ULTRASONIC FLOW VELOCITY DISTRIBUTION METER AND FLOW METER, ULTRASONIC FLOW VELOCITY DISTRIBUTION AND FLOW RATE MEASURING METHOD, AND ULTRASONIC FLOW VELOCITY DISTRIBUTION AND FLOW RATE MEASURING PROCESSING PROGRAM

摘要

PROBLEM TO BE SOLVED: To measure a flow velocity distribution or flow rate along a measuring line with high accuracy and high reliability by improving the reliability of the correlation between ultrasonic echo signals from an ultrasonic reflector. SOLUTION: This ultrasonic flow velocity distribution meter and flow meter comprises an emission trigger oscillation means 22; an ultrasonic oscillation means 23; an ultrasonic pulse receiving means 24; a signal processing means 25 processing received ultrasonic echo signals; and a signal analysis means 26 analyzing the ultrasonic echo signals to calculate the position and speed of the ultrasonic reflector along the measuring line, and measuring the flow velocity distribution or flow rate of a fluid. The signal processing means includes a filtering processing part 31 extracting the same frequency band as an ultrasonic pulse used for measurement from the received ultrasonic echo signals, and an AD converter 32 digitizing the extracted ultrasonic echo signal. The signal analysis means calculates the correlation of reference wave and search wave which are reflected waves from two ultrasonic pulses obtained at a predetermined time interval by use of a fluctuating search window method using a search window the size of which is set for every trigger oscillating periodτ. COPYRIGHT: (C)2005,JPO&NCIPI