Natural Convection in Fluid/Porous Region Heated from Below with Conductive Partition

作者：Jang Jiin Yuh^*; Chou Wen Cheng; Leu Jin Sheng

来源：Journal of Thermophysics and Heat Transfer, 2012, 26(2): 367-374.

DOI：10.2514/1.T3660

A numerical study has been made of natural convection in an enclosure heated from below with a conductive partition. The upper and lower regions are filled with pure fluid and a fluid-saturated porous medium, respectively. Two-dimensional Navier-Stokes-equation and non-Darcian models (including inertia, boundary, and convective effects) govern the fluid region and the porous region. The major parameters of the problem are fluid Rayleigh number Ra, partition location height ratio (denoted HR), aspect ratio it, porosity e, conductivity ratio of the partition to the fluid (denoted KR), and conductivity ratio of the fluid/porous matrix to the fluid k(e)/k(f). The results indicate that the partition location and thermal conductivity significantly influence the heat transfer rate. Lower HR (a thinner porous region) and higher thermal conductivity ratio KR possess a higher heat transfer rate and intensify the occurrence of the onset of convection. In addition, high porosity and high effective thermal conductivity in the porous medium can increase the heat transfer rate. The increase of Nu is about 35 similar to 41%, with increase of k(e)/k(f) from 1-5 for porosity ranging from 0.4-0.6.

• 出版日期2012-6