Numerical analysis of mercury cavitation in MW-scale spallation neutron source system

We are developing a new numerical analysis method for elucidating and predicting the cavitation phenomena in mercury, which make a controversial impact on the development of the MW-scale spallation neutron source systems. The method is a unified methodology for liquid-gas two-phase problem based on the Cubic Interpolation Volume/Area Coordinates (CIVA) method. Since the Combined Unified Procedure (CUP) method is used for basis algorithm and the finite volume method for discretization, the method enables the numerical analysis of multi-phase flow in technologically complex systems. With the aim of the cavitation analysis, the method introduces the following two methods into the code: a generalized equation of state, which unifies the liquid and gas equations of state, and a model that can represent a pressure change caused by the phase change. We analyze the cavitation problem in mercury and compare the results with the Rayleigh-Presset theoretical solution