Abstract
This paper describes a fundamental study for UVP measurement of boiling two-phase flow. The ultrasonic sensor for transmitting and receiving ultrasonic pulse decreases the sensitivity with temperature rise, because the piezoelectric elements of the sensor loses the piezoelectric effect over Curie temperature. So the high-temperature ultrasonic sensor is required for boiling two-phase flow measurement. In this study, the ultrasonic sensor with allowable temperature limit of 120 degrees Celsius was produced by using the 1-3 composite oscillator, which has high sensitivity and has been used widely for fluid flow measurement. Using this ultrasonic sensor, the rising velocity profiles of vapor bubbles generated by a heater were measured by UVP monitor.
