INVESTIGATION OF HEAT TRANSFER IMPROVEMENTS OF GRAPHENE OXIDE-WATER AND DIAMOND-WATER NANOFLUIDS IN CROSS-FLOW-IMPINGING JET FLOW CHANNELS HAVING FIN

Abstract

In this study, the heat transfer from two different model surfaces (roof and crown) and flow structure in the channels with the cross flow-impinging jet flow were numerically analyzed by using water, 0.02% GO (Graphene Oxide)-Water and 2% Diamond-Water nanofluids. The numerical study was carried out steady and three dimensional using the Ansys-Fluent program with k-ε turbulence model. A fin with 90o angle was added on the upper channel surface from the impinging jet inlet at distinct distances. A constant heat flux of 1000 W/m2 was applied to the model surfaces. The channel heights are fixed and the Re range of the fluids is 5000-15000. The numerical results obtained from the study were compared with the results of the experimental studies in the literature and it was seen that the results were compatible and acceptable. The results of the study were comparatively examined for water and nanofluids as the mean Nu and surface temperature variations for each model in the channels without fins and at different fin distances. Also, velocity and temperature contour distributions of the combined jet Diamond-Water nanofluid flow were visualized. However, performance coefficient (C) and mean Nu (Num) and, surface temperature values (Tm) were evaluated for all three patterned surfaces in the channels. Num increases for GO-Water nanofluid at Re=15000 and fin distance of 2D are 47.53% and 57.42% compared to the case of using finless and water fluid for the roof and crown model surfaces, respectively.