## THERMAL SCIENCE

International Scientific Journal

### BOUNDARY LAYER FLOW OF A COPPER-WATER NANOFLUID OVER A PERMEABLE SHRINKING CYLINDER WITH HOMOGENOUS-HETROGENOUS REACTIONS: DUAL SOLUTIONS

**ABSTRACT**

This research addresses the axi-symmetric flow of a Cu-water nanofluid past a porous shrinking cylinder in the presence of homogeneous-heterogeneous reactions. Using a similarity transformation, the basic PDE’s are converted into ODE’s. The transformed equations are solved using bvp4c numerically from MATLAB for several values of the physical parameters. The physical impact of governing parameters on the velocity profile, temperature profile, concentration profile as well as the skin friction coefficient, f”(0), and the heat transfer rate, -Θ’(0)are discussed carefully. The results indicate that the multiple solutions only exist when a certain value of suction is implemented through the permeable cylinder. Further, the curvature parameter, γ, accelerates the boundary-layer separation.

**KEYWORDS**

PAPER SUBMITTED: 2016-06-13

PAPER REVISED: 2017-04-04

PAPER ACCEPTED: 2017-04-28

PUBLISHED ONLINE: 2017-05-06

**THERMAL SCIENCE** YEAR

**2019**, VOLUME

**23**, ISSUE

**1**, PAGES [295 - 306]

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