| 摘要 |
PROBLEM TO BE SOLVED: To enable accurate measurement of flow velocity and flow rate considering the influence of temperature change. SOLUTION: In the clamp-on type Doppler ultrasonic flow velocity distribution meter transmitting ultrasonic wave to a fluid in a pipe from an ultrasonic transmitting and receiving means set on the outer wall surface of the pipe and measuring the flow velocity distribution of the fluid based on the Doppler frequency of the ultrasonic echo reflected by a reflector within the fluid, a wedge 14 for inclining an ultrasonic oscillator 13 at a predetermined angle to transfer the ultrasonic wave to the fluid is interposed between the ultrasonic oscillator 13 of the ultrasonic transmitting and receiving means and the outer wall of the pipe. The temperature of the wedge 14 is measured by a temperature sensor 15, and the sound velocity of the wedge is derived from the measurement result. The sound velocity of the wedge, the Doppler frequency, the ultrasonic inclination within the wedge, and the transmitting frequency of the ultrasonic transmitting and receiving means are assigned to a specified expression to calculate the flow velocity of the fluid. COPYRIGHT: (C)2005,JPO&NCIPI |
