## THERMAL SCIENCE

International Scientific Journal

### MIXED CONVECTION BOUNDARY-LAYER FLOW OF A VISCOELASTIC FLUID DUE TO HORIZONTAL ELLIPTIC CYLINDER WITH CONSTANT HEAT FLUX

**ABSTRACT**

This article presents numerical analysis of mixed convection laminar flow of a second grade viscoelastic fluid due to cylinder of elliptic cross-section with prescribed surface heat flux. Dimensionless non-linear analysis is computed employing Keller-box method. Skin friction coefficient and Nusselt number are emphasized specifically. These quantities are displayed graphically to examine their behavior along the surface of cylinder. The flow and heat transfer rates are carefully judged while varying the important resulting parameters (mixed convection parameter, viscoelastic parameter aspect ratio, etc.) through sketched graphs keeping major axis of ellipse along and perpendicular to the horizontal. These two positions of major axis are termed as blunt and slender orientations, respectively. The values of skin friction and Nusselt number increase with rise in mixed convection parameter. On the other hand, these quantities lessen by increasing the value of viscoelastic parameter.

**KEYWORDS**

PAPER SUBMITTED: 2015-01-20

PAPER REVISED: 2016-12-08

PAPER ACCEPTED: 2016-12-11

PUBLISHED ONLINE: 2017-01-14

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**1**, PAGES [519 - 531]

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