## THERMAL SCIENCE

International Scientific Journal

### EFFECT OF THERMAL RADIATION ON UNSTEADY MIXED CONVECTION FLOW NEAR FORWARD STAGNATION POINT OVER A CYLINDER OF ELLIPTIC CROSS SECTION

**ABSTRACT**

The effect of thermal radiation on unsteady mixed convection flow near a forward stagnation point over a cylinder of elliptic cross section is investigated in this paper. The governing equations are transformed into dimensionless partial differential equations by using a suitable transformation and then are solved numerically by using an implicit finite difference scheme known as Keller Box method. The accuracy of the results is verified by comparing the obtained results with the previous studies available in the literature. It is shown that the results are highly accurate and are in good agreement. The separation times for both blunt and slender orientations in the presence of thermal radiation are shown in tabular forms. Moreover, the effects of pertinent parameters including Prandtl number Pr, mixed convection parameter λ, thermal radiation parameter Rd, surface temperature parameter qw and blunt/slender orientation parameter w on the velocity profile, the temperature profile and the Nusselt number are shown graphically. From the present study, it is observed that boundary layer separation occurs early due to thermal radiation and Nusselt number increases for both blunt and slender orientations.

**KEYWORDS**

PAPER SUBMITTED: 2014-09-26

PAPER REVISED: 2014-02-02

PAPER ACCEPTED: 2015-02-16

PUBLISHED ONLINE: 2015-03-08

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**1**, PAGES [243 - 254]

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