Study of particle-fluid interaction and thermal effects in dielectrophoretic microfilters

Dielectrophoretic filters are based on particles migration in non-uniform electric fields and are used for separation and detection of cells or microorganisms suspended in liquid media. In this paper, interaction between particles moving under dielectrophoretic effect and pressure driven flow of fluid is modelled and introduced in momentum equation as reaction body force depending on electric field and particle concentration. The basic configuration of microfilter with castellated electrodes and flow channel was simulated. The electric field distribution obtained by electrostatic simulation was used in equations that solve the particle-fluid solution flow. Thermal effects of Joule heating on material parameters were also studied. The numerical results show that dieletrophoretic migration of particles and the velocity of fluid media have reciprocal influence and have to be solved in a coupled approach.