|
ARTICLE:
H. Nakaharai
Kyushu University, Japan J. Takeuchi
University of California, USA T. Yokomine
Advanced Energy Engineering Science, Interdisciplinary Graduate School of Engineering Science, Kyushu University, Kasuga-kouen 6-1, Kasuga, Fukuoka 816-8580, JAPAN Tomoaki Kunugi
Dept. of Nuclear Engineering, Kyoto University, Sakyo, Kyoto 606-8501, JAPAN S. Satake
Tokyo University of Science, Japan N. B. Morley
University of California, USA M. Abdou
University of California, Los Angeles, USA
ABSTRACT The temperature distribution and Nusselt number (Nu) for high Prandtl number (Pr) turbulent pipe flow through the uniformly heated tube are measured. The objective of this study is to clarify the effect of MHD force on the heat transfer of potassium hydroxide (KOH) aqueous flow. The KOH aqueous flow is a stimulant of the molten salt flow such as FLiBe ((LiF)2-BeF2)as a candidate coolant of fusion reactor. Compared to the studies on heat transfer mechanism of liquid metal, there is a lack of data about that of high Prandtl number fluid for design of MHD devices. Therefore, it is very important for fusion R&D to estimate accurately the effect of magnetic field on heat transfer characteristic related to turbulence modulation.
When the transverse magnetic field is applied, the steep temperature gradient is observed in the near-wall region because of transition to the Hartmann flow which has a steep velocity gradient near the wall. Additionally, suppression of the temperature fluctuation is observed in the near-wall region. The mechanism of suppression is conjugated in connection with turbulence suppression due to the magnetic field by the aid of Direct Numerical Simulation (DNS) results[1][2] already published. As a result, local Nusselt number for turbulent pipe flow decreases 25% at Ha=15, Re=5000, and 15% at Ha=15, Re=20000 from the values without magnetic field.
 download article
EXP-17 pages
« Previous article
Next article »
|
