Reflux condensation behavior in a U-tube steam generator with or without noncondensables Original Research Article

A series of reflux condensation experiments on the mid-loop inventory were conducted in the Institute of Nuclear Energy Research integral system test facility with various steam flow rates and noncondensables contents. The focus of this paper is on reflux condensation behavior in a U-tube steam generator with or without noncondensables. In particular, this paper explains the effect of noncondensables on integral system responses, U-tube flow modes, control mechanism for liquid holdup/breakdown, and loop seal clearance/reformation phenomena.