Abstract
This study focused on the numerical investigation of heat transfer from various shaped copper plate surfaces exposed to a constant heat flux of 1000 W/m2. The analysis employed a combination of cross-flow and impinging jet flows. The numerical simulations were carried out by solving the energy and Navier–Stokes equations using the Ansys–Fluent computer program with the \(k\) - \(\varepsilon\) turbulence model. To guide the combined jet flow towards the heated surfaces in the channel, horizontal fins with 30° and 60° angles were placed in the channel. The channel height ( \(H\) ) was set at 4 times the diameter ( \(D\) ), and the fin distance from the jet inlet ( \(N\) ) was equal to \(D\) . Different fin lengths of \(D\) , \(1.166D\) , and \(1.333D\) (K) were utilized in the channels. The study considered three types of fluids: water, 2% CuO-Water, and 0.02% GO-Water nanofluids. The upper and lower surfaces of the channel and the fin were assumed to be adiabatic, and the Reynolds number of the flow ranged from 5000 to 15000. The results of this work were compared with experimental studies from the literature, and good agreement was found between them. Unlike previous studies, this research explored the effects of fin lengths and fin angles on heat transfer from differently shaped surfaces and the flow structures created by the fins in the channels, using GO-Water and CuO-Water nanofluids. The results were presented in terms of the mean Nusselt number variations for each model surface. Additionally, velocity and temperature contour distributions of the combined jet flow along the channel for CuO-Water nanofluid were analyzed. Performance Evaluation Coefficient (PEC) values, along with average Nusselt number (Nu \(_{m})\) and surface temperature ( \(T_{m})\) values, were assessed at different Reynolds numbers for all three patterned surfaces in the channels. At Re = 5000 and \(K=D\) , there were significant increases in Nu \(_{m}\) values for cube, roofed, and square hollow model surfaces when using a 60° fin and GO-Water nanofluid compared to channels with water flow and no fins.
