Although roughness is negligible for laminar flow through tubes in classic fluid mechanics, the surface roughness may play an important role in microscale fluid flow due to the large ratio of surface area to volume. To further verify the influence of rough surfaces on microscale liquid flow and heat transfer, a performance test system of heat transfer and liquid flow was designed and built, and a series of experimental examinations are conducted, in which the microchannel material is stainless steel and the working medium is methanol. The results indicate that the surface roughness plays a significant role in the process of laminar flow and heat transfer in microchannels. In microchannels with roughness characteristics, the Poiseuille number of liquid laminar flow relies not only on the cross section shape of the rough microchannels but also on the Reynolds number of liquid flow. The Poiseuille number of liquid laminar flow in rough microchannels increases with increasing Reynolds number. In addition, the Nusselt number of liquid laminar heat transfer is related not only to the cross section shape of a rough microchannel but also to the Reynolds number of liquid flow, and the Nusselt number increases with increasing Reynolds number.

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粗糙微通道中液体流动与传热的实验研究

尽管在经典流体力学中，层流通过管子的粗糙度可以忽略不计，但由于表面积与体积的大比例，表面粗糙度可能在微尺度流体流动中起重要作用。为了进一步验证粗糙表面对微尺度液体流动和传热的影响，设计并搭建了传热和液体流动性能测试系统，并进行了一系列实验检验，其中微通道材料为不锈钢，工作介质为甲醇。结果表明，表面粗糙度在微通道层流和传热过程中起着重要作用。在具有粗糙度特征的微通道中，液体层流的泊肃叶数不仅取决于粗糙微通道的横截面形状，还取决于液体流动的雷诺数。粗糙微通道中液体层流的泊肃叶数随着雷诺数的增加而增加。此外，液体层流传热的努塞尔数不仅与粗糙微通道的横截面形状有关，还与液体流动的雷诺数有关，努塞尔数随着雷诺数的增加而增加。