Intellectual Textile System Research Center (ITRC) and School of Materials Science and Engineering, College of Engineering, Seoul National University, Shillim9dong 56-1, Kwanakgu, Seoul, 151-744 Republic of Korea.
Langmuir. 2012 Feb 14;28(6):3077-84. doi: 10.1021/la204515q. Epub 2012 Jan 31.
A model capable of describing the flow behavior of electrorheological (ER) suspensions under different electric field strengths and over the full range of shear rates is proposed. Structural reformation in the low shear rate region is investigated where parts of a material are in an undeformed state, while aligned structures reform under the shear force. The model's predictions were compared with the experimental data of some ER fluids as well as the CCJ (Cho-Choi-Jhon) model. This simple model's predictions of suspension flow behavior with subsequent aligned structure reformation agreed well with the experimental data, both quantitatively and qualitatively. The proposed model plausibly predicted the static yield stress, whereas the CCJ model and the Bingham model predicted only the dynamic yield stress. The master curve describing the apparent viscosity was obtained by appropriate scaling both axes, which showed that a combination of dimensional analysis and flow curve analysis using the proposed model yielded a quantitatively and qualitatively precise description of ER fluid rheological behavior based on relatively few experimental measurements.
提出了一种能够描述不同电场强度下电流变(ER)悬浮液流动行为并涵盖全剪切速率范围的模型。研究了低剪切速率区域的结构重组,其中材料的一部分处于未变形状态,而在剪切力作用下,对齐结构会发生重组。模型的预测结果与一些 ER 流体的实验数据以及 CCJ(Cho-Choi-Jhon)模型进行了比较。该简单模型对悬浮液流动行为及其后续对齐结构重组的预测与实验数据在定量和定性上都非常吻合。所提出的模型合理地预测了静态屈服应力,而 CCJ 模型和宾汉姆模型仅预测了动态屈服应力。通过适当缩放两个轴获得了描述表观粘度的主曲线,这表明通过使用所提出的模型进行尺寸分析和流动曲线分析的组合,可以基于相对较少的实验测量,对 ER 流体流变行为进行定量和定性的精确描述。