Abstract
This investigation conducts a comparative study on the thermo-hydraulic performance of magnesium oxide nanoparticles dispersed in transformer oil (MgO/TrO) and a hybrid nanofluid containing both magnesium oxide and copper oxide nanoparticles (MgO-CuO/TrO). Key performance metrics including Overall Heat Transfer Coefficient (UHTC), Convective Heat Transfer Coefficient (CHTC), Nusselt number (Nu), friction factor (FF), and pumping power (PP) were evaluated across relevant ranges of temperature (30-70 ̊ C) and Reynolds number. Results indicate that the hybrid (MgO-CuO/TrO) nanofluid consistently demonstrates significantly enhanced heat transfer characteristics. Compared to the MgO/TO fluid, the hybrid formulation exhibited superior UHTC up to 55% enhancement, CHTC 14-24% enhancement, and Nusselt number 4-27% enhancement. The hybrid nanofluid showed higher friction factors in the range of 8-11% and consequently required 2.2-3.8% greater pumping power under similar operating conditions. While the incorporation of CuO nanoparticles improves the thermal performance of the MgO-based transformer oil with an increased oil pumping power effect.
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