Slip-driven thermal transport in axisymmetric pipe flow of Sisko fluid with internal heat generation

This study presents an analytical investigation of steady laminar flow and heat transfer of a non-Newtonian Sisko fluid in a circular pipe, motivated by its important applications in polymer processing, biomedical systems, and thermal engineering. The model incorporates velocity and thermal slip, along with internal heat generation/absorption and viscous dissipation, to represent realistic physical conditions. The governing nonlinear equations are solved using the regular perturbation method, yielding closed-form expressions for velocity and temperature distributions up to first order. The influence of key parameters, including the non-Newtonian parameter, slip coefficients, Brinkman number, and heat generation parameter, is examined. The results show that increasing the non-Newtonian parameter enhances axial velocity and heat transfer. Moreover, higher Brinkman number and heat generation significantly elevate the temperature due to combined viscous and internal heating effects. The obtained results are in good agreement with existing studies, confirming the validity of the analytical approach. These findings provide useful physical insight for the design and optimization of systems involving non-Newtonian fluid flow and heat transfer.