Miniature single-disk viscous pump (single-DVP), performance characterization

The development and testing of a rotating single-disk viscous pump are described. This pump consists of a 10.16 mm diameter spinning disk, and a pump chamber which are separated by a small gap that forms the fluid passage. The walls of the pump chamber form a C-shaped channel with an inner radius of 1.19 mm, an outer radius of 2.38 mm, and a depth of 40, 73, 117, or 246 am. Fluid inlet and outlet ports are located at the ends of the C-shaped channel. Experimental flow rate and pressure rise data are obtained for rotational speeds from 100 to 5000 rpm, fluid chamber heights from 40 to 246 mu m, flow rates from 0 to 4.75 ml/min, pressure rises from 0 to 31.1 kPa, and fluid viscosities from 1 to 62 mPa s. An analytical expression for the net flow rate and pressure rise, as dependent on the fluid chamber geometry, disk rotational speed, and fluid viscosity, is derived and found to agree with the experimental data. The flow rate and pressure rise of the pump vary nearly linearly with rotational speed. The volumetric flow rate does not change significantly with changes in fluid viscosity for the same rotational speed and pumping circuit. Advantages of the disk pumps include simplicity, ease of manufacture, ability to produce continuous flow with a flow rate that does not vary significantly in time, and ability to pump biological samples without significant alteration or destruction of cells, protein suspension, or other delicate matter.