DOPPLER ULTRASONIC FLOWMETER

摘要

A Doppler ultrasonic flowmeter comprises ultrasonic transmitting means for emitting an ultrasonic pulse into a fluid pipe from an ultrasonic transducer, flow velocity distribution measuring means for measuring the flow velocity distribution of the fluid being measured by receiving ultrasonic echos reflected from the measurement region in the fluid pipe, fluid flow rate calculating means for calculating the flow rate from the flow velocity distribution of the fluid, and frequency selection setting means for automatically selecting a fundamental frequency of an ultrasonic wave causing a resonance transmission phenomenon from the ultrasonic transducer. The frequency selection setting means controls the operation of the ultrasonic transmitting means so that an ultrasonic wave of the selected most suitable frequency may be generated by the ultrasonic transducer. With this constitution, a Doppler ultrasonic flowmeter with high uersatility for simply and readily measuring the flow rate of a fluid being measured and flowing in a fluid pipe of any of various types in a noncontact way with good accuracy and precision.