The Effect of Copper Nanofluid Flow over the Rotating Drum of an Electric Generator

Abstract

Nanofluid is a mixture of solid nanoparticles and water with a high or low volume fraction suspended within the base fluid. This research aims to investigate the effects of copper nanofluid flow over the rotating drum of an electric generator. Adding copper nanofluids to an electric generator is vital as it improves electrical conductivity; thus, they both become more efficient. It is essential to determine the fluid flow performance when there are no copper particles and when the nanofluid particles are present. Investigating the effects of copper nanofluid on rotating machinery provides the opportunity to study its fluid flow properties, a knowledge gap that has not, to date, been studied. This study also considers the instability effect of the boundary layer and when suction is added to the fluid flow. This research starts by analysing the influence of steady water flow over the rotating disks, where no nanofluids have been added. The Navier-Stokes equation, a partial dif ferentiation equation, is used to describe the fluid flow on a rotating drum. Furthermore, this research extends its analysis using the MM and MT models, where the magnetic field induction is analysed, and various nanofluids are compared, here Ag, Cu, CuO, Al2O3, and TiO2, because they have differing fluid properties. The MM model applies the Buon giorno model (a mathematical model that describes the behaviour of nanofluids through the use of Brownian motion) to combine Brownian motion and the nanofluid’s electrical particles to solve the Von K´arm´an equation. On the other hand, the MT model con centrates on the influence that various nanoparticle fractions have on the mean velocity of a revolving drum. After the water is added over the rotating disks and its effects are analysed, copper, Cu, nanoparticles are added to water where stable and unstable areas are identified using steady flow and neutral curves. The effects of suction on the stability features of the boundary layer flow are analysed, and a comparison is made between the instability flow and the mass flux of instability of the nanofluids. This research uses water as the base fluid, which is the primary fluid used to study the properties of various nanoparticles. The findings in this research conclude that using water as the base fluid reduces the steady velocity of the fluid flow on the rotating drum, with the axial velocity (W) being the most affected, and the radial velocity (U) being the least, compared to the absence of fluid. The MM model uses the Buongiorno model to conclude that increasing the magnetic field reduces the radial velocity of the rotating model. The MT model describes Cu as having the greatest electrical properties compared to other nanoparticles. In addition, investigating the instability flow concludes that increasing ϕ (the nanovolume fraction) from 0 to 0.3 pushes the commencement of the convective instability to higher values of the critical Reynolds number. As the Rossby number increases from -1 to 1, the critical Reynolds number also increases, causing the steady flow of Cu to become unstable as its width increases. Suction is a stabilising mechanism on the identified unstable zones in the fluid flow. It stabilises unstable areas by restricting the growth rates of all the various forms of instability. Therefore, the results of this study conclude that suction is an effective method to use in electrical conductivity compared to the stability flow, where nanofluid flow is being considered.