Experimental study on serpentine minichannel heat sink: Effect of rib existence and distance

In this study, experimental investigation on heat transfer and fluid flow characteristics of ribbed maze serpentine minichannel heat sink with different rib distances is conducted. There is rectangular minichannel with 2 mm width and 2mm height. Pure water is employed as working fluid with mass flow rate varied from 0.0017 kg/s to 0.008 kg/s. Three heat sinks with different rib distances (12 mm, 15mm and 18 mm ) are examined and compared with straight and maze serpentine minichannel heat sink without rib. The results show that heat sink base temperature for ribbed maze serpentine minichannel is 13.9% and 7.9% lower than straight and maze serpentine minichannel heat sink, respectively in 0.0017 kg/s. Also, convective thermal resistance is reduced 72% in ribbed maze serpentine minichannel in comparison with straight minichannel heat sink in 0.0017 kg/s. Ribbed maze serpentine minichannels friction factor is greater than friction factor in straight and maze serpentine mini-channel. This study indicates that by increasing rib distance from 12 mm to 18 mm, base temperature decreases 13.8%. Moreover, convective thermal resistance is reduced 14.2% by increasing rib distance from 12 mm to 18 mm, in the lowest mass flow rate. Also, by increasing mass flow rate convective thermal resistance decreases. In the maximum mass flow rate, friction factor is increased 41.2% and 89.4% by increasing rib distance from 12mm to 15mm and 18 mm. The best universal evaluation parameter (PEC) is obtained for the ribbed maze serpentine minichannel heat sink with 18 mm rib distance that has the value of 2.86.