Pumping effects due to reciprocating asymmetric baffles

A significant pumping effect at low differential head can be achieved by oscillating one or more asymmetric baffle plates in a tube. The resistance to backflow of fluid relative to the plates is affected by the direction of movement of the plates, for a given plate speed. This effect has been demonstrated in a 5 cm dia. tube, using an air-driven plate assembly at frequencies from 0.5 to 2.25 Hz and strokes from 10 to 25 cm. The forms of the characteristic curves for a given baffle geometry depend on the frequency and stroke of operation. It is concluded that this type of pump could be used for very abrasive or fibrous fluids where the head and delivery rate requirements are relatively low.