APPLICATIONS OF COLD PLATE UNITS WITH MICRO-CHANNEL FOR COOLING ELECTRONICS

Until recently, effective cooling solutions with high performance were required especially in data-centers and super computers because of the huge and ever-increasing power consumption in these applications. Water cooling systems have been considered for use in the cooling of large scale data-centers and super computers. For the cooling of super computer CPUs, a water cooling system using advanced cold plate technology is reconsidered. The thermal resistance of a cold plate for cooling the CPU is required to dissipate 80 to 100W of heat at 0.05 K/W. Also, in this application, the cold plate is required to be mechanically reliable in withstanding a cooling water pressure of 1MPa. We adopted a micro-channel structure as a heat transfer surface of this cold plate and developed a new brazing method so that the tips of the micro-channel fins are bonded to the inside of cover plate of the cold plate. In collaboration with a customer in charge of the design, we completed the water cooling unit consisting of cold plates, pipes and coupler manifold, assembled by brazing. Finally, the high volume products were manufactured with reliability inspection (pressure test and helium leakage test) and used to effectively cool the CPUs of an advanced super computer, which was awarded the fastest super computer record. Water cooling technology provides effective high capacity cooling in compact space limits, and has been widely used in applications like fiber laser machines and others. This paper describes the development of cold plate with micro-channels and its applications.