The RCCS Thermal Analysis during the Station Blackout Accident of RDE

Abstract

Abstract RDE is designed based on HTGR technologies; it has an active, passive and inherent safety system. Defence in depth philosophy is conducted. The heat transferred from the reactor vessel to the structure of the containment is equipment in the RDE has a name is a reactor cavity cooling system (RCCS). During normal operation and protecting the reactor containment structure in the event of failure of all active cooling systems, the RCCS designed to take fulfill this role by preserving the vessel reactor under the maximum allowable temperature. Concerning heat dissipation design, RCCS assessment and resolution are considered as major factors in determining the maximum power level of heat dissipation. Active and passive mode is the equipment on RDE RCCS. This paper discusses the calculation of RCCS thermal analysis during the station blackout (SBO) accident. SBO occurred and the heat removal is conducted by RCCS when all of the active cooling systems were failed. Conditions will be safe if the RPV temperature must be maintained below 65°C. There is no electricity from diesel generator supplied to the primer compressor, it will the SBO accident. The methodology used is based on the calculation mathematical model of the pebble bed modular reactor heat transfer capability of the RCCS in the passive mode. The passive mode works during the failure of active mode, and the heat is released through the cavity by natural convection. The RCCS is capable to withdraw the heat at 50.54 kW per hour and keep the reactor pressure vessel temperature below 65°C at normal operation and below 125°C during the station blackout.