Experimental study on heat transfer characteristics of separated heat pipe with compact structure for spent fuel pool

A separated heat pipe radiator with compact evaporator section and condenser section was manufactured for the cooling of spent fuel pool. The cold start process shows that the heat pipe can be started smoothly at a given temperature difference. And the effects of various external working conditions on heat transfer capacity and temperature instability of heat pipe are studied, including intake air volume, intake air temperature, and inclination angle. The results show that the radiator can dissipate about 4 kW in the design working condition, and its heat dissipation capacity is further improved in the inclined state. Under the most unfavorable conditions, the water temperature didn't exceed 90celcius, and the temperature distribution inside the water tank was uniform. This separated heat pipe radiator has a positive significance for the decay heat removal and hot spot elimination of the spent fuel pool.