Considering the thermal conductivity variation is crucial in modifying transport characteristics when the temperature difference in the boundary layer is notable. These include drag reduction in coating manufacturing, petroleum purification and heavy oil transport systems. Motivated by these applications, this study aims to examine the characteristics of nanofluid flow past a horizontal cylindrical surface with heat source/sink and thermal radiation. The nanofluid is prepared by suspending the Single-Walled Carbon Nanotubes (SWCNTs)/Multi-Walled Carbon Nanotubes (MWCNTs) in water (H2O)/ethylene glycol (C2H6O2). The energy equation is constituted with the influence of viscous dissipation and joule heating.
Appropriate transformation quantities are considered to obtain a set of ordinary differential equations from the governing boundary layer partial differential equations. The implicit Keller box method is adopted to obtain the numerical solution of this study. The accuracy of the KBM simulations is examined by comparing the results with those of earlier studies and obtained good agreement.
The characteristics of flow, heat transfer, friction factor and Nusselt number for the variation of pertinent parameters, such as nanoparticle volume fraction, Eckert number, Weissenberg viscoelastic parameter and magnetic field parameter, are visualized graphically. It is noticed that magnifying the strength of the magnetic field diminishes skin friction. Skin friction coefficient is somewhat more dominant for SWCNT-H2O/C2H6O2 nanofluid compared to MWCNT-H2O/C2H6O2 nanofluid. Further, it is noticed that the skin friction coefficient is slightly more significant for MWCNT/SWCNT-H2O nanofluid compared to MWCNT/SWCNT-C2H6O2 nanofluid. For both carbon nanotubes, higher values of magnetic field and Eckert number decrease the Nusselt number.
Thermal conductivity is considered to vary linearly with a fluid temperature of SWCNT/ MWCNT-H2O/C2H6O2 nanofluid. The role of thermal conductivity is prime in many applications like coating manufacturing, petrochemical and petroleum refinement.
Analyzing the heat transfer characteristics of SWCNT/ MWCNT-H2O/C2H6O2 nanofluid flow may be useful in examining the features of thermal management capabilities of working fluids for various applications, including heat exchangers, vehicle thermal management, hybrid-powered engines, industrial cooling, microelectronics cooling and solar-powered systems.
The characteristics of the magnetohydrodynamic MWCNT/SWCNT-water/ethylene glycol-based nanofluid flow over the horizontal cylindrical surface are analyzed using the Keller-box method. The impact of fluid thermal conductivity variation, non-uniform heat source/sink, viscous dissipation and Ohmic heating is taken into consideration to predict the energy transmission characteristics more precisely. The outcomes elucidate that for all the considered effects, fluid temperature is slightly higher for MWCNT/SWCNT-ethylene glycol nanofluids than MWCNT/SWCNT-water nanofluids. On the other hand, for all the considered effects, the fluid velocity is slightly higher for MWCNT/SWCNT-water nanofluids compared with MWCNT/SWCNT-ethylene glycol nanofluids.
