Air-Cooler Structure Optimization of HTGR Passive Cavity Cooling System

Air cooler is an important equipment of HTGR passive cavity cooling system. Structure optimization is necessary to improve the flow uniformity. In this work, the flow distribution characteristics are numerically investigated for four air coolers, including the Z-type, U-type, semi-Z-type and central-type arrangements. By comparison, the flow distribution of central-type arrangement is more uniform than that of other arrangements, with the non-uniformity coefficient reduction by 73%. Moreover, the phenomenon of static pressure recovery also appears in the distribution headers of semi-Z-type and central-type arrangements. Tube-side water flow in the central-type arrangement can be regarded as the parallel connection of two U-type arrangements. Central-type arrangement reports a symmetrical structure design, as the promising optimization for air cooler.