Steady forced convection heat transfer from a heated circular cylinder to power-law fluids
International Journal of Heat and Mass Transfer 50 (2007) 977–990 www.elsevier.com/locate/ijhmt Steady forced convection heat transfer from a heated circular cylinder to power-law fluids
Ram Prakash Bharti a, R.P. Chhabra a,*, V. Eswaran b a b
Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, India
Department of Mechanical Engineering, Indian Institute of Technology, Kanpur 208016, India
Received 12 January 2006
Available online 12 October 2006
Abstract
Forced convection heat transfer to incompressible power-law fluids from a heated circular cylinder in the steady cross-flow regime has been investigated numerically by solving the momentum and thermal energy equations using a finite volume method and the QUICK scheme on a non-uniform Cartesian grid. The dependence of the average Nusselt number on the Reynolds number (5 6 Re 6 40), power-law index (0.6 6 n 6 2) and Prandtl number (1 6 Pr 6 1000) has been studied in detail. The numerical results are used to develop simple correlations as functions of the pertinent dimensionless variables. In addition to the average Nusselt number, the effects of Re, Pr and n on the local Nusselt number distribution have also been studied to provide further physical insights. The role of the two types of thermal boundary conditions, namely, constant temperature and uniform heat flux on the surface of the cylinder has also been presented.
Ó 2006 Elsevier Ltd. All rights reserved.
Keywords: Steady flow; Power-law fluids; Shear-thinning; Shear-thickening; Circular cylinder; Nusselt number; Constant wall temperature;
Uniform heat flux
1. Introduction
The steady cross-flow past a circular cylinder represents an idealization of many industrially important processes.
Typical examples include the flow on the shell side of tubular heat exchangers, pin fins, the use of thin wires as measuring sensors and probes, the use of screens to filter polymer melts and sewage sludges, etc. In addition
Ram Prakash Bharti a, R.P. Chhabra a,*, V. Eswaran b a b
Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, India
Department of Mechanical Engineering, Indian Institute of Technology, Kanpur 208016, India
Received 12 January 2006
Available online 12 October 2006
Abstract
Forced convection heat transfer to incompressible power-law fluids from a heated circular cylinder in the steady cross-flow regime has been investigated numerically by solving the momentum and thermal energy equations using a finite volume method and the QUICK scheme on a non-uniform Cartesian grid. The dependence of the average Nusselt number on the Reynolds number (5 6 Re 6 40), power-law index (0.6 6 n 6 2) and Prandtl number (1 6 Pr 6 1000) has been studied in detail. The numerical results are used to develop simple correlations as functions of the pertinent dimensionless variables. In addition to the average Nusselt number, the effects of Re, Pr and n on the local Nusselt number distribution have also been studied to provide further physical insights. The role of the two types of thermal boundary conditions, namely, constant temperature and uniform heat flux on the surface of the cylinder has also been presented.
Ó 2006 Elsevier Ltd. All rights reserved.
Keywords: Steady flow; Power-law fluids; Shear-thinning; Shear-thickening; Circular cylinder; Nusselt number; Constant wall temperature;
Uniform heat flux
1. Introduction
The steady cross-flow past a circular cylinder represents an idealization of many industrially important processes.
Typical examples include the flow on the shell side of tubular heat exchangers, pin fins, the use of thin wires as measuring sensors and probes, the use of screens to filter polymer melts and sewage sludges, etc. In addition
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