Entrainment at T-junction: A review work

The T-junctions are widely used in industry, such as the joint between hot leg and Automatic Depressurization System Stage Four (ADS-4)/Passive Residual Heat Removal (PRHR)/surge pipeline in AP1000 plant, header-feeder geometry of CANDU reactor, complex piping systems in the water and petroleum processing and so on. In the nuclear plant accident analysis, the T-junction entrainment is fairly closely linked with the water volume of reactor and reactor safety. Many researchers have conducted the experimental and theoretical research on the generation process, mechanism, influencing factors and modeling of entrainment. Research directions of entrainment at T-junction are multifarious, so a review work is necessary. This paper describes a comprehensive literature review of entrainment at T-junction. Based on different geometric structures of T-junction, detailed summarizations and reviews on the present entrainment phenomena, entrainment models and scaling analysis are performed. Conclusions and further research directions on entrainment at T-junction are proposed. (C) 2013 Elsevier Ltd. All rights reserved.