Thermal Characteristics of Staggered Double-Layer Microchannel Heat Sink.

The present work numerically studies the thermal characteristics of a staggered double-layer microchannel heat sink (DLMCHS) with an offset between the upper layer of microchannels and lower layer of microchannels in the width direction, and investigates effects of inlet velocity and geometric parameters including the offset of the two layers of microchannels, vertical rib thickness and microchannel aspect ratio on the thermal resistance of the staggered DLMCHS. The present work found that the thermal resistance of the staggered DLMCHS increases with the increasing offset value when the vertical rib thickness is small, but decreases firstly and then increases as the offset value increases when the vertical rib thickness is large enough. Furthermore, the thermal resistance of the staggered DLMCHS decreases with the increasing offset when the aspect ratio is small, but increases with the increasing offset when the aspect ratio is large enough. Thus, for the DLMCHS with a small microchannel aspect ratio and large vertical rib thickness, the offset between the upper layer of microchannels and the lower layer of microchannels in the width direction is a potential method to reduce thermal resistance and improve the thermal performance of the DLMCHS.

本研究对在宽度方向上微通道上层和下层之间存在偏移的交错双层微通道热沉（DLMCHS）的热特性进行了数值研究，并探讨了入口流速以及包括两层微通道的偏移量、垂直肋厚度和微通道纵横比在内的几何参数对交错式DLMCHS热阻的影响。本研究发现，当垂直肋厚度较小时，交错式DLMCHS的热阻随偏移量值的增加而增大，但当垂直肋厚度足够大时，热阻随偏移量值的增加先减小后增大。此外，当纵横比小时，交错式DLMCHS的热阻随偏移量的增加而减小，但当纵横比足够大时，热阻随偏移量的增加而增大。因此，对于具有小微通道纵横比和大垂直肋厚度的DLMCHS，在宽度方向上微通道上层和下层之间的偏移是一种降低热阻并提高DLMCHS热性能的潜在方法。