Self-adaptive cooling of chips with unevenly distributed high heat fluxes

The heat load scenario of a real chip is unsteady and spatially variable and gives rise to regions of concentrated high power. Conventional liquid cooling techniques are always inadequate to tailor the flow distribution to the changing thermal environment and cool the resulting high-heat-flux regions effectively. In this work, the self-adaptive cooling for unevenly distributed high heat fluxes is proposed. It contains a matrix of microfluidic units with integrated thermal-sensitive hydrogel valves. The units are independently controlled and deliver the coolant to where it is needed. A numerical model is developed to investigate the flow and temperature distribution of the cooling unit. By introducing the self-adaptive mechanism, the near-wall flow is enhanced remarkably. Nonuniform heat fluxes of up to 460 W/cm2 are effectively dissipated by means of the developed self-adaptive cooling method. The maximum surface temperature drop amounts to 22.6 K, meanwhile the total flow rate can be reduced by nearly an order of magnitude. The microfluidic unit array adapts to local heat fluxes by reconfiguring its internal flow-channel structure automatically and thus movable hotspots are elaborately cooled. The self-adaptive cooling scheme offers both effective and smart thermal management for modern electronic devices.