Journal of Thermal Analysis and Calorimetry, cilt.149, sa.4, ss.1565-1579, 2024 (SCI-Expanded)
The combination of corrugated surfaces with nanofluid technology has attracted significant interest as a means to develop more efficient and reliable thermal applications. A computational study has been conducted using convergent–divergent (CD) nozzles with corrugated walls to study the forced convective laminar flow of blade-shaped mono nanofluids (TiO2/water, MgO/water, and CuO/water) and hybrid nanofluids (CuO–TiO2/water, CuO–MgO/water, and MgO–TiO2/water). All of the investigations, which are conducted for Reynolds numbers between 75 and 225, have used the smooth CD nozzle along with two corrugated CD nozzles, one with decreasing uniform wall corrugation (DUWC) and the other with increasing uniform wall corrugation (IUWC). The nanoparticle volume fraction for mono and hybrid nanofluids is 3.0%. The nanoparticle volume fractions of the nanoparticles forming the hybrid nanofluids are equal. Numerical simulation is achieved by discretizing the governing equations using finite volume techniques. Several heat transfer and flow parameters are discussed and analyzed numerically, including the performance evaluation criterion, friction factor, Nusselt number, temperature contours, and velocity streamlines. The findings show that CD nozzles with IUWC significantly improve heat transfer compared to DUWC and smooth nozzles. Between the minimum and maximum values of the Reynolds number, the Nusselt number increment rate for water in smooth, DUWC, and IUWC is 37.8, 83.32, and 105.57%, respectively. At a Reynolds number of 225 and with a smooth nozzle, adding CuO/water and MgO–TiO2/water increases the Nusselt number by 43.51 and 71.15%, respectively, compared to water. The MgO–TiO2/water hybrid nanofluid exhibits superior heat transfer characteristics over water and mono nanofluids in all nozzle geometries. The CD nozzle with IUWC provides the best conditions for heat transfer at a Reynolds number of 225 with the flow of the MgO–TiO2/water hybrid nanofluid.