## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Unsteady homogeneous-heterogeneous reactions in MHD nanofluid mixed convection flow past a stagnation point of an impulsively rotating sphere

**ABSTRACT**

This paper establishes a mathematical analysis for describing the homogeneous and heterogeneous chemical reactions in the nearness of stagnation region of a sphere immersed in a single-phase nanofluid due to a Newtonian heating. The flow is resulted by an impulsively rotating sphere, and the nanofluid involves nanoparticles of Copper and Ferro. The available unsteady-states of the considered system are given in the case when the diffusion coefficients of both reactant and auto catalyst have the same size. The resulting non-linear dimensionless coupled partial differential equations in which governing the mixed convection flow have been tackled numerically via an implicit finite difference technique in combination with the quasi-linearization scheme. The similarities and differences in the behavior of physical pertinent fluid parameters have been elaborated and discussed graphically. It has been clarified that the nanofluid velocity and temperature profiles grow gradually by adding nanoparticles in the base fluid. Again it is noticed from present contribution that concentration of the nanofluid is decreases function by rising the strength of homogeneous and heterogeneous chemical reactions. Finally, numerical computations of the skin friction and heat transfer factors are presented.

**KEYWORDS**

PAPER SUBMITTED: 2019-07-12

PAPER REVISED: 2019-07-30

PAPER ACCEPTED: 2019-08-07

PUBLISHED ONLINE: 2019-10-06

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