## THERMAL SCIENCE

International Scientific Journal

### EFFECT OF VARIABLE THERMAL CONDUCTIVITY ON THE MHD BOUNDARY-LAYER OF CASSON-NANOFLUID OVER A MOVING PLATE WITH VARIABLE THICKNESS

**ABSTRACT**

The effect of variable thermal conductivity on the characteristics of heat transfer and mechanical properties of a moving surface on a Casson nanofluid flow as a coolant has been studied in this paper. We used similarity transformation method to transform the equations of the governing boundary-layer into ODE which are solved numerically using a mix of fourth order Runge-Kutta method and find root technique. Different values relevant parameters have been studied on the features of velocity, temperature, and the profiles of concentration and discussed in details for different values of various parameter as shape parameter, heat source parameter, radiation parameter, and magnetic parameter. The results were compared with previous published researches and obtained it in a good agreement and the results were tabulated. Furthermore, Nusselt number, Sherwood number, and the skin friction values with different parameters were calculated and the influence of theses physical quantities on the mechanical properties on the surface are analyzed and discussed in details.

**KEYWORDS**

PAPER SUBMITTED: 2019-03-24

PAPER REVISED: 2019-05-20

PAPER ACCEPTED: 2019-06-05

PUBLISHED ONLINE: 2019-07-06

**THERMAL SCIENCE** YEAR

**2021**, VOLUME

**25**, ISSUE

**Issue 1**, PAGES [145 - 157]

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