ULTRASONIC VORTEX FLOWMETER

PROBLEM TO BE SOLVED: To provide an ultrasonic vortex flowmeter capable of utilizing two sets of ultrasonic sensors and preventing interference between ultrasonic waves. SOLUTION: A shield plate 20 is disposed in the hollow part 8 of a vortex generator main body 6. Since two ultrasonic wave propagation paths 19 are separated from each other by the shield plate 20, interference between ultrasonic waves transmitted from first and second transmitters 18a, 18b can be inhibited. For a shield plate passage 21, first and second communication ports 13, 14 are arranged at the lower end of a vortex generator 5. Therefore, since gas to be measured flows in opposite directions in the two ultrasonic wave propagation paths 19 separated by the shield plate 20, a receiving phase comparator 25 calculates a difference between two received ultrasonic signals and thereby obtains a value which is twice an original value as the amount of modulation caused by changes in gas flow, so that measuring efficiency can be enhanced. Simultaneously, the influence of changes in acoustic velocity with which both received ultrasonic signals are afflicted is canceled out whereby accurate flow measurements can be made.