芯片冷却用分形微管道散热器内的压降与传热

Pressure Drop and Heat Transfer in Fractal Microchannel Heat Sinks for Cooling of Electronic Chips

受到哺乳动物消化系统和血液循环系统中物质运输与分配网络所具有的分形特征启发 ,文中设计、加工出了一种电子芯片冷却用的硅制分形微管道网络散热器 .在给出分形微管道网络构造过程的基础上 ,探讨了分形微管道网络内部微流体的换热与压力降特性 .针对利用多路感应耦合等离子蚀刻工艺制造出的硅制分形微管道网络散热器 ,理论计算所得结论与流动与传热实验数据均证明 :当热传递面积、温差、努谢尔特数均相同的情况下 ,分形微管道网络散热器比传统的平行微管道阵列散热器具有更高的热传递效率 ;而在具有相同流速、热传递率的要求下 ,分形微管道网络散热器所需的泵送功率远低于平行微管道阵列散热器所需的泵送功率 ;分形维数越高 ,分形微管道网络散热器的热传递效率将越高 ,且所需的泵送功率将越低 .

Inspired by the fractal pattern of mammalian digestive and circulatory system, a magical design of fractal branching channel heat sinks for cooling of electronic chips is studied. Based on the fractal branching net constructing, the heat transfer and pressure drop characteristics of fluid flow in fractal microchannel net are investigated. Furthermore, the fractal tree-like microchannel heat sinks are fabricated by multiplex inductively coupled plasma etching equipment in silicon wafer. The theoretical calculation and heat transfer experiments show that the fractal channel net has a higher heat transfer rate compared with the parallel channels having the same heat transfer condition and Nusselt number, the required pumping power for fractal channel net is decreased compared with parallel channels having the same velocity and heat transfer rate. Specially, the fractal channel net with larger dimensions can achieve higher heat transfer rate and lower pumping power on the same analyzed conditions.