Tian Yu, Wen Shizhu, Meng Yonggang
State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, People's Republic of China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2003 May;67(5 Pt 1):051501. doi: 10.1103/PhysRevE.67.051501. Epub 2003 May 14.
Compressions of electrorheological (ER) fluids have been carried out under different initial gap distances and different applied voltages. The nominal yield stresses of the compressed ER fluid under different conditions, according to the mechanics of compressing continuous fluids considering the yield stress of the plastic fluid, have been calculated. Curves of nominal yield stress under different applied voltages at an initial gap distance of 4 mm overlapped well and were shown to be proportional to the square of the external electric field and agree well with the traditional description. With the decrease of the initial gap distance, the difference between the nominal yield stress curves increased. The gap distance effect on the compression of ER fluids could not be explained by the traditional description based on the Bingham model and the continuous media theory. An explanation based on the mechanics of particle chain is proposed to describe the gap distance effect on the compression of ER fluids.
在不同的初始间隙距离和不同的外加电压下对电流变（ER）流体进行了压缩。根据考虑塑性流体屈服应力的连续流体压缩力学，计算了不同条件下压缩后的ER流体的名义屈服应力。在初始间隙距离为4mm时，不同外加电压下的名义屈服应力曲线重叠良好，并且显示出与外部电场的平方成正比，与传统描述吻合良好。随着初始间隙距离的减小，名义屈服应力曲线之间的差异增大。基于宾汉模型和连续介质理论的传统描述无法解释间隙距离对ER流体压缩的影响。提出了一种基于粒子链力学的解释来描述间隙距离对ER流体压缩的影响。
