Abstract
Nuclear reactors may be inclined when working on an ocean going floating platform. For this reason, the numerical study of the 3×3 rod bundle channel is carried out in order to explore the flow resistance characteristics under inclined conditions. Due to the structural characteristics of the rod bundle, this paper considers the tilt of two different cases with different inclination angles, and studies the laminar region, transition region and turbulent region flow characteristics. It is found that the inclination has no effect on the frictional resistance coefficient of the rod bundle in the transition region and the turbulent region, and only affects the laminar region at low Reynolds number. Such low Re laminar flow conditions will not occur during the normal operation of the reactor but may happen under accident conditions. Therefore, the flow in the rod bundle channel under laminar flow conditions is studied in detail. It can be shown that reversed flow happens due to thermal stratification under inclined conditions in the laminar region with quite low fluid velocity. The reversed flow is the main cause of the change in flow resistance in the rod bundle channel under inclined condition.
