矩形窄缝通道临界热流密度数值预测

Numerical Prediction of Critical Heat Flux in Narrow Rectangular Channels

利用已有的实验数据对Weisman模型和Kwon模型的计算结果进行计算与分析。结果表明:2套模型计算偏差分布趋势相似,但Kwon模型的分散度较小,精度更高。对于矩形窄缝通道,已有的汽泡壅塞模型预测精度较差;不宜将汽泡壅塞模型直接用于矩形窄缝通道。结合矩形窄缝通道自身的特性对其中的Kwon模型进行了拓展。改进后的模型具有良好的预测精度且消除了系统性偏差。

Results calculated by the Weisman model and Kwon model are compared and analyzed based on the existing experimental data points.It reveals that the two models have similar tendency for the CHF ratio distribution while the Kwon model has little scattering thus is more accurate.Since both the existing bubble crowding models predict CHF in narrow rectangular channels with poor accuracy,they are not pro-posed to be used for NRCs directly.Considering the characteristics of a narrow rectangular channel,the Kwon model is modified and extended.The improved model has better prediction accuracy and eliminates the systematic deviation from the experimental results.