Application of the adiabatic spatially dependent reactor kinetics method to voided pressurized water reactors

Computer simulations were conducted for experiments concerning an ex-core axial string of epi-cadmium neutron detectors acting as a coolant density and level gauge. Static transport calculations were performed for experiments conducted with the Pennsylvania State University TRIGA reactor with a downcomer simulator installed. This simulated the response of an ex-core neutron level gauge to varying downcomer voiding along. Static transport calculations were also performed with the TMI accident boiloff scenario, simulating the response of an axial string of three ex-core detectors. Two other TMI simulations, with varying downcomer voiding with the core full and the core empty, were also performed, which were compared to the TRIGA experimental results. Spatially dependent reactor kinetics simulations, using transport theory, were conducted for the LOFT large break tests L2-5, and LPO2-6. In these calculations, the axial neutron detector responses to a known spatially dependent voiding history were simulated. The static transport calculations were performed with the two-dimensional transport code DOT. The spatially dependent reactor kinetics calculations were performed using the adiabatic reactor kinetics method using reactor kinetics code and the transport code DOT. The adiabatic method of spatially dependent reactor kinetics was shown to give reasonably accurate simulations of the LOFT experiments