DOPPLER TYPE ULTRASONIC FLOW METER, FLOW METERING METHOD, AND COMPUTER PROGRAM

摘要

Provided is a technique for performing a precise flow rate measurement of a large-bore pipeline without causing any aliasing. Ultrasonic pulses are transmitted at a first repetition frequency and at a second repetition frequency different from the first one, and fluid velocity distribution measuring means measures a first flow velocity distribution for the first repetition frequency and a second flow velocity distribution for the second repetition frequency. Flow rate calculating means specifies either a first noise-superposed area to occur with the first repetition frequency or a second noise-superposed area to occur with the second repetition frequency, and calculates the flow velocity distribution either by eliminating the first noise-superposed area from the first flow velocity distribution and interpolating it with the second flow velocity distribution or by eliminating the second noise-superposed area from the second flow velocity distribution and interpolating it with the first flow velocity distribution.