Numerical Study and Sensitivity Analysis of PRHR HX Transient Heat Transfer Performance

Natural convection in AP600 （American Passive Advanced Pressurized Water Reactor） passive residual heat removal heat exchanger （PRHR HX） is numerically studied with FLUENT. Numerical investigation using standard k-ε model and Boussinesq model is performed. The transient numerical results show that the heat transfer performance of the PRHR HX and IRWST are consistent with AP600 experimental results. The sensitivity analysis has the following conclusions:a. the effect of baffle position and inlet construction on heat transfer performance is very small and b. with the increase of the number of heat exchanger pipes or the initial temperature of water in IRWST,the heat transfer will be enhanced.