CALCULATION OF THE TEMPERATURE STATE OF FUEL ELEMENTS IN A COOLING POND OF POWER BLOCK No. 4 OF BELOYARSK NUCLEAR POWER PLANT IN BEYOND-THE-DESIGN ACCIDENT

The temperature state of the spent nuclear fuel (SNF) of the BN-800 reactor was studied under conditions of a beyond-the-design accident associated with a sudden complete draining of the spent nuclear fuel cooling ponds. The calculations were performed taking into account natural turbulent convection and thermal radiation for various values of residual heat release of the spent nuclear fuel. Two accident scenarios were considered with forced ventilation to the spent nuclear fuel cooling pond and with natural ventilation of the spent nuclear fuel cooling pond, i.e., under conditions of a complete deenergizing of the spent nuclear fuel storage facility. For each of the investigated emergency scenarios, stationary temperature fi elds were obtained in the cooling pond compartment, spent nuclear fuel cans, and spent fuel assemblies, and a conclusion was made about whether the specifi ed maximum permissible fuel element cladding temperature of 800o C was reached or not. Recommendations are given on possible methods for intensifying the cooling of spent fuel assemblies in conditions of a beyond the design accident.
The temperature state of the spent nuclear fuel (SNF) of the BN-800 reactor was studied under conditions of a beyond-the-design accident associated with a sudden complete draining of the spent nuclear fuel cooling ponds. The calculations were performed taking into account natural turbulent convection and thermal radiation for various values of residual heat release of the spent nuclear fuel. Two accident scenarios were considered with forced ventilation to the spent nuclear fuel cooling pond and with natural ventilation of the spent nuclear fuel cooling pond, i.e., under conditions of a complete deenergizing of the spent nuclear fuel storage facility. For each of the investigated emergency scenarios, stationary temperature fi elds were obtained in the cooling pond compartment, spent nuclear fuel cans, and spent fuel assemblies, and a conclusion was made about whether the specifi ed maximum permissible fuel element cladding temperature of 800o C was reached or not. Recommendations are given on possible methods for intensifying the cooling of spent fuel assemblies in conditions of a beyond the design accident.
Author:  E. V. Sadikova, A. A. Pletnev, V. G. Sidorov
Keywords:  spent nuclear fuel, cooling pond, beyond-the-design accident, numerical simulation, heat and mass exchange
Page:  38