Ultrasonic flow-rate measurement device and ultrasonic flow-rate measurement method

Abstract

An ultrasonic flow-rate measurement device and an ultrasonic flow-rate measurement method capable of accurately measuring a flow rate of a fluid to be measured with a simple configuration are obtained. A reference-sound-pressure distribution waveform holding unit () holds a reference sound pressure distribution waveform based on an ultrasonic pulse emitted from a transmitter () and incident on at least three receivers () in a state where a flow velocity of a fluid (G) to be measured in the pipe () is zero. A variable-sound-pressure distribution waveform acquisition unit () acquires a variable sound pressure distribution waveform based on the ultrasonic pulse emitted from the transmitter () and incident on the at least three receivers () in a state where the flow velocity of the fluid (G) to be measured in the pipe () is not zero. A flow-rate calculation unit () obtains a shift amount (S), which is a difference between the reference sound pressure distribution waveform and the variable sound pressure distribution waveform, and integrates the shift amount (S), thereby calculating a flow rate of the fluid (G) to be measured in the pipe ().