Ultrasonic pump with non-planar transducer for generating focused longitudinal waves and pumping methods

摘要

An ultrasonic pump in which a medium is pumped by the interaction between longitudinal acoustic waves and the medium in a flow-chamber. The pump comprises a non-planar, transducer and an associated chamber for providing a controllable, focused, acoustic traveling wave therein. The chamber includes a tapered passage corresponding to the focused beam pattern of the focused acoustic traveling wave through which the liquid medium flows and/or cavitation is induced and/or controlled. The pump therefore utilizes a focused, non-planar, acoustical transducer responsive to frequency input for directing longitudinal acoustic waves into the flow-chamber which induces a pressure gradient. The medium in the flow-chamber flows in the direction of travel of the acoustic wave in the chamber as a result of acoustic streaming. The exit orifice of the nozzle in communication with the chamber is strategically located at about the focal zone of the focused, traveling wave. Thus, the pump provides ultrasonic control of a medium to provide selective motion and cavitation.