STUDY OF EFFECT OF VISCOSITY RESISTANCE IN ELECTROFHEOLOGICAL FLUID BY MICRO GRAVITY EXPERIMENTS

我们首次从微重力实验中观察到了由单分散介质颗粒组成的单相电流变悬浮液中的电流变(ER)效应。设计了一台高灵敏度的电流变仪用于测量，结果表明，在微重力环境下，颗粒在没有悬浮液的情况下可以形成稳定的单相悬浮液，这是传统电流变液通常所必需的。实验发现，颗粒形成的柱状结构尺寸超过了通常在两相电流变流体中观察到的最大柱宽。采用有限元方法对电能密度随应变的变化进行了数值计算，计算结果与测量数据吻合较好，特别是在低场区。

We reported the first observation of electrorheological(ER) effect in a single phase ER suspension, comprising mono-dispersed dielectric particles, from a microgravity experiment. A highly sensitive electro-rheometer was designed for the measurements and the results show that, in the microgravity environment, the particles can form stable single phase suspension without a suspending liquid, which is usually necessary for the conventional ER fluid. It is found from the experiments that the size of the column structures formed by the particles exceeds the maximum column width usually observed in the two-phase ER fluids. Finite element method(FEM) was used to evaluate numerically the variation of the electric energy density with respect to the strain, and the results yield a good account of the measured data, especially in the low field region.