Rotating Electroosmotic Flow At High Zeta Potentials In Microhannel

Microfluidic device,an equipment used to control fluid,is widely used in biochemical analysis and microelectronic systems,etc.electroosmosis actuation with its flexible control,simple structure and high efficiency advantages becomes dominant actuation technology in the microfluidic device.Rotating electro-osmotic flow of Newtonian fluid in a microchannel of two parallel plates is investigated.Under the conditions of a thin electric double layer,the charge density distribution is obtained by using nonlinear Poisson-Boltzmann equation.The analytical solution of velocity and flow rate got from the reduced Navier-Stokes equation under rotating coordinates by constant variation.In addition,the results by numerical integration with the low zeta potential are compared.The influences of the dimensionless wall Zeta ?₀,rotating angular velocity ? and electrokinetic width Kon velocity profiles are presented.The results show that the fluid of far away from electric double layer is more easily affected by rotation,resulting in electroosmosis velocity profile to form a concave in the center of the microchannel.Compared with low Zeta potential,high Zeta potential could promote fluid flow and enhance the electroosmotic velocity.In addition,the influences of the dimensionless wall Zeta ?₀ and rotating angular velocity ? on flow rate are presented.