Alexandria Engineering Journal (May 2023)
Various nanoparticle shapes and quadratic velocity impacts on entropy generation and MHD flow over a stretching sheet with joule heating
Abstract
The purpose of this research was to examine the impact of NP shape on the entropy production of a water-alumina nanofluid over a permeable MHD stretching sheet at quadratic velocities with viscous dissipation and joule heating. The hot fluid is water-alumina nanofluid, which consists of four different NP shapes (brick, platelet, blade, and oblate spheroid), and the cool fluid is water itself. As a result of its exceptional ability to enhance heat transmission, Al2O3-H2O nanofluid is used extensively in industrial production. The governing PDEs are changed into a nonlinear differential system of coupled ODEs by a series of similarity transformations. The code, in MATLAB, is an effective version of the Runge-Kutta technique for obtaining numerical solutions. In the region behind a stretching sheet, the wall shear stress increases by almost 6.3% for increases in the volume fraction of nanoparticles from 0% to 2% and by 12.6% for increases from 0% to 4%. When the magnetic effect accounts for roughly 5 percent of the boundary layer flow, there is an approximately 16.4 percent increase in the rate of convective heat transfer. The frictional force and thermal entropy produced by nanofluids with blade-, brick-, and Os-shaped NPs was lower than that produced by nanofluids with platelet-shaped NPs. On the cold fluid side, the nanofluid with Os-shaped NPs develops thermal entropy at a faster rate than those with brick-, blade-, cylinder-, and platelet-shaped NPs.