Behavior of numerical solution obtained using iterative method under III-posed conditions

A two-fluid model is often used in analyzing two-phase flow phenomena of a nuclear power plant. It is well known that obtaining a numerical solution using the two-fluid model is difficult because of the ill-posedness of the equation system itself. The present paper shows the effect of the ill-posedness on the numerical solution obtained using an iterative method, which is often used in the current typical computational fluid dynamics program. It also shows the behavior of the numerical solution of TRAC code under ill-posed conditions. (author)