The US NRC Advanced Gas Reactor Evaluator (AGREE)

Abstract

A Prismatic Module Reactor (PMR) core fluids model has been developed in support of the US NRC Next Generation Nuclear Plant (NGNP) evaluation model. The PMR core fluids modeling relies on a subchannel approach in which the primary coolant flowpath through the core region and vertical in-core and ex-core gaps can be modeled as individual subchannels. These subchannels are connected together to represent a three dimensional reactor. An initial validation calculation has been performed using data available in literature for bypass flow. The predicted bypass flow was within 2.6% of the value reported in the literature. Further verification and validation is awaiting the completion of the coupling of the fluids model with a triangular solid heat conduction model.