Thermophysical characteristics with natural convective flow of Carreau fluid influencing by Soret and Dufour effects: By using numerical technique

Abstract

The authors are attracted to conduct this study because it has a major dependence on scientific, medical, and engineering works, including heat exchangers, geothermal systems, reactive flow in chemical reactors, blood flow in arteries, groundwater flow, enhanced oil recovery, cooling systems in aircraft, and nanofluidic devices. In this study, the problem deals with the two-dimensional incompressible and boundary layer natural convective flow of Carreau fluid flowing on a surface with variable thickness. The thermophysical properties like viscosity, thermal conductivity, and thermal diffusivity are chosen to be variable. For the determination of solutal and thermal analysis, we have considered the enthalpy change along with activation energy, heat generation, Soret, and Dufour effects. The model equations occur in PDEs form and then converted into ODEs via similarity transformations. The numerical outcomes of ODEs are obtained by using a multistep method named the Adams-Bashforth method with the Predictor and Corrector technique in MATLAB software. The velocity of fluid is a decreasing function of the Weissenberg number, the viscosity coefficient, and both the Grashof numbers of thermal and solutal transport. The temperature field is a growing function of the Damkholer number, thermal conduction coefficient, and heat generation parameter, whereas declining behavior is noted due to the Dufour number and thermal difference coefficient. The concentration field rises with the increasing inputs of the activation coefficient and Damkholer number, but a decline in concentration is noted due to the Soret number. The numerical determination of skin friction, the Nusselt number, and the Sherwood number are also discussed here, and these numerical outcomes are compared with Bvp4c and Bvp5c built-in commands on Matlab software.

Keywords

• Carreau fluid
• Variable thickness surface
• Activation energy
• Convection
• Enthalpy
• Soret and Dufour effect