A piezo-electric pump driven by a flexural progressive wave

An effort was made to confirm the possibility of pumping fluids by flexural progressive waves on a thin pipe. A piezoelectric ceramic plate whose composition changes periodically can generate a flexural progressive wave when two sinusoidal voltages (V/sub 0/ sin omega t and V/sub 0/ cos omega t) are applied. A thin metal pipe that has been flattened is bonded to an FGM piezoelectric ceramic plate. Both ends of the pipe are closed and two glass pipes are joined perpendicularly to the metal pipe. The pipes are then filled with purified water. When a flexural progressive wave is excited on the plate, pressure is generated between the glass pipes. The pressure is about 10 mm H/sub 2/O. When the phase difference between the two sinusoidal voltages is changed by 180 degrees , the pressure difference is inverted. The size of the plate is 230*50*0.6 mm/sup 3/, the diameter of the metal pipe is 1.4 mm, the thickness of the wall is 18 mu m, and the pipe is flattened to 300 mu m.<>