A multi-domain spectral method for non-Darcian mixed convection flow in a power-law fluid with viscous dissipation

ABSTRACT

The purpose of this study is to investigate non-Darcian mixed convection flow, heat and mass transfer in a non-Newtonian power-law fluid over a flat plate embedded in porous medium with suction and viscous dissipation and also is to demonstrate the application and utility of a recently developed multi-domain bivariate spectral quasi-linearisation method (MD-BSQLM) in finding the solutions of highly nonlinear differential equations. The flow is subject to, among other source terms, internal heat generation, thermal radiation and partial velocity slip. The coupled system of nonlinear partial differential equations are solved using a MD-BSQLM to find the fluid properties, the skin friction, as well as the heat and mass coefficients. We have presented selected results that give the significance of some system parameters on the fluid properties. This MD-BSQLM has not been used before in the literature to find the nature of the solutions of power-law fluids. Indeed, validation of this numerical method for general fluid flows, heat and mass transfer problems has not yet been done. This study presents the first opportunity to evaluate the accuracy and robustness of the MD-BSQLM in finding solutions of non-Newtonian fluids.

KEYWORDS:

• Power-law fluid
• partial slip
• non-similarity solution
• multi-domain bivariate spectral quasi-linearisation method

Acknowledgement

The authors wish to thank the University of KwaZulu-Natal and DST-NRF Centre of Excellence in Mathematical and Statistical Sciences (CoE-MaSS) for necessary support.

Disclosure statement

No potential conflict of interest was reported by the authors.The authors declare that there is no conflict of interests regarding the publication of this article.