Prediction of hybrid nanofluids behavior and entropy generation during the cooling of an electronic chip using the Lagrangian–Eulerian approach

Abstract

AbstractA numerical study is performed to predict the behavior of hybrid nanofluids and entropy generation in a cooling application problem using the Lagrangian–Eulerian approach. The equations governing the continuous phase (base fluid) were solved using the finite volume technique, while the discrete phase (nanoparticles) was tracked using the force balance equation of particles. The interaction between the base fluid and the nanoparticles was considered. Brownian motion and the thermophoresis effect have been included in the solver specifications. In the first step, the numerical procedure using the discrete phase model (DPM) has been thoroughly validated with previous published numerical data, and a good agreement has been achieved. After that, various parameters are adopted by varying nanoparticles' diameter (dp), volume fraction (ϕ), and Reynolds number (Re). Their imprints have been highlighted on isotherms, streamlines, Nusselt numbers, entropy generations (Sg), and Bejan numbers (Be). It is found that the entropy generation is more pronounced at the electronic chip corners. Heat transfer is enhanced, and entropy generation increases when the solid volume fraction and Reynolds number grow. However, the Nusselt number and irreversibility decrease when increasing the nanoparticle diameter. In addition, the results substantiate that the thermal entropy generation prevails over the friction entropy generation, resulting in high values of the Bejan number. Finally, variations in the distribution of isotherms, streamlines, and local entropy generation are noted between the DPM and single‐phase model (SPM) approaches. Also, the average Nusselt number is higher in SPM than in the DPM approach, but the opposite is observed for the entropy generation and the Bejan number.