Analysis of double-chamber parallel valveless micropumps

The characteristics of a double-chamber valveless parallel micropump are analysed using a one-dimensional non-linear model. The relationships between the mean volume flux, pressure difference and (measurable) characteristics of the pump are derived in a closed-form expression which are validated against the numerical solutions. These results show that when pump chambers are driven exactly out of phase, the volume flux is maximum and the variation of the pump chamber pressure is (significantly) reduced. The model predictions were tested against the experimental results of Olsson et al. (Sens Actuators A Phys 47:549-556, 1995) for both in and out of phase pumps. The mean volume flux decreases linearly with pressure rise. For both cases, the agreement is good and is an improvement over previous analytical models. The implications of these results for optimal pump design are discussed.