Impact of needle size and distinct flow conditions on thermal performance of TiO₂–MWCNTs hybrid nanofluid flow past thin needle using Casson fluid model

Abstract

Hybrid nanofluids comprising carbon nanotubes (CNTs) are finding applications in advanced heat exchange technologies due to the unusually high thermal conductivity and chemically inert nature of CNTs. The thermal performance of a hybrid nanofluid, comprising MWCNTs and TiO 2 nanoparticles and flowing past a thin hot needle, is investigated in the present article. The Sakiadis and Blasius hybrid nanofluid flow scenarios around a parabolically shaped thin hot needle are modeled by using a non-Newtonian Casson fluid model coupled with the energy equation. The governing equations are coupled non-linear partial differential equations which are solved by the shooting method along with the 4th order Runge-Kutta method. The main aim of the study is to perform a comparative analysis among the base fluid (which is a 50:50 mixture of ethylene glycol [EG] and water), TiO 2 /EG-water nanofluid, and TiO 2 -MWCNTs/EGwater hybrid nanofluid and to analyze which fluid is the best transporter of heat. Apart from this, the impact of needle size and different flow conditions on heat transport is investigated. The numerical results reveal that the rate of heat transfer is maximum for TiO 2 -MWCNTs/EG-water hybrid nanofluid among the base fluid, nanofluid, and hybrid nanofluid. The magnitude of the Nusselt number is high for the case of the Blasius flow than for the Sakiadis flow.

Mixed Convection Flow of a Casson Fluid Past a Thin Needle

“…Rehman et al, [28] investigated the Soret and Dufour impact on electroosmotic forces in the flow of Casson fluid towards a stretchable sheet with bioconvection, Viscous and Joule dissipation effects. Using a non-Newtonian Casson fluid model, Prashar [29] examined the Blasius and Sakiadis hybrid nanofluid stream all over narrow, heated needle.…”