Simple analytical expressions for the flow performance of a spiral-channel viscous micropump

The paper presents several new simple expressions for the flow performance of a spiral channel viscous micropump. The expressions are based on an analytical stream function solution for the flow field in the spiral cavity of the pump which neglects the curvature of the spiral channel and replace it with an equivalent straight channel with appropriate dimensions and boundary conditions. Solution results relate the flow rate, torque and power consumption of the spiral pump to the pressure difference and rotation rate. Finite volume numerical simulations of the complete Navier-Stokes equations for the 3D flow field in the pump were used in verifying the assumptions employed in the analytical model, and the expressions developed.