Entropy analysis of magneto-radiative SWCNT-MWCNT/H₂O hybrid nanofluid flow with slip boundary conditions

Abstract

In the presence of nonlinear thermal radiation, viscous dissipation, and heat source/sink, this paper investigates the impact of entropy generation and heat transfer on the flow of single-walled carbon nanotube (SWCNT)/water (H₂O) and SWCNT-multiwalled carbon nanotube (SWCNT-MWCNT)/water (H₂O) hybrid nanofluids under the influence of a permeable stretching sheet. We also take into account the velocity slip and thermal slip boundary conditions. By using the correct similarity transformations, the nonlinear partial differential equations are transformed into ordinary differential equations. The Runge–Kutta-Fehlberg method (RKF45) with the shot approach is then used to numerically solve the generated dimensionless model. It is also noticed that the frictional coefficient, local Nusselt number, temperature distribution, and fluid velocity are all significantly affected by the presence of SWCNT-MWCNT based hybrid nanofluid. Using the second law of thermodynamics, we can determine the total entropy production using Bejan number, which is very sensitive to the values of the nanoparticle volume fraction, magnetic parameter, and radiation parameter. The results show that the skin friction coefficient decreases with increasing nanoparticle volume fraction and magnetic field, whereas the local Nusselt number increases due to heat radiation and increasing nanoparticle volume fraction. Furthermore, it is shown that the rate of heating/cooling of hybrid nanofluid is greater than that of mono nanofluid. Researchers have not made any efforts to optimise entropy using a SWCNT-MWCNT/H₂O hybrid nanofluidmodel, taking into account the impacts of nonlinear thermal radiation and an external magnetic field, as well as the effects of velocity and thermal slip. After comparing the cooling and heating capabilities of mono and hybrid nanofluids, we can say that hybrid nanofluids are superior, and that their usage in the construction of efficient electromagnetic appliances is of the utmost importance.

KEYWORDS:

• Hybrid nanofluid
• magnetic field
• non-linear thermal radiation
• heat source/sink
• generation of entropy
• permeable stretching surface

Disclosure statement

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

Data availability

The data that supports the findings of this study are available within the article.