Patent ID: 6708570
Filing Date: 2004-03-23
Classification: G01F

Abstract:
A flow rate measurement method, which measures a flow rate of a fluid flowing through a conduit, comprising:preparing a reference ultrasonic velocity such that the fluid is in a standard condition; measuring an ultrasonic velocity A by transmitting an ultrasonic wave from one side and receiving the ultrasonic wave at the other side in the fluid flowing through the conduit; measuring an ultrasonic velocity B by transmitting an ultrasonic wave from the other side and receiving the ultrasonic wave at the one side in the fluid flowing through the conduit; averaging the ultrasonic velocity A and the ultrasonic velocity B thereby to obtain an absolute ultrasonic velocity in the fluid; dividing a difference between the ultrasonic velocity A and the ultrasonic velocity B by 2 thereby to obtain a temporary flow velocity of the fluid; correcting the temporary flow velocity by using a difference between the reference ultrasonic velocity and the absolute ultrasonic velocity thereby to determine an accurate flow velocity of the fluid; and determining a flow rate of the fluid by using the accurate flow velocity and a cross section area of the conduit.