Thermo-magnetic convection of MHD Casson fluid in a wavy triangular porous cavity with embedded a cold inverted triangle obstacle

Abstract

The design of enclosures is crucial in thermal engineering applications and technologies, encompassing areas such as electronics, heat transfer devices, power reactors, heating systems, solar panels, and nuclear power plants. Thermal efficiency in microchannels is optimized and improved by using triangular enclosures with varying aspect ratios. Specifically, the purpose of these triangular enclosures with cool cylinders is to reduce energy loss in nanoscale thermal sinks and thermal exchange devices. The current study aims to explore the thermal radiation effects on magnetohydrodynamic $\mathit{\text{MHD}}$ Casson fluid flow within a wavy triangular cavity that includes an embedded cold inverted triangle. The inner inverted triangle is kept at a lower temperature, while the wavy bottom wall of the outer triangular cavity acts as an isothermal heat source at a higher temperature. The numerical solution for this mathematical model is obtained using the open-source finite element software COMSOL. In this study, the wavy triangular enclosure is analyzed for key parameters such as Casson parameter $\beta ,$ Hartmann number $\mathit{\text{Ha}},$ Rayleigh number $\mathit{\text{Ra}},$ numbers of undulation $N,$ radiation $\mathit{\text{Rd}}$ and inclination $\gamma .$ The study presents the local distribution of streamlines, velocity profiles, isothermals, and entropy production, along with the ${\mathit{\text{Nu}}}_{\mathit{\text{avg}}}.$ The results reveal the rate of heat transport and total entropy production raise with the increasing number of undulations $N$ and the Casson parameter $\beta ,$ while they decrease with increasing Hartmann number $\mathit{\text{Ha}}.$ The number ${\mathit{\text{Nu}}}_{\mathit{\text{avg}}}$ rises with the increasing radiation parameter $\mathit{\text{Rd}}$ and Rayleigh number $\mathit{\text{Ra}}.$ The maximum stream function is observed at an inclination angle of $60°.$

Keywords:

• Embedded cylinders
• FEM
• MHD
• natural convection

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data will be made available on request.

Additional information

Funding

This work was funded by the National Natural Science Foundation of China (NSFC-12032011, 11772154).