%0 Journal Article
%T Chemical Reaction Effect on Transient Free Convective Flow past an Infinite Moving Vertical Cylinder
%A Ashish Paul
%A Rudra Kanta Deka
%J International Journal of Chemical Engineering
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/531513
%X An analysis is performed to study the heat and mass transfer on the flow past an infinite moving vertical cylinder, in the presence of first-order chemical reaction. The closed-form solutions of the dimensionless governing partial differential equations are obtained in terms of Bessel's functions and modified Bessel's functions by the Laplace transform technique. The transient velocity profiles, temperature profiles, and concentration profiles are studied for various sets of physical parameters, namely, the chemical reaction parameter, Prandtl number, Schmidt number, thermal Grashof number, mass Grashof number, and time. The skin friction, Nusselt number, and Sherwood number are also obtained and presented in graphs. It is observed that in presence of as well as increase in chemical reaction the flow velocity decreases. Also, in presence of destructive chemical reaction the concentration profile and Sherwood number tend to the steady state at large time. 1. Introduction Combined heat and mass transfer in natural convection flows along moving vertical cylinders has got considerable attention in the last few decades because of its wide engineering and industrial application such as in hot rolling, hot extrusion, nuclear reactor cooling system, and underground energy system. Sparrow and Gregg [1] first studied the heat transfer from vertical cylinders. Goldstein and Briggs [2] presented an analysis of the transient free convective flow past vertical flat plate and circular cylinder for the unit and variable Prandtl number by employing the Laplace transform technique. Ishak [3] studied mixed convection over a vertical cylinder in presence of heat flux, while Lien et al. [4] studied the effects of free convection and mass transfer on the flow past an impulsively moving infinite vertical circular cylinder. But, in nature, the presence of pure air or water is rather impossible. It is always possible that either foreign mass is present naturally in air or water, or foreign masses are mixed with air or water. A simple example is the naturally available water vapor that causes the flow of air. In many chemical engineering processes, there is chemical reaction between a foreign mass and the fluid in which the cylinder is moving. The rate of reaction, which is directly proportional to the concentration, is termed as first order chemical reaction. The effect of a chemical reaction depends on whether the reaction is homogeneous or heterogeneous. Chambr¨¦ and Young [5] have analyzed a first order chemical reaction in the neighborhood of a horizontal plate. Das et al.
%U http://www.hindawi.com/journals/ijce/2013/531513/