提出了双层微通道热沉两种新的流动方式，逆流 CB-DL（逆流 B 形式）与逆流 CC-DL（逆流 C 形式），并用数值模拟的方法研究这两种流动方式对热沉整体温度分布及传热性能的影响。结果表明：与流动方式顺流 P-DL 与逆流 CA-DL 对比，采用CB-DL 流动方式时，热沉底面温度先升高后下降，温度最高点集中在热沉的中部，温度分布相对均匀；而且当泵功 PP ＞0．05 W时，与其他入口流动方式对比，采用逆流 CB-DL 的底面温差及热阻最小，这是由逆流 CB-DL 的流动特点决定的，当流体流入上层通道时，由于上层流体带走的热量小于下层的，流体受热温度稍微提高，这时上层受热温度升高的流体流入下层，减小了下层流体的入口温度与底面温度的温差，因而有效地减少流体与底面温度的不可逆损失，从的角度说明有效提高了热能的利用率。%To study the heat transfer performance of enhanced heat transfer process in microchannel heat sinks,two novel flow manners of a double-layer micro heat sink are presented,i.e.,counter flow CB-DL and CC-DL.The effect of total temperature distribution and heat transfer performance on them is investigated numerically.Results show that for counter flow CB-DL,the bottom temperature increases firstly and then decrease along the flow direction,thus the maximum temperature is located at the middle of the heat sink.Compared with flow manners,the temperature difference and thermal resistance are minimum when PP<0.05 W.The reason is that the lower-layer microchannel can remove more heat than the upper-layer microchannel,thus resul-ting in a little temperature rise of the lower-layer fluid.This can help to reduce the temperature difference between the inlet tem-perature of the lower-layer fluid and the bottom temperature,thereby helping to decrease the irreversibility caused by fluid flow and the bottom temperature.Form the view point of exergy,it is favorable to improve the utilization of heat.
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