### Flow Resistance Measurement of Helical Tube of HTGR Once Through Steam Generator

LI Xiao-wei;ZHAO Jia-qing;WU Xin-xin;LUO Xiao-wei;HE Shu-yan

1. Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing 100084, China
• Online:2015-05-20 Published:2015-05-20

### 高温气冷堆螺旋管式直流蒸汽发生器螺旋管流动阻力测量

1. 清华大学 核能与新能源技术研究院，先进核能技术协同创新中心，先进反应堆工程与安全教育部重点实验室，北京100084

Abstract:

A measuring system using compressed air as the working fluid was built in order to verify the flow resistance uniformity of the helical tubes of the experimental assembly for the high temperature gas-cooled reactor (HTGR) steam generator. The influence of the compressibility of compressed air on the measurement accuracy was carefully discussed. Two data reduction methods with linear average and integration were proposed, and the accuracies of the two methods were compared. Acceleration pressure drop should also be considered during data reduction, and its influence was analyzed under different working conditions. The accuracy and repeatability of the measuring system were first verified using a smooth straight tube and corresponding correlation. Then the flow resistances of the 9 helical tubes of the 5th layer of the experimental assembly were measured. The results show that the maximum relative deviation of friction factor among the 9 helical tubes is 5%. The main cause of the deviation comes from the deviation of the tube inside diameters. The flow transition Reynolds number of helical tubes is different from that of straight tubes. The flow transition Reynolds number of the 5th layer helical tubes of the experimental assembly is about 6000.