垂直加热管内下降两相流瞬态空泡率的数学模型研究

THE STUDY ON TRANSIENT MATHEMATICAL MODEL OF TWO-PHASE VOID FRACTION IN HEATED VERTICAL DOWN-FLOW TUBE

本文提出瞬态垂直下降流动管内两相流空泡率的数学模型和其计算方法，可用来计算介质流量瞬变和加热负荷瞬变时管内各处的空泡率．为了验证模型计算的精确性，在R－12实验台架上进行了空泡率的测量，同样工况下，测量与计算结果相当一致．流量瞬变时的最大平均偏差小于13％，热负荷瞬变时小于15％．由此可认为本模型方法，可用于工程计算，尤其适用于棒束之类的复杂流道．

In this paper a transient mathematical model of two-phase flow void fraction in heated vertical down-flow tube is proposed for the prediction of void fraction in the conditions of transient variation of mass flow rate and heat input. Experment measurement of transient void fraction are also done in a R-12 test loop. The comparisions of predicted and measured values in the same conditions are fairly consistent. The maximum average deviations are less than 13% for the transient mass flow and 15% for the transient heat input. This show the proposed method is available for engineering calculation especially for the complicated ducts as rod-bundles.