Study on heat transfer characteristics of loop-thermosyphon at boiling part

Abstract

Heat transfer characteristics of boiling part under low-pressure is examined experimentally in order to improve thermal performance of loop thermosyphon. Thermal performance of pyramid 2.5mm type is the best among test surfaces when pure water is used as working fluid. By adding surfactant to pure water, thermal performance is futher improved. However, the effect of surface type and surfactant on thermal performance is almost disappear at lowest pressure of 5kPa.