Design and Analysis of Separate Heat Pipe-based Passive Residual Heat Removal System for HTR-PM

The high-temperature gas-cooled reactor pebble-bed module (HTR-PM) is a promising advanced nuclear reactor. The passive residual heat removal system is an indispensable safety system guaranteeing the inherent safety of HTR-PM. This study presents a novel design of a separate heat pipe passive residual heat removal system for HTR-PM. The effects of the inlet air temperature, condensation area, air cooling tower height, and height difference between the evaporator and the condenser are systematically investigated. The results demonstrate that the system can effectively handle maximum residual heat removal capacity under accident conditions. Additionally, the study explores the feasibility of condenser miniaturization, revealing that a 70% reduction in size is achievable. The steady-state operation is also calculated based on the optimal design scheme. The outcome indicates that it is possible and advantageous to miniaturize the condenser to prepare and operate the separate heat pipe-based passive residual heat removal system. These findings present new opportunities for miniaturization and mobilization of the passive residual heat removal system for the high-temperature gas-cooled reactor. Further experiments should focus on implementing this strategy on small-scale separate heat pipe heat removal systems. (authors)