EXPERIMENTAL STUDY ON CHUGGING CONDENSATION REGIME OF STEAM DIRECT CONTACT CONDENSATION IN WATER FLOW IN A TEE JUNCTION

摘要

The phenomenon of direct contact condensation (DCC) is encountered in both the nuclear industry and conventional industry and it is intimately associated with safety operation of relevant equipment. Studies on steam jet discharged directly into a stagnant water pool have been studied extensively; however, they are sparse for direct contact condensation of steam in sub-cooled water in pipes. In this paper, the experiments were performed to study the direct contact condensation of low mass flux saturated steam discharged into sub-cooled water flow in a Tee junction. By using high-speed camera, we investigated chugging condensation characteristics including two-phase interface movements. It is can be seen from the experiment results that, for chugging, steam plume and surrounding sub-cooled water undergo the following process: steam plume grows to the maximum, then steam plume becomes smaller due to condensation, and finally, water enters the vertical branch pipe and steam ejects from the vertical branch pipe again.