Wire Coating Analysis in MHD Flow and Heat Transfer of a Third Grade Fluid with Variable Viscosity in a Porous Medium with Internal Heat Generation/Absorption and Joule Heating

In this paper, the wire coating analysis in MHD flow and heat transfer of a third grade fluid with variable viscosity in a porous medium with internal heat generation/absorption and Joule heating has been investigated. In the present study wire coating is carried out using melt polymer satisfying third grade fluid model. In the present discussion (i) Reynolds Model (ii) Vogel’s Model are considered to account for temperature dependent viscosity. The boundary layer equations governing the flow and heat transfer phenomena are solved numerically by employing fourth order Runge-Kutta method and the effects of pertinent parameters such as permeability parameter, internal heat generation/absorption parameter and temperature dependent viscosity parameters on wire coating have been analyzed and are displayed with the help of graphs. It is important to remark that an increase in non-Newtonian parameter increases the velocity in the absence of porous matrix which agrees well with the results reported earlier but in the presence of porous matrix the velocity decreases in the entire span of the flow domain. One of the important aspects of the present study is that thermal boundary layer generates energy which causes an enhancement in temperature with an increase in heat generation parameter whereas for the case of heat absorption, the temperature falls. Further, the flow instability in the flows of extrusion die is well marked in case of Vogel’s model as pointed out by Nhan-Phan-Thien.