The thermal striping can generate fast random temperature fluctuation in fluid and will transfer it to structure. It will induce high cycle thermal fatigue in several components particularly in central column and should be concerned is for Sodium Cooled Fast Reactor(SFR). However, the recent research focus on the flow and temperature characteristics of fluid. The transient temperature distribution inside the solid structure is not comprehensive enough, which is important for analyzing cyclical thermal stresses and eventually the fatigue cracks of structure. In this study, coaxial jet model and large eddy simulation(LES) were used to simulate the fluid flow of upper plenum of SFR. The transient temperature distribution inside structure were studied by Heat-fluid-solid coupling analysis. The results show that thermal fluid-solid coupling simulation is feasible and accurate to analyze the temperature distribution of structure. The temperature fluctuation from the fluid to the structure surface is significantly attenuated. It can only be transferred to limited depth inside the structure. The results contribute to the high frequency thermal fatigue life prediction of nuclear component.
Keywords thermal striping, transient temperature, large eddy simulation, coaxial jet model, central column