文献类型：期刊文献

英文题名：Numerical and experimental study of the transient conjugate heat transfer and fluid flow of passive residual heat removal heat exchanger

作者：Liu, Yanbin[1];Mu, Zhaozhang[1];Wang, Xuesheng[1];Meng, Xiangyu[1];Yuan, Yuyang[1];Cao, Jiaming[1]

机构：[1]East China Univ Sci & Technol, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China

年份：2022

卷号：181

外文期刊名：INTERNATIONAL JOURNAL OF THERMAL SCIENCES

收录：;EI(收录号：20222712317104);WOS:【SCI-EXPANDED(收录号:WOS:000819441600002)】；

语种：英文

外文关键词：PRHR HX; Initial stage; Transient characteristics; Conjugate heat transfer; Fluid flow

摘要：The transient heat transfer performance of passive residual heat removal heat exchanger (PRHR HX) with C-tube bundle directly influences nuclear reactor safety under accident condition. This paper presents an investigation of transient conjugate heat transfer and fluid flow phenomena and characteristics of scaled-down single C-tube submerged in water tank under atmospheric pressure at the initial period before saturation pool boiling occurs. Empirical calculation model, experimental setup and numerical model were established separately, and both numerical and experimental studies were carried out. The distributions of tube outlet temperature and water temperatures at horizontal and vertical monitoring points in tank were obtained. Detailed comparisons of the results show good agreements. Also, the change tendencies of heat flux, heat transfer coefficients and heat load were analyzed. The fluctuation of heat flux along normalized length from tube inlet firstly increases but finally tends to keep stable with the change of temperature difference and transformation of heat transfer mechanism. The heat transfer coefficient inside tube shows a slight downtrend along normalized length from tube inlet, but the heat transfer coefficient outside tube shows obvious change in the transient process. The total heat load continuously decreases with time. Furthermore, the volume fraction of vapor is relatively low during the sub cooled boiling period. The two-phase flow enhances the agitation in water tank and the fluid velocity near tube outside wall is much larger.