Study on Heat Transfer Characteristics of Matrix Rib Micro-Jet Heat Sink Based on Silicon Carbide Nanofluids

Abstract

Advancements in technology have rapidly developed new energy sources, of which, Photovoltaic technology has evolved into a topic of great interest. An improvement in the performance of concentrated solar cells increases thermal power. During service, temperatures higher or lower than the optimal operating temperature can affect the working state, even causing self-damage. This renders the research on cooling technology for concentrated solar cells a crucial link. The present study has proposed a microfluidic coupled array finned microchannel heat sink for cooling high-power concentrated solar cells, with silicon carbide-water nanofluids as 0.03vol.% the cooling medium. A combination of numerical simulation and experimental methods was used to study the flow and heat transfer characteristics of a radiator. Results indicate that silicon carbide (SiC) nanofluids have a greater cooling effect than water for different height-diameter ratios and heat flow rates of 1568 < Rea < 2618. When the flow rate is 1.7 m/s, the mean heat transfer coefficient of the radiator cooling surface with water is 27863.36 W/(m2.K), whereas the mean heat transfer coefficient of SiC nanofluids is 29661.59 W/(m2.K) under the same operating conditions, an improvement of 6.5%. Compared to water, SiC nanofluids exhibit stronger heat transfer performance, with the average temperature of the cooling surface diminishing by about 2.8%. However, because of the addition of solid particles in SiC nanofluid, the pressure drop of the radiator is slightly higher than that of water cooling. This device’s energy efficiency ratio (EER) ranged between 2–22.3. Comparison of the Nusselt number of the matrix rib microjet heat sink designed in this study with that of the single-use microchannels and microjets revealed that the convective heat transfer intensity was significantly stronger for the matrix rib microjet heat sink, showing its heat transfer advantage. By utilizing a small amount of material, SiC nanofluids have further increased the heat transfer coefficient, signifying the superior heat transfer performance.

Keywords: Concentrated solar cells, Microjet, Nanofluids, numerical simulation, experimental verification