Numerical study on the influence of tri-nanoparticles suspension on heat transfer in MHD Oldroyd-B fluid

Abstract

This article studies the impact of multi-nanoparticles on the entropy generation where heat transfer in Oldroyd-B fluid is subjected to Joule heating and heat generation. ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$ is assumed to obey the constitutive behavior in the context of the Oldroyd-B model. Three types of nanoparticles (${{\text{Al}}}_{2}{{\text{O}}}_{3},{{\text{TiO}}}_{2}$ and ${{\text{SiO}}}_{2}$) are assumed to be dispersed simultaneously in ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$. The numerical scheme is used for the numerical simulations and simulations are observed and various predictions are made. The dynamics of entropy generation versus relaxation and retardation times. Momentum relaxation time is helpful in controlling entropy generation. It is also observed that ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$ with ${{\text{Al}}}_{2}{{\text{O}}}_{3}$ has minimum entropy generation relative to ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$ with ${{\text{Al}}}_{2}{{\text{O}}}_{3}$ and ${{\text{TiO}}}_{2}$ and ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$ with ${{\text{Al}}}_{2}{{\text{O}}}_{3},{{\text{TiO}}}_{2}$ and ${{\text{SiO}}}_{2}$. Relative to hybrid and mono-nanoparticles, the highest wall shear stresses are noticed in ${{\text{C}}}_{2}{{\text{H}}}_{6}{{\text{O}}}_{2}$ with tri-nanoparticles is observed. Momentum retardation time enhances entropy generation. Therefore, it is recommended not to use fluid with Oldroyd-B behavior in mechanisms where entropy generation is not required. In mechanisms where entropy generation is not required, the base fluid or nanofluid should not be heat-generating because heat generation helps in enhancing the generation of entropy. However, heat-absorbing fluid would be favorable for the minimization of entropy.