Method for electromagnetic ultrasonic conversion for monitoring the fill level and bubble formation in enclosures containing liquid

US4934191A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Michael Kroening · Riegelsberg, DE
• Ernst Loehr · Alzenau, DE
• Albin Walleser · Offenbach, DE
• Gerhard Huebschen · Saarlouis, DE
• Wilhelm Repplinger · Schömberg, DE
• Hans-Juergen Salzburger · Neunkirchen, DE

Key dates

• Filing date: Sep 26, 1988
• Grant date: Jun 19, 1990
• Expiry date: Sep 26, 2008

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E30/30
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for electromagnetic ultrasonic conversion includes exerting dynamic-mechanical forces upon particles of an electrically conductive material of a test sample by superimposing quasi-static magnetic and electromagnetic high-frequency fields of a transmission converter for generating ultrasonic vibrations when transmitting. Electrical fields are induced by waves arriving in the test sample resulting in vibrations of the particles of material inductively affecting the fields of a receiver converter when receiving. The excitation of the vibrations when transmitting and the induction of electrical fields when receiving are effected by Lorentz and magnetic forces as well as by magnetostriction forces if the test sample is ferromagnetic. Fill level and bubble formation are monitored in enclosures in the form of containers and pipelines for liquid, by coupling a transmission converter and a receiver converter to an enclosure wall. Ultrasonic vibrations are generated in the wall inducing echo signals differing by amplitude and/or phase in the receiver converter, depending on whether the interior of the enclosure contains liquid, liquid containing steam or gas bubbles, or only a fluid…