Pressure drop of single phase flow in microchannels and its application in characterizing the apparent rheological property of fluids
Pressure drop of single phase flow in microchannels and its application in characterizing the apparent rheological property of fluids
复制标题
微通道内单相流压降及其在表征流体表观流变特性中的应用
DOI：
10.1007/s10404-019-2241-y
复制
发表时间：
2019
影响因子：
2.8
通讯作者：
Ma Youguang
中科院分区：
文献类型：
--
作者：
Yang Xiaohan;Weldetsadik Netsanet Tesfaye;Hayat Zafar;Fu Taotao;Jiang Shaokun;Zhu Chunying;Ma Youguang
这项工作的目的是通过实验检查微通道中基于压降的流体的表观流变特性。使用压力传感器测量微通道中牛顿和非牛顿流体的压降。研究了流量、雷诺数和流体粘度对微通道内单相流压降的影响，并将压降测量值与预测模型进行了比较。对于牛顿流体，层流区域的摩擦系数为f/2 = 26/Re。结果表明，牛顿流体的压降与Cornish提出的预测公式吻合较好。然而，非牛顿流体的压降与理论预测存在偏差。基于压降测量，提出了非牛顿流体的表观粘度与微通道中特征剪切速率之间关系的幂律。由于非牛顿流体在微通道中流动时，剪切速率在径向上的不均匀分布，特定微通道中表观粘度与特征剪切速率之间的关系与锥板流变仪测量的流变曲线完全不同。
The aim of this work was to experimentally examine apparent rheological properties of fluids in microchannels based on pressure drop. Pressure drops of Newtonian and non-Newtonian fluids in microchannels were measured using pressure sensors. The effects of flow rate, Reynolds number, and viscosity of fluids on the pressure drop of single phase flow in microchannels were investigated, and the measurements of pressure drop were compared with prediction models. For Newtonian fluids, the friction factor in the laminar regime isf/2 = 26/Re. The results show that the pressure drop of Newtonian fluid is in good agreement with the prediction formula proposed by Cornish. However, the pressure drop of non-Newtonian fluid deviates from the theoretical prediction. A power-law is proposed for the relationship between the apparent viscosity of non-Newtonian fluid and the characteristic shear rate in a microchannel based on the pressure drop measurement. This relationship between the apparent viscosity and the characteristic shear rate in a specific microchannel is completely different from the rheological curve measured by cone-and-plate rheometer, due to the heterogeneous distribution of shear rates at the radial direction for non-Newtonian fluids flowing in a microchannel.