Peristaltic Transport of Casson-Carreau Nanofluid in a Symmetric Channel: A Comparative Analysis

Abstract

This study investigates the peristaltic transport of a Casson-Carreau nanofluid through a symmetric channel under the effects of thermal radiation, chemical reaction, a porous medium, and activation energy. The Casson-Carreau model integrates yield-stress behaviour with shear-thinning rheology to improve the representation of non-Newtonian flow. The governing equations are formulated in the wave frame, non-dimensionalised, and solved numerically using the adaptive Runge-Kutta-Fehlberg (RKF) method. The parametric analysis indicates that increasing Brownian motion enhances the velocity, temperature, and concentration profiles, with the Carreau fluid exhibiting greater sensitivity than the Casson fluid. Thermophoresis increases the temperature while reducing nanoparticle concentration near the heated wall. Higher Grashof numbers and buoyancy ratios accelerate the flow, with the shear-thinning Carreau fluid showing a stronger response. Thermal radiation intensifies as the temperature ratio increases, whereas porosity suppresses fluid motion. Activation energy reduces concentration through inhibition of the chemical reaction, while higher Lewis numbers promote concentration accumulation. Overall, the Carreau fluid demonstrates enhanced flow characteristics because of its shear-thinning behaviour. These findings provide insights into peristaltic transport in biomedical devices, microfluidic systems, and thermal-management applications.