Experimental investigation on heat transfer characteristics of an oblique finned microchannel heat sink with different channel cross sections

The heat transfer and flow characteristics of oblique finned microchannel heat sink with a dimension of 48 × 80 mm2 were investigated experimentally with different channel cross-sections. The three-channel cross sections were namely trapezoidal, square and semi-circle is analyzed by using Al2O3/water nanofluid with 0.25% volume fraction and water as a coolant. The experiments were performed with a constant mass flow rate of 0.1 LPM and varying heat flux ranging from 5.5 to 26.5 kW/m2. The temperature and pressure drop across the inlet and outlet of the microchannel heat sink were measured to obtain heat and flow characteristics. The result shows that trapezoidal cross-section performs better and it provides 8.5 and 10.3% increased heat transfer rate than square and semi-circle cross sections respectively. Similarly, it gives 6.6 and 8.2% increase in friction factor than square and semi-circle respectively. Also, the case with trapezoidal cross-section creates lesser thermal resistance and slightly higher pumping power among the three sections.