Direct simulation of electrorheological suspensions

A numerical scheme based on the distributed Lagrange multiplier method (DLM) is used to study the motion of particles of a dielectric suspensions subjected to uniform and nonuniform electric fields. The Maxwell stress tensor method is used for computing electrostatic forces. In the point dipole approximation the total electrostatic force acting on a particle can be divided into two distinct contributions, one due to dielectrophoresis and the second due to particle-particle interactions. The former is zero when the applied electric field is uniform and the latter depends on the distance between the particles. In the Maxwell stress tensor approach these two contribution appear together. Simulations show that as expected the error in the point dipole approximation decreases, as the distance between the particles increases.