Time Scanning of Airborne Reflected Fundamental and Second Harmonic Ultrasonic Pulse Amplitudes
Sittisak Siriwitayakorn* and Kingkeo Siriwitayakorn* Author for corresponding; e-mail address: cmjs@cmu.ac.th
Volume: Vol.30 No.1 (APRIL 2003)
Research Article
DOI:
Received: 28 November 2002, Revised: -, Accepted: 24 January 2003, Published: -
Citation: Siriwitayakorn S. and Siriwitayakorn K., Time Scanning of Airborne Reflected Fundamental and Second Harmonic Ultrasonic Pulse Amplitudes, Chiang Mai Journal of Science, 2003; 30(1): 19-25.
Abstract
Ultrasonic waves at 44.7 KHz were used to investigate the effect of reflector's shape and area on the reflected fundamental and second harmonic pulse amplitudes. The work was carried out in the normal air medium. The technique of varying the time of flight of ultrasonic pulses along with the improved measuring system revealed reproducible patterns of the reflected fundamental and second harmonic pulse amplitudes of a particular reflector shape. Results of various reflector shapes were compared.