Thermal Hydraulic Analysis of the Convective Heat Transfer of an Air-cooled BWR Spent Fuel Assembly

摘要

Since the reactor accident in Fukushima Daiichi, the vulnerability of spent fuel pools (SFP) is more focused in nuclear safety research. In case of a structural damage of the SFP through an external event with a loss of coolant, the coolability of the spent nuclear fuel is endangered. If the pool is completely drained, the fuel assemblies (FA) are fully uncovered and only cooled by air. A sufficient decay heat transfer depends on the arising air mass flow from the containment through the spent FA from bottom to top (chimney effect). Beside analytical approximations from the U.S. Nuclear Regulatory Commission (NRC) that are partially not publicly accessible only little experimental data about loss of coolant accidents in SFP exist.