Unsteady mixed convection flow in stagnation region adjacent to a vertical surface

Devi, CDS and Takhar , HS and Nath, G (1991) Unsteady mixed convection flow in stagnation region adjacent to a vertical surface. In: Warme und Stoffubertragung-Thermo & Fluid Dynamics, 26 (2). pp. 71-79.

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Abstract

The unsteady two-dimensional laminar mixed convection flow in the stagnation region of a vertical surface has been studied where the buoyancy forces are due to both the temperature and concentration gradients. The unsteadiness in the flow and temperature fields is caused by the time-dependent free stream velocity. Both arbitrary wall temperature and concentration, and arbitrary surface heat and mass flux variations have been considered. The Navier-Stokes equations, the energy equation and the concentration equation, which are coupled nonlinear partial differential equations with three independent variables, have been reduced to a set of nonlinear ordinary differential equations. The analysis has also been done using boundary layer approximations and the difference between the solutions has been discussed. The governing ordinary differential equations for buoyancy assisting and buoyancy opposing regions have been solved numerically using a shooting method. The skin friction, heat transfer and mass transfer coefficients increase with the buoyancy parameter. However, the skin friction coefficient increases with the parameter lambda, which represents the unsteadiness in the free stream velocity, but the heat and mass transfer coefficients decrease. In the case of buoyancy opposed flow, the solution does not exist beyond a certain critical value of the buoyancy parameter. Also, for a certain range of the buoyancy parameter dual solutions exist.

Item Type:	Journal Article
Publication:	Warme und Stoffubertragung-Thermo & Fluid Dynamics
Publisher:	Springer
Additional Information:	Copyright of this article belongs to Springer.
Department/Centre:	Division of Physical & Mathematical Sciences > Mathematics
Date Deposited:	07 Dec 2010 07:09
Last Modified:	07 Dec 2010 07:09
URI:	http://eprints.iisc.ac.in/id/eprint/34346

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