Abstract
In order to improve the prediction accuracy of the film flow analysis in an extremely narrow channel with roughness, validity and adequacy of turbulence models on the film flow analysis were evaluated. In the present study the extremely narrow channel simulates gap spacing between each fuel rods in a fuel bundle of a reduced-moderation light water reactor. Four kinds of turbulence models are considered : standard k-ε model; modified k-ε model; Reynolds stress model; and large eddy simulation. As for the predicted results by those turbulence models on the generation, scattering and disappearance of droplets a great difference was seen at each other result. The void fraction, axial velocity and turbulence kinetic energy distributions in a narrow channel were estimated, and then, the effect of turbulence models on the liquid film flow behavior and an obstacle was clarified quantitatively.
