Experimental investigation of microchannel heat sink performance under non-uniform heat load conditions with different flow configurations

Cooling methods for multiple hotspots with high heat flux pose a reliability threat to electronic devices. This study investigates the microchannel-based heat sink performance under various non-uniform heat load conditions for different geometry with three different flow configurations (I, U and Z). An in-house designed Heater Array Unit (HAU) facilitates the generation of both uniform and non-uniform heat loads using a heater power supply. Two different microchannel geometries were employed, namely, microchannel-1 (MC-1) with channel and fin widths of 0.6 mm and 0.33 mm, respectively, and MC-2 with dimensions of 0.64 mm and 0.572 mm. Each microchannel incorporates three manifold configurations (I, U, and Z). Each flow configuration is regulated by flow control valves . Various non-uniform heat load patterns were considered, including streamline, non-streamline, and across-streamline conditions. To assess the thermal performance of the heat sinks the parameters used are thermal resistance (R th ), Nusselt number ( Nu ), and temperature non-uniformity (Ѱ). Experimental findings indicate that the MC-2 design with an I flow configuration is more suitable for uniform heat load conditions. On the contrary, for some non-uniform heat load cases MC-1 also showed up as a suitable design over MC-2. • Experiments were conducted on two microchannel designs (MC-1, MC-2) with three different flow configurations (I, U and Z). • Uniform heat load case, MC-2 design exhibited a 17.8% lower thermal resistance compared to MC-1 with an I-type flow. • In hotspot case #167, the MC-2 design has a 16% higher Nusselt number than the MC-1 design. • Temperature non-uniformity is significantly varies with respect to the non-uniform heat load.