Ultrasonic flow meter ( average velocity )

Description

An ultrasonic flow meter is a type of flow meter that measures the velocity of a fluid with ultrasound to calculate volume flow. Ultrasonic flow meters are affected by the acoustic properties of the fluid Using ultrasonic transducers, the flow meter can measure the average velocity along the path of an emitted beam of ultrasound, by averaging the difference in measured transit time between the pulses of ultrasound propagating into and against the direction of the flow or by measuring the frequency shift from the Doppler effect. By using the absolute transit times both the averaged fluid velocity and the speed of sound can be calculated.

Related formulas

Variables

vThe average velocity of the fluid along the sound path (m/s)
LThe distance between receiving and transmitting transducers (m)
αThe inclination angle (degrees)
tupThe transit time of ultrasonic pulses propagating against flow direction (s)
tdownThe transit time of ultrasonic pulses propagating into the direction of the flow (s)