Analysis of thermophoretic and brownian motion effects on Newtonian and Non-Newtonian fluid flow through a porous stretching surface

Abstract

The present work explores the intricate thermo-fluid dynamics of Newtonian and non-Newtonian nanofluids flowing over a porous, deformable stretching surface. The analysis incorporates the combined influences of thermal radiation, thermophoretic force, Brownian motion, and dual-phase-lag models of heat and mass diffusion. Darcy–Forchheimer drag and slip boundary effects are also considered to represent realistic flow resistance within porous media. Through similarity transformations, the governing nonlinear partial differential equations are reduced to ordinary differential form and numerically solved using MATLAB’s bvp4c algorithm. The study reveals that enhanced permeability and slip parameters attenuate fluid motion, whereas intensified Brownian motion and porous resistance elevate the thermal boundary layer. The findings confirm that nanofluids offer superior heat transport capabilities, making them promising candidates for applications in thermal regulation and biomedical heat exchange systems. Model validation against previously published results demonstrates strong agreement, reinforcing the reliability of the numerical approach.