ULTRASONIC FLOWMETER, FLOW RATE MEASUREMENT METHOD, AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To reduce a computational effort increasing, when speed of flow is high or the bore of a pipe is large, and to reduce misrecognition of reflected echoes. SOLUTION: An ultrasonic flowmeter includes an ultrasonic oscillating means (15) for generating ultrasonic pulses in a constant cycle and outputting it into a fluid to be measured; a continuous pulse oscillating means (15a) for oscillating continuous waves of the same frequency as that of the pulses; an ultrasonic wave receiving means (15) for receiving an ultrasonic echo signal from the fluid; a multiplying means (30a) for multiplying the received ultrasonic echo signal with the continuous waves; a signal analysis means for analyzing the processed signal for calculating position and the speed of an ultrasonic reflector along a measurement line; and an output means (40) for outputting at least one of a flow speed distribution and the flow rate of the fluid from the position and the speed of the ultrasonic reflector calculated by the analysis means. The signal analysis means analog-digitally converts a composited waveform signal, obtained by the multiplying means (30a) and carries out signal analysis by means of a low-pass filter. COPYRIGHT: (C)2009,JPO&INPIT