Flow Behavior Analysis of the Inlet Plenum with Narrow Type Flow-skirt using CFD code

Application of a flow-skirt to the conceptual design of a new research reactor has been considered to reduce the flow induced vibration of fuel assembly. CFD analysis shows that the flow-skirt may suppress the vortex generation at the inlet plenum, which is expected to contribute a lot in decreasing the vibration of the fuel assembly. Because the flow skirt considered from the previous research was large in diameter and the holes were concentrated on lower side of flow skirt, it lead to have large space, the vortices rotating on the vertical direction occured. To complement like this weak point, CFX analysis has been performed to find out flow characteristic from the inlet plenum equipped with the narrow type flow-skirt