Numerical Analysis of Turbulent Flow in Subchannels Under Rolling Motion Condition

The influence mechanism of rolling motion on the flowing and heat transfer characteristics of turbulent flow in typical four rod bundles was investigated with FLUENT code. The flowing and heat transfer characteristics of turbulent flow in rod bundles can be affected by rolling motion. The parameters in subchannels under rolling motion condition can be described very well with RSM model. The variation of radial additional force due to the variation of rolling period does not affect on the frictional resistance coefficient, heat transfer coefficient and Reynolds stress. Under rolling motion condition, the frictional resistance coefficient, heat transfer coefficient and Reynolds stress oscillate periodically. However, the occurring time of maximum frictional resistance is not constant, while the maximum heat transfer coefficient occurs when the flow velocity is the maximum.