Similarity Solution of Unsteady Convective Heat and Mass Transfer Flow along an Isothermal Vertical Plate with Suction

Abstract

In this study the similarity solutions of unsteady convective boundary layer heat and mass transfer flow of viscous incompressible fluid along an isothermal plate with suction is investigated. The similarity equations of the specified problem are obtained first by employing the usual similarity technique and Bousinesq approximation. Then the set of transformed ordinary differential equations has been solved numerically adopting the 6th order Range-Kutta method and to enumerate the unspecified initial conditions shooting method has been adopted. The non-dimensional solutions regarding the velocity, temperature and mass concentration have been found for different selected values of the established dimensionless numbers and parameters entering into the problem. The effect of suction on fluid flow and temperature fields as well as concentration distributions and other topics of interest like skin friction and heat transfer coefficients are extensively investigated. It is observed that the velocity at any point within the boundary layer increases with the increase of suction parameter (Fw). But both temperature and mass concentration decrease rapidly with the increasing values of Fw. The effects of some other involved dimensionless numbers and parameters like Prandtl number (Pr), local concentration Grashof number (Gc) and unsteadiness parameters (A1, A2, A3) on the velocity and temperature fields and on the concentration distributions have been investigated. The results show that fluid velocity decreases slowly but temperature decreases significantly with the increase of Pr whereas no appreciable change is found on concentration for increasing values of Pr. It is also found that velocity increases highly with the increase of Gc while the impact of Gc on the temperature and concentration are very diminutive. All the unsteadiness parameters also apparently affect the velocity, temperature and concentration distributions. The obtained numerical results involving the effects of these non-dimensional numbers and parameters on the velocity, temperature and concentration profiles are displayed with the help of various graphs. Finally, the dependency of wall shear stress (in terms of local Skin-friction coefficients) and wall heat flux (in terms of Nusselt number), which are of physical interests, on the concerned non-dimensional parameters and numbers are also illustrated and discussed through the tables. The obtained results might be of great interest for the creative learners regarding aerodynamics and hydrodynamics including industrial applications.