中文摘要：

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。

英文摘要：

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.