Abstract: A portable, non-invasive flowmeter for a partially filled pipe includes a Doppler shift velocity sensor and a level sensor, each of which has an ultrasonic transducer which is releasably attached to the outside of the pipe out of communication with the interior thereof. The transducers are coupled to a control console which includes a microprocessor which alternately operates the velocity and level sensors to produce flow and level signals respectively indicative of the fluid flow velocity and the filled cross-sectional area of the pipe and calculates the rate of fluid flow from the velocity and level signals.

Abstract: An ultrasonic impeller flowmeter for measuring fluid flow through a conduit includes a paddle wheel impeller rotatably mounted in a cylindrical protective housing which extends radially into the conduit through an aperture therein. A diametrical slot through the distal end of the housing admits fluid to rotate the paddle wheel. Ultrasonic transducers are embedded in the housing on opposite sides of the paddle wheel for establishing an ultrasonic carrier signal. Circumferentially spaced-apart openings in the paddle wheel modulate the ultrasonic signal to produce an output signal which is applied to detection and indicating circuitry. The depth of insertion of the housing and paddle wheel into the conduit is adjustable.

Abstract: A transceiver capable of transmitting and receiving ultrasonic signals for liquid level gauging, the elapsed time between the transmission of a pulse and the reception of an echo pulse reflected from the surface of the liquid being measured to afford an index of the level of the liquid. The transponder is constituted by a piezoelectric transducer assembly suspended within an open-ended casing by an electrically non-conductive elastomeric material which serves to rapidly damp the vibratory activity of the transducer to prevent ringing thereof which interferes with reception. In the assembly, the piezoelectric transducer is sandwiched between a loading plate and a horn-shaped radiating plate, the assembly being held together by a bolt which extends between the plates and passes through the transducer. The transducer operates in the compression mode and is therefore capable of operating reliably with a high voltage drive signal to cause the radiating plate to emit an ultrasonic beam having a narrow angle.