电流变液颗粒间局部电场分析及相互作用力计算

Particle-particle Local Electric Field Analysis and Interaction Force Calculation in Electrorheological Fluids

电流变(electrorheo logical,ER)液可用于直接驱动电动机、离合器、无级变速、机械装置的电控等领域,如何准确计算电流变液体成链过程中的颗粒间相互作用成为研究热点。介绍了计算电流变液中多颗粒间局部电场及相互作用力的新模型—偏心电偶极子模型,分析了偏心电偶极子模型的理论基础,研究将其用于计算电流变液体中多颗粒间局部电场及相互作用力的方法。将颗粒间局部电场计算结果与点电偶极子及有限元方法的计算结果进行对比。通过比较可知,偏心电偶极子模型计算结果与有限元计算结果最为接近,优于点电偶极子模型。同时给出用于计算三颗粒间局部电场及相互作用力的公式,并与同等条件下的两颗粒间相互作用力进行对比,结果表明,在一定条件下两颗粒的相互作用力高于三颗粒的相互作用力,这说明颗粒在聚集成链的过程中初期的相互作用力可能要高于后期。

Electrorheological （ER） fluids have been applied in electronic control,such as direct drive motor,clutch,continuously variable transmission system and mechanical device,how to accurately calculate the interaction force of particles in the process of forming chains in the electrorheological fluids has become a research focus. In this paper,a new displaced dipole for calculating local electric field and interaction force of the particles in electrorheological fluids was proposed. The theory of displaced dipole model was analyzed,and the method applied to calculate the local electric field and interaction force in the electrorheoloigcal fluids was studied. The results indicate that the displaced dipole model has better performance than the dipole model,the result got by former method is more close to the result got by finite element method （FEM）. A new formula used to calculate local electric field and interaction force among three particles was also proposed. The calculating result shows that interaction force among three particles is lower than that between two particles in some condition,which indicates that the interaction force of particles in the early stages may be higher than that in the later stages in the process of chains formation.