Department of Physics, Radhakrishna Institute of Technology and Engineering, BijuPatnaik University of Technology, Odisha (India)
E-mail: mkn2122@gmail.com

Wire coating process is a continuous extrusion process for primary insulation of conducting wires with molten polymer for mechanical strength and protection in aggressive environments. In the present study wire coating is performed using melt polymer satisfying third grade fluid model. The novelty of this study is to analyze the effect of porosity, internal heat generation/absorption and varying temperature dependent viscosity on the wire coating. In the present discussion (i) Reynolds Model (ii) Vogel’s Model are considered to account for temperature dependent viscosity. The flow and heat transfer in a pressure type die have been investigated. The equations characterizing the flow and heat transfer phenomena are solved numerically by fourth order Runge-Kutta method and the effects of pertinent parameters are displayed with the help of graphs. It is interesting to remark that an increase in non-Newtonian parameter increases the velocity in the absence of porous matrix which coincides 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 decreases. 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.