An experimental study on hydrothermal performance of microchannel heat sinks with 4-ports and offset zigzag channels

For cooling specific chip of 2 mm∗10 mm, the 4-ports and offset zigzag microchannels are designed. The fluid flow and heat transfer characteristics of 4-ports silicon heat sinks with rectangle and zigzag microchannels have been investigated experimentally. Deionized water is employed as the cooling fluid with flow rates of 28-72 ml/min. Results show the 4-ports heat sink can effectively reduce pressure drops and reduce temperature rising along the flow directions for the fixed flow rates. For 4-ports with rectangle microchannel, the pressure drops is decreased about 70% and average temperature also is reduced by 2.8 °C. It can be interpreted that 4-ports structures reduce the length of channel and increase channel number, which leads to the flow velocity decreased by 0.5 times and the fluid distribution more uniform. Compared with 4-ports with rectangle microchannels, for 4-ports with zigzag microchannels heat sink, the pressure drop is reduced under the lower flow rates but increased slightly under larger flow rates. And temperatures of all flow rates are reduced, which is reduced by 3.8 °C and pressure drop only increased 2.6 kPa at flow rates of 72 ml/min. It can be interpreted that zigzag cavities redevelop thermal boundary layer and enhance the fluid disturbance to make the fluid mixing better. Additional, zigzag cavities also enlarge heat transfer areas and reduce the fluid velocity by increasing flow cross-section areas. Under fixed pumping power, 4-ports with Z can meet the larger heat dissipation and smaller flow rates requirement.