Numerical analysis of MHD flow structure behind a square rod

摘要

In a liquid blanket system, the large MHD pressure drop for liquid lithium and/or LiPb makes it difficult to remove high heat load. Since the MHD pressure drop is proportional to the flow velocity, it is necessary to remove the high heat load under low velocity conditions. Meanwhile, in case of molten salt Flibe, which is a high Prandtl number fluid, it is also important to enhance the heat transfer performance. In this study, MHD flow structure behind a square rod inserted in a parallel channel to enhance the heat transfer is simulated numerically to clarify the interaction between the flow structure and the magnetic field by using a low-Reynolds number k—ε turbulent model and including MHD effects. The laminar flow analysis indicates that the disappearance of twin vortices and the change of the Karman's vortex street to the twin vortices occur around a Ha/Re_h, ratio of 0.7 and 0.07-0.09, respectively. The turbulent flow analysis confirms that installing the rod near the heating wall contributes to enhancing the heat transfer even in the presence of a magnetic field, although the turbulent kinetic energy decreases with increasing Hartmann number.