## THERMAL SCIENCE

International Scientific Journal

### COMBINED EFFECTS OF VARIABLE VISCOSITY AND THERMOPHORETIC TRANSPORTATION ON MIXED CONVECTION FLOW AROUND THE SURFACE OF A SPHERE

**ABSTRACT**

The physical behavior of the combined effect of temperature dependent viscosity and thermophoretic motion on mixed convection flow around the surface of a sphere is investigated. The set of non-linear coupled PDE is formulated and then non-dimensionalized by using an appropriate set of dimensionless variables. The dimensionless model is then transformed to convenient form for integration by employing a suitable set of primitive variables formulation and then discretized by using an efficient implicate finite difference scheme for numerical simulation. The effect of controlling parameters on velocity profile, temperature profile, and mass concentration as well as skin friction, rate of heat transfer, and mass transfer rate are analyzed. The obtained numerical results for different values of controlling parameters indicate that, velocity profile gains its largest magnitude at position X = 1.5 radian and slows down at postion X = π radian. It is also predicted that the temperature distribution and mass concentration are diluted at position X = 1.5 radian due to rapid motion of fluid. The numerical results are highlighted in graphical as well as in tabular form.

**KEYWORDS**

PAPER SUBMITTED: 2019-05-18

PAPER REVISED: 2020-03-16

PAPER ACCEPTED: 2020-03-19

PUBLISHED ONLINE: 2020-04-04

**THERMAL SCIENCE** YEAR

**2020**, VOLUME

**24**, ISSUE

**6**, PAGES [4089 - 4101]

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