Evaluation of a Liquid Cooling Concept for High Power Processors

A high performance liquid cooling architecture for high power processors in less than 45 mm height electronics chassis (1U rack space) was proposed and investigated experimentally. A review of several system cooling approaches from CPU to data center was also provided. The present proposed method employs conventional heat pipes to transport local CPU heat to the edge of an electronics module coupled with system liquid cold plates. As coolant from external cooling distribution unit in data center flows through the system cold plates in the rack, CPU heat load is rejected to data center cooling facility. Capable of removing the processor power as high as 450W is demonstrated from a prototype built. Experiments were conducted to characterize the prototype thermal performance between liquid inlet and heat pipe evaporator base. A 25 mm times 25 mm heat block was used to simulate CPU and provide heat source to the heat pipe evaporator base. The impacts of heat transfer rate, flow rate, and liquid inlet temperature were evaluated. The total thermal resistance of below 0.090degC/W was achieved at water flow rate of 1 l/min and heat transfer rate of 450W.