Experimental Study on Penetration Length in a Small Size Branch Pipes in Nuclear Power Plant

Abstract

Penetration phenomena in a closed branch pipe connected to a high velocity and high temperature flow in a main pipe were investigated experimentally. The penetration length has been studied with a pipe of 43mm in I.D. where the damages due to the thermal fatigue were reported. The purpose of this study is to expand the data on the penetration length in the smaller pipes. It was found that the penetration length and the period of fluctuation increased with increasing the pipe diameter and the main flow velocity. An empirical non-dimensional correlation on the penetration length in a uniform temperature condition for the pipe inner diameter from 8mm to 43mm was proposed.