| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure an ultrasonic wave propagating time in the case of measuring the wave propagating time without influence of a delay time by providing a pair of ultrasonic vibrators opposed at a different distance from a pair of ultrasonic vibrators provided along a flow in addition to the latter ultrasonic vibrators. SOLUTION: An apparatus for measuring a flowing velocity of an ultrasonic wave used for a gas or the like comprises, in an ultrasonic wave flow rate measuring tube 1, for example, a main measuring unit 1a along a flowing direction of a fluid, and an auxiliary measuring unit 1b perpendicular to the unit 1a. In the unit 1a, a pair of ultrasonic vibrators 2, 3 are disposed at a distance L, and in the unit 1b, auxiliary ultrasonic vibrators 12, 13 are disposed, for example, at an L/2. Thus, propagating times of the waves from an upstream side to a downstream side and vice versa of the unit 1a and propagating times of the one to the other and vice versa of the unit 1b are measured. The respective times are processed by a predetermined formula to obtain the flowing speed of the wave. In the formula, a time delay generated in the case of measuring the propagating time is cancelled by a subtraction. |
