Insight into the relationship between non-linear mixed convection and thermal radiation: The case of Newtonian fluid flow due to non-linear stretching

Amit Kumar Pandey ^a, Krishnendu Bhattacharyya ^a,*, Anil Kumar Gautam ^a, Sohita Rajput ^a, Mani Shankar Mandal ^b, Ali J. Chamkha ^c, Dhananjay Yadav ^d

a. Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India
         b. Department of Mathematics, Government General Degree College, Kalna–I, Burdwan-713405, West Bengal, India
         c. Faculty of Engineering, Kuwait College of Science and Technology, Doha District, Kuwait
         d. Department of Mathematical and Physical Sciences, University of Nizwa, Oman

Abstract: The current research focuses the light on the characterization of buoyancy-driven non-linear mixed convection and non-linear radiation in a Newtonian flow over a non-linearly stretching vertical sheet, and this type of flow has useful applications in many industrial processes, such as the paper and pulp industry, polymer industry, electronic device cooling, solar collectors, gas turbine plants, and nuclear power. Using appropriate transformations, governing PDEs for non-linear mixed convection are reduced to higher-order non-linear ODEs and those are numerically solved. Along with tabular presentations of computed results, the graphical representations are generated to elucidate the effects of involved parameters on convection transport properties and their inter-relations. It demonstrates that flow velocity increases near the surface and decreases away from the surface as the non-linear convection parameter increases. Furthermore, increments in the thermal buoyancy, temperature ratio and non-linear radiation parameters result in the boost of velocity. The temperature decreases as linear and non-linear buoyancy-related parameters (non-linear convection and thermal buoyancy parameters) are of higher levels. In contrast, the temperature rises with two non-linear thermal radiation-related parameters (thermal ratio and non-linear radiation parameters). For greater values of the non-linear stretching related parameter, a lower velocity and a higher temperature are witnessed. The non-linear convection, thermal buoyancy, thermal ratio and non-linear radiation parameters contribute toward the reduction of the magnitude of surface-drag force and growth of the surface cooling rate. But, with the non-linearity in surface stretching there are significant percentage hikes of surface-drag force magnitude and surface cooling rate.

Keywords: Non-linear mixed convection; Non-linear thermal radiation; Non-linear stretching sheet; Newtonian fluid

https://doi.org/10.1016/j.jppr.2022.11.002