Numerical Study of Single-Layer and Stacked Minichannel-Based Heat Sinks Using Different Truncating Ratios for Cooling High Concentration Photovoltaic Systems

The present research aims to discuss and analyze the performance of truncated single-layer and stacked mini-channel-based heat sinks employed for the cooling of a single-cell high concentrating photovoltaic systems. The truncating technique of the fins at the entrance and exit regions from the internal fluid mini channels is opted to reduce the energy, raw material costs and time of the manufacturing process of the mini channels. This proposed solution is constrained by several metrics such as the thermal management and the overall performance of the high concentrating photovoltaic system. In the current research, the use of a truncating ratio of 31% has yielded minimum cell temperature and maximum electrical efficiencies for both single-layer and stacked mini-channel-based heat sinks, while a truncating ratio of 65% has enabled more uniform cell temperature distribution. Moreover, a truncating ratio of 65% has qualified the highest water outlet temperature and the lowest pressure drops relatively compared to the conventional mini-channel-based heat sink configurations. The highest water temperature has reached up to 52.7 °C by the stacked mini-channel-based heat sink with a truncating ratio of 65% under a geometrical concentration ratio of 2000× and a mass flow rate of 0.001 kg s⁻¹ . For both the single-layer and stacked mini-channel-based heat sinks, the use of a truncating ratio of 65% has driven the upper hands to achieve higher ratio of the thermal power to the pumping power (RTP). The maximum RTP values have been recorded by the single-layer mini-channel-based heat sink with a truncating ratio of 65% equal to 23.61 × 10⁶ and 233.06 × 10³ at a mass flow rate of 0.008 kg s⁻¹ and 0.001 kg s⁻¹, respectively, under 2000×.