Influence of power-law index on transitional Reynolds numbers for flow over a semi-circular cylinder

Chandra, Avinash ; Chhabra, R. P. (2011) Influence of power-law index on transitional Reynolds numbers for flow over a semi-circular cylinder Applied Mathematical Modelling, 35 (12). pp. 5766-5785. ISSN 0307-904X

Full text not available from this repository.

Official URL: http://www.sciencedirect.com/science/article/pii/S...

Related URL: http://dx.doi.org/10.1016/j.apm.2011.05.004

Abstract

In this work, the governing partial differential equations (continuity and Cauchy's momentum equations) describing the flow of power-law type non-Newtonian fluids across a semi-circular cylinder (oriented with its curved surface in the upstream direction) have been solved numerically. In particular, consideration has been given to the delineation of the critical Reynolds numbers denoting the onset of flow separation from the surface of the cylinder and the onset of the laminar vortex shedding regime. This information is germane to establish the scaling of the macroscopic characteristics like drag coefficient and Strouhal number on the governing parameters, namely, Reynolds number and power-law index. The present results clearly suggest that the transitional Reynolds numbers show a strong dependence on the type (shear-thinning and shear-thickening) of fluid behavior as well as on the severity of the shear-dependence of the viscosity. With reference to the behavior seen in Newtonian fluids, the flow remains not only attached to the surface up to higher Reynolds numbers, but shear-thinning behavior also delays the onset of the laminar vortex shedding regime. As expected, shear-thickening fluids, of course, display the opposite characteristics.

Item Type:Article
Source:Copyright of this article belongs to Elsevier Science.
Keywords:Semi-circular Cylinder; Flow Separation; Vortex Shedding; Critical Reynolds Number; Strouhal Number; Power-law Fluids
ID Code:78562
Deposited On:20 Jan 2012 12:08
Last Modified:20 Jan 2012 12:08

Repository Staff Only: item control page