Study on improvement of constitutive equations and numerical methods for three-fluid model

The Japan Society of Multiphase Flow*; Special Committee for Examination of Thermohydraulic Analysis Code based on Three-Fluid Model*

The purpose of the present study is to improve a numerical analysis method for multiphase flows based on the three-fluid model. The improvement will be conducted for the following three items; (1)modeling of the multiphase flow, (2)constitutive equations (3)numerical method. A systematic survey was carried out for the aforementioned three items. As a result, a reliable plan for the improvement was proposed. Experimental database for air-steam and air-water two-phase annular flow was also presented in this report, which will be useful for the future improvement of the constitutive equations. As for the numerical method, a method for improving the computational efficiency was proposed. It was confirmed that the CPU time decreases about 95% with the proposed method.