【摘要】 随着航天器功能部件热流密度激增,相关电子设备的寿命和可靠性面临着严峻的散热问题.将微通道散热技术与高导热金刚石/铜复合材料相结合,为解决航天器的散热难题提供了有效途径.本文设计了一种分体式金刚石/铜微通道散热系统,并与纯铜微通道系统对比.以HFE-7100为工质,研究了不同流速、不同肋高下两种微通道系统的传热特性.当流速为0.7 m·s^–1,随着肋高的增加,临界功率下金刚石/铜比纯铜微通道系统的芯片表面温度低12, 19, 19.6℃,传热系数最大提升分别为27.8%, 30.1%, 28.1%.两种微通道系统的压差在对流段几乎相同,进入核态沸腾后,金刚石/铜微通道系统压差整体略高,最大增加了11.8%.更多还原

【Abstract】 With the development of aerospace technology, the intelligence level of spacecraft is increasing day by day. The increasing demand for chip computing power leads to a significant increase in its heat flux density, and the life and reliability of related electronic devices are facing severe heat dissipation challenges. The combination of microchannel heat dissipation technology and high thermal conductivity diamond/copper composites provides an effective way to solve the heat dissipation challenges of spacecraft. In view of the poor machinability of diamond/copper composites, a split diamond/copper composite microchannel heat dissipation system is designed in this paper and compared with a pure copper microchannel system. The heat transfer characteristics of the two microchannel systems at different flow rates(0.3, 0.5, 0.7 m·s^–1) and rib heights（1, 1.5, 2 mm） were investigated using HFE-7100 as the heat transfer medium. When the flow rate is 0.7 m·s^–1, the chip surface temperatures of diamond/copper microchannels at the critical power are lower than those of pure copper microchannels by 12℃, 19℃,and 19.6℃, respectively, with the increase of rib height. The heat transfer coefficients were maximally enhanced by 27.8%, 30.1%, and 28.1% at the three rib heights, respectively, showing the heat dissipation advantages of the diamond/copper composite microchannels. The better heat transfer performance of the diamond/copper composite microchannel system is mainly due to its higher thermal conductivity and surface roughness. The pressure drop between the inlet and outlet of the two microchannel systems is basically the same in the single-phase flow section, and the difference gradually becomes apparent when entering nucleate boiling. At critical power, the pressure drop of the diamond/copper microchannel system is slightly higher than that of the pure copper microchannel system, with a maximum increase of 11.8%. The reason for the higher pressure drop in the diamond/copper microchannel system is that the turbulence level of the working fluid is higher in the diamond/copper microchannel system.更多还原