## THERMAL SCIENCE

International Scientific Journal

### HALL CURRENT AND JOULE HEATING EFFECTS ON FREE CONVECTION FLOW OF A NANOFLUID OVER A VERTICAL CONE IN PRESENCE OF THERMAL RADIATION

**ABSTRACT**

The effects of Hall current and Joule heating on flow and heat transfer of a nanofluid along a vertical cone in the presence of thermal radiation is considered. The flow is subjected to a uniform strong transverse magnetic field normal to the cone surface. Similarity transformations are used to convert the non-linear boundary- layer equations for momentum and energy equations to a system of non-linear ordinary differential equations which are then solved numerically with appropriate boundary conditions. The solutions are presented in terms of local skin friction, local Nusselt number, velocity, and temperature profiles for values of magnetic parameter, Hall parameter, Eckert number, radiation parameter, and nanoparticle volume fraction. Comparison of the numerical results made with previously published results under the special cases, the results are found to be in an excellent agreement. It is also found that, nanoparticle volume fraction parameter and types of nanofluid play an important role to significantly determine the flow behavior.

**KEYWORDS**

PAPER SUBMITTED: 2016-04-13

PAPER REVISED: 2017-03-21

PAPER ACCEPTED: 2017-03-27

PUBLISHED ONLINE: 2017-04-08

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**6**, PAGES [2609 - 2620]

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