Thermal Fluid-Structure Interaction Analysis for the Upper Structure of LMFRs

Abstract

This paper describes a thermal fluid-structure interaction analysis code FLUSH that calculates both thermalhydraulics and thermal structure response at the same time. This code has been developed to evaluate the thermal responses of the upper structures of LMFRs, using two different analysis codes of α-FLOW and FINAS. The heat flux on the boundary surface of the fluid region and the temperature on the boundary of the structure region are exchanged in every iterative cycle as the new boundary conditions, and finally the unified thermal fields are calculated. The different mesh method and the detail thermal radiation model were also developed to apply for the large scale models.The 2-D model of the basic experiment for the cover gas thermal-hydraulics was calculated to verify this iterative method. The calculated average temperature on the boundary agreed well with the experimental results. The 3-D large scale models of the out-of-pile experiment for MONJU shield plug were also calculated to verify this method. The calculated temperature both in the annulus and the shield plug agreed well with the experiments. These studies showed that this iterative method of FLUSH was very effective for the predictions in the strong coupled thermal fields.

Numerical Simulation of Aerosol Behavior in Turbulent Natural Convection

“…Only a few studies were carried out to evaluate the heat transfer of the cover gas as an equivalent single gas. 5) These approaches are valid for the overall estimations of the heat transfer, but it is difficult to evaluate their characteristics in detail and find out the control methods for the complex transport phenomena. On the other hand, the aerosol behavior in the sodium leakage accidents were numerically evaluated.…”