NUMERICAL STUDY OF LAMINAR NATURAL CONVECTION IN A FINNED ANNULUS: LOW ISOTHERMAL BLOCKS POSITIONS

Natural convection in a fi nned concentric annulus fi lled with air is numerically simulated, using the centered fi nite difference method if the alternating direction implicit scheme is taken into account. Two isothermal blocks are attached to the inner cylinder and placed symmetrically in the low section of the annulus. The radius ratio, as well as the dimensionless width and height of the blocks, are kept constant. The effect of the Rayleigh number Ra varying between 1000 and 10,000 on the fl ow pattern and heat transfer rate is discussed. It is shown that unicellular and bicellular fl ows are observed, and the blocks increase the overall heat transfer rate for the studied range of Ra. 
   
Author:  S. Touzani, A. Idrissi, A. Cheddadi, and M. T. Ouazzani
Keywords:  natural convection, isothermal blocks, concentric annulus, fi nite difference, heat transfer enhancement.
Page:  1064