ARTICLE:

• LARGE EDDY SIMULATION OF TURBULENT HEAT TRANSFER IN A DIMPLED CHANNEL  download article

Y. O. Lee
Korea Power Engineering Company, Yongin, Korea

J. Ahn
Korea Institute of Energy Research, Daejeon, Korea

J. C. Song
Seoul National University, Seoul, Korea

Joon Sik Lee
School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1. Sillim-dong Gwanak-gu .Seoul 151-742 Korea

ABSTRACT

Large eddy simulation (LES) data are presented which describe flow and heat transfer characteristics in a dimpled channel. The ratios of dimple depth and channel height to the dimple print diameter are 0.2 and 0.5, respectively. The bulk Reynolds number is 20,000. Dimples are arranged on a side of the channel in a staggered array. LES predicts quantitatively well the local Nusselt number distribution, which has not been reproduced by RANS or other turbulence models. Heat transfer rate is enhanced because all three components of velocity fluctuations are intensified along the shear layer above the recirculation bubble in the dimple. The u_rms is locally maximized on the wall around the downstream rim of the dimple while the w_rms does around the reattachment point. The instantaneous flow and thermal fields show that the heat transfer in the dimpled channel is enhanced by the vortices generated at the shear layer.

 download article

TRB-24 pages

« Previous article         Next article »