MHD turbulent flow with buoyancy by DNS

S. Satake¹ - K. Sone¹ - A. Sagara² - T. Kunugi³

¹ Department of Applied Electronics, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, Japan
² Fusion and Advanced Technology System Division, National Institute for Fusion Science, 322-6 Oroshicho, Toki 509-5292 Japan
³ Department of Nuclear Engineering, Graduate School of Engineering, Kyoto University, Yoshida, Sakyo, Kyoto 606-8501 Japan

Abstract
Direct numerical simulation (DNS) for the low Pr number fluid flow of turbulent heat transfer with a buoyancy effect has been carried out under a magnetic field in a spanwsie direction. The result is compared with the wall-normal one. The buoyancy effect and the magnetic direction are considered for some statistic data: mean temperature, turbulent heat flux and temperature variant. The Prandtl number was 0.06. The magnetic field at \Ha = 12.0 in a wall-normal direction and at \Ha = 12.0 in a spanwise direction taken from the electric potential equation was applied to a constant magnetic field. Grashof numbers were 4.8 ×10⁶. The Reynolds number for the channel flow based on friction velocity, viscosity and channel half-width was set to be constant as \Rn _τ = 150. Consequently, the thermal efficiency is reduced in the magnetic direction. That is, the thermal reduction by the magnetic field in the spanwise direction is less than that in the wall-normal direction. Tables 1, Figs 6, Refs 1.