## THERMAL SCIENCE

International Scientific Journal

### DOUBLY STRATIFIED EFFECTS IN A FREE CONVECTIVE FLOW OVER A VERTICAL PLATE WITH HEAT AND MASS TRANSFER

**ABSTRACT**

An analysis is performed to study the effects of thermal and mass stratification in a transient free convective flow of a viscous, incompressible fluid past an isothermal vertical plate. The governing boundary layer equations are solved numerically using an implicit finite difference scheme of Crank-Nicolson type. The doubly stratified effects on the velocity, temperature and concentration are shown graphically. It is observed that an increase in thermal stratification parameter decreases the velocity, temperature profiles and increases the concentration profiles. As well, increase in mass stratification parameter decreases the velocity, concentration profiles and increases the temperature profiles. Also, the influence of the thermal and mass stratification parameter on local as well as average skin-friction, the rate of heat and mass transfer are discussed and presented graphically. The results are compared with particular solutions available in the literature. The present results are found to be in good agreement with the existing particular solution of the problem.

**KEYWORDS**

PAPER SUBMITTED: 2011-10-06

PAPER REVISED: 2012-08-15

PAPER ACCEPTED: 2012-10-26

**THERMAL SCIENCE** YEAR

**2014**, VOLUME

**18**, ISSUE

**Issue 2**, PAGES [365 - 376]

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