion. According to numerical calculation example, it is pointed out that effect flow patterns transformation of important factors.