Research On Liquid Cooling Performance Of Multilayer Fractal Microchannel Heat Sink

Rapid developments in high power and density chips have led to the electrical components with a serious heating problem. It will affect the reliability of chips, causes function failure and device deformation, decrease the working life. Under for this situation, thermal design is critical and significantly in the electronics structure design. Hence, a multi-layer and complicated structure of microchannel heat sinks with the characteristic of small size, lower pressure drop and high cooling efficiency shows the broad application prospects in this areas, which can ensure the operation reliable and satisfy heat dissipation requirements.This paper are based on the design thought of multi-layer and single bifurcate symmetrical microchannel structure, we use some bionics theories to do theoretical derivation, analyzing two important parameters: channel aspect ratio of microchannel and bifurcation angle. The bifurcate Angle of 50°(ideal) and 180° microchannel structures is designed, and at last, we have designed the overall structure of the multi-layer microchannel heat sink. On this basis, according to single bifurcate symmetric structure of microchannel heat sink, we put forward an approximate method of calculating the thermal resistance(thermal resistance network model), a good agreement with the simulations.The multi-layer heat sink model is constructed by the PRO/E and the simulation is also calculated by using the fluid dynamics finite element analysis software FLUENT modules of the workbench 12.0. According to the comparison of temperature, speed, pressure under different flow rate, the two different bifurcation angle of the three layers microchannel heat sink is analyzed. And the optimal bifurcation angle of the microchannel structure has the better flow efficiency and heat dissipation performance. Meanwhile, we analysis and compare the 50 ° bifurcation angle heat dissipaiton performance of 1-5 layers microchannel heat sink through pressure drop through unit, specific thermal resistance, thermal resistance, pump power numerical diagrams under the condition of different inlet flow rate.Finally, we construct the experimental test platform, process three layers heat sinks of two different bifurcation angle, choose reasonable and applicable laboratory equipment instruments and carry out experimental measurement. Combined with the experimental data, we obtain the optimal bifurcation angle three layers microchannel heat sink with smaller thermal resistance, lower system pressure drop. Also it is verified that the overall heat dissipation performance of 50°bifurcate angle microchannel radiator is better.