窄矩形通道内过冷流动沸腾汽泡生长模型研究

采用高速摄影的方式，对不同系统压力条件下窄矩形通道内汽泡生长过程进行了可视化实验研究，分析了回路系统压力、主流过冷度、壁面过热度、主流速度等热工参数对汽泡生长的影响，并在Zuber公式的基础上建立了可满足不同实验工况的汽泡生长模型。结果表明： Ja 、Bo、Re和无量纲温度θ可较为全面地描述热工参数和流动参数对汽泡生长的影响，在其他条件相同的情况下，汽泡生长指数拟合曲线的K和n值随压力的升高明显减小；θ越大，汽泡的生长时间和所能达到的最大直径越小；在给定的参数范围内模型结果与实验结果符合较好，但由于低压条件下汽泡直径变化的随机性更强，所以模型结果与个别低压实验数据的相对误差较大。

Experimental Study on Bubble Growth Model of Subcooled Flow Boiling in Narrow Rectangular Channel

By using a high speed camera, a visual investigation of vapor bubble growth under different system pressures in narrow rectangular channel was performed. The influences of system pressure, bulk subcooling, wall superheat and bulk velocity on bubble growth were analyzed. Bubble growth model which could meet different experimental conditions was established based on the Zuber model. The results show that Ja, Bo, Re and non-dimensional temperature θ can describe the impact of the thermal parameters and flow parameters on bubble growth comprehensively. The exponential coefficients of K and n decrease with increasing system pressure; bubble growth time and maximum diameter decrease with increasing θ. It is proved that the model correlates with the experimental data very well. As the bubble diameters are stochastic intensely under low pressure, the relative errors between the model predicted values and experimental data under low pressure are relatively large.