Modeling and performance analysis of separate heat pipe containing non-condensable gas for pool-type low-temperature heating reactor

Abstract

The application of separate heat pipe technology in the Passive Residual Heat Removal System (PRHRS) of Swimming Pool-type Low-Temperature Heating Reactor (SPLTHR) can efficiently transfer heat without concerns of working medium leakage and installation difficulties. Since the reactor pool is at atmospheric pressure, the separate heat pipe is required to operate at sub-atmospheric pressure. In this paper, a one-dimensional program code to evaluate the heat transfer performance of a separate heat pipe loop containing non-condensable gas (NCG) is established. On this basis, the effects of some parameters on the system performance are investigated. The results show that the NCG occupies part of the condenser space, weakening the heat transfer performance of the system significantly. Within the calculated range, the presence of NCG can lead a maximum 79% decrease in system's heat transfer rate. For the system's external conditions, the heat transfer rate exhibits greater sensitivity to the water temperature of the pool as compared to the air temperature. Moreover, an increase in the air velocity tends to diminish the strengthening effect in system heat transfer capacity gradually. The obtained analytical results can provide reference for practical engineering application.