Research on optimization of momentum source model to supercritical carbon dioxide flow in wire wrapped rods bundle

Abstract

Wrapped wire is widely used in new reactor core design. The structure of wire wrapped rod bundle is special. Calculation with traditional body fitted grid needs a large number of grids, which requires more computation resources. Simulation of wire wrapped rod bundle with arbitrary wire shape could be carried out on the basis of structured bare rod bundle grids by optimizing the basic mathematical model of momentum source method. Through the simulation of 3 wire wrapped rod bundle experiment, the model adaptability of momentum source method is carried out. Then optimized momentum source method and original momentum source method are compared based on simulation of supercritical carbon dioxide flow and heat transfer in wire wrapped rod bundle with different wire shape. Through comparison with body fitted grid, the improvement of accuracy of optimized momentum source model can be proved. The advantages of optimized momentum source method in improving convergence and saving computation resources can also be illustrated. In conclusion, optimized momentum source method can greatly save the computation resources needed for simulation of wire wrapped rod bundle, and calculated results have more less difference with body fitted grid than original momentum source method.