不同系统压力下汽泡生长特性及压力影响机理分析  

Investigation on Characteristics of Bubble Growth and Effect of System Pressure on Bubble Growth

作　　者：陈德奇[1] 潘良明[1] 袁德文[1] 黄彦平[2] 

机构地区：[1]重庆大学动力工程学院,重庆400044 [2]中国核动力研究设计院,成都610041

出　　处：《核动力工程》2011年第3期63-67,共5页Nuclear Power Engineering

基　　金：国家自然科学基金项目(50406012);中国核动力研究设计院空泡物理和自然循环重点实验室2008年基金资助项目(9140C7101020802);重庆大学211工程3期建设项目(CS-09101)

摘　　要：为了探讨系统压力变化对窄流道内汽泡生长的影响,在不同系统压力(0.1～1 MPa)下采用高速摄像仪对2 mm竖直矩形窄流道内的汽泡生长进行可视化研究。研究表明,发现在0.1～0.3 MPa下汽泡的生长主要在核化点处进行,但在较高压力(ps≥0.6 MPa)时汽泡生长主要是在滑移中进行,汽泡的尺寸也显著减小;由于汽泡行为发生变化,不同系统压力下加热壁面上的换热状况有着很大区别。用拉普拉斯数(La)和时间因子(ξ)分别对汽泡半径和汽泡生长时间进行无量纲化后,无量纲汽泡生长曲线遵循指数曲线变化;指数曲线的系数k随系统压力升高而减小。In order to analyze the effect of system pressure on bubble growth in a narrow channel,a vis-ual investigation on bubble growth under different system pressure（0.1-1 MPa） in a vertical rectangular nar-row channel with 2 mm gap was carried out using the high speed camera.It was found that the bubble was growing at the nucleate site under 0.1-0.3 MPa system pressure;while it was sliding along the heating wall during growing under higher system pressure（ps？0.6 MPa）,and the size was much smaller.The heat transfer on the heating wall is obviously different due to different bubble behavior under different system pressure.After non-dimensionalization of bubble radius and bubble growth time with Laplace number,La,and time factor,？,respectively,the dimensionless bubble growth curve fits the power curve very well,and the coeffi-cient k of the power curve decreases with the increasing of the system pressure.

关 键 词：汽泡生长 系统压力 汽泡滑移 

分 类 号：TL124[核科学技术—核能科学]