Heat transfer performance of a heat pipe with sintered stainless-steel fiber wick

Stainless-steel heat pipe having sintered stainless-steel fiber wick was proposed for the heat dissipation scenario for special cases such as spent fuel pool cooling in nuclear power plant. While the heat transfer performance is poor at the anti-gravity and zero-gravity cases. In this paper, the effects of fiber type and wettability of working fluid on the heat transfer performance of the stainless-steel heat pipe having sintered stainless-steel fiber wick are studied with the aim to improve its heat transfer performance. It is found the thermal resistance of the heat pipe with turned fiber wick is always smaller than those of the heat pipes with drawn fiber wick because of the micro scale structure on the surface of the turned fiber. Considering the stainless-steel fiber wick is hydrophobic corresponding to water, water-ethanol solution is suggested as the working fluid for the stainless-steel heat pipe in the case that capillary force is necessary to provide enough driving force for working fluid cycle. It is found that the wick made by turned fiber and using water-ethanol solution as working fluid has larger capillary performance factor. The appropriate water-ethanol concentration proportion, from 9:1 to 13:1, is preferred.