A numerical study of convective heat transfer from a blunt plate at low Reynolds number

✍ Scribed by H. Kazeminejad; M. Ghamari; M.A. Yaghoubi

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 762 KB
• Volume: 39
• Category: Article
• ISSN: 0017-9310
• DOI: 10.1016/s0017-9310(96)85011-3

✦ Synopsis

The formulation and numerical investigation ofconvective heat transfer from a two-dimensional blunt rectangular plate is presented. The transformed governing equations in terms of vorticity, stream function and temperature were solved numerically using an efficient finite volume method. A number of interesting features of the flow and heat transfer fields resulting from the leading edge separation are presented in detail. Results including the distribution of friction coefficient and the local Nusselt number were obtained for a range of low Reynolds number. It was found that the physics of the flow and heat transfer changes significantly due to leading edge separation. It was observed that at a Reynolds number, based on plate thickness, of 100 a small separation bubble develops downstream from the leading edge and increases in size in both upstream and downstream extent with an increase in Reynolds number. The leading edge of the bubble reaches the front of the plate at a Reynolds number of 125. The trailing edge continues to move downstream with increasing Reynolds number. reaching a streamwise length of six plate thicknesses at a Reynolds number of 325 and the size of the bubble (or reattachment length) is a linear function of Reynolds number. These findings are consistent with previously published experimental results. The effects of leading edge separation on the local Nusselt number are found to be rather insignificant until the Reynolds number is increased to 225. At Re = 225, the local Nusselt number along the plate varies significantly, and a local minimum in the Nusselt number is found inside the separation bubble and a local maximum near reattachment. Also shown for comparison is the variation of local Nusselt number with distance along the plate for the forced convective laminar boundary layer over a thin plate.