Enhancing cooling efficiency: Innovative geometric designs and mono-hybrid nanofluid applications in heat sinks

This research investigates block-type heat sinks in different configurations, departing from the conventional circular cross-section pin-type heat sinks commonly found in literature. The study numerically examined eight different geometries, including vertical and horizontal flow directions, and considered key parameters such as block thickness, spacing. Additionally, the analysis explored the effects of mono and hybrid nanofluids (CuO/Water at 2% volume concentration and CuO + Fe/Water (1% CuO + 1% Fe)) on these novel geometries. The lowest thermal resistance values were measured as follows: Rth = 0.2731 K/W for water fluid, 0.272 K/W for mono nanofluid, and 0.28 K/W for hybrid nanofluid. Based on these results, it was determined that the mono nanofluid exhibited the highest cooling efficiency. Additionally, increasing block thickness and decreasing block distance have a positive effect on thermal resistance in all fluid types and geometries. The temperature distribution of mono-nano fluid is more efficient than that of hybrid-nanofluids and water, resulting in the same effect on thermal resistance. The lowest temperature distribution range was achieved between 310.5 K and 308.16 K in horizontal arrangements. Upon evaluating the system parameters, including thermal resistance, temperature distribution, and Performance Evaluation Criteria (PEC), it was concluded that horizontal arrangements exhibited superior performance compared to vertical ones. The maximum PEC attained was 1.04.