电流变液中的电导率效应研究

The study of effects of conductivity in electrorheological fluids

基于 Maxwell Wagner模型 ,推广基于多极展开原理的 Rayleigh方程研究电流变体系的电导率效应 .计算了其有效介电常数和剪切模量 .结果发现颗粒球为导体时颗粒间相互作用力对它们间的距离十分敏感 ;在高频率外场作用下 ,体系剪切模量仅由颗粒和液体的介电常数决定而与其电导率无关 ;在低频率外场作用下 ,体系剪切模量则由颗粒和液体的电导率决定 .

Rayleigh identity based on a multipole expansion theory is extended to analyze the conductivity effects in electrorheological system within a MaxwellWagner approach. Evaluation of the effective dielectric constant is emphasized and shear modulus for chains of particles arrayed on a square lattice is calculated.It is found that the particle particle forces are extremely sensitive to their separation if the particle has infinsty conductivity.It is found too that for high frequency applied electric fields, the forces and then the modulus depend upon the dielectric constants of the suspending fluid and the dispersed particles, for low frequency or dc electric fields, the conductivities of the components are dominant.