A New Computational Tool for the Simulation of Three-Dimensional, Two-Phase Flow and Heat Transfer in Boiling Water Reactors

65016 The design of safer, more efficient boiling water reactor (BWR) fuel assemblies requires a computational tool that is capable of accurately predicting the dynamics of three-dimensional (3-D) multiphase flow and heat transfer phenomena in the fuel bundles. This project will extend the Lattice Boltzmann Method for multiphase flows with emphasis on boiling water phenomena. Phase I will complete the remaining theoretical development for a multiphase Lattice Boltzmann approach capable of simulating water boiling phenomena. An initial prototype software tool will be developed to demonstrate and validate the ability to accurately predict the boiling water two-phase flow characteristics in a simple geometry. Ultimately, capabilities will be added to simulate the complex 3-D two-phase flow and heat transfer phenomena that occur in a BWR fuel bundle, including formation and transport of bubbles, flow regime changes, and coolant interaction with the fuel pins, spacers, and other fuel bundle elements. Commercial Applications And Other Benefits as described by awardee: Commercial BWR vendors should immediately benefit from the technology, but other applications also exist including chemical and industrial processing.