Acoustic Flowmeter

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

This type of flowmeter (ultrasonic) can give a continuous measurement of the flow rates of both open channel or pipe. It is nonintrusive, nonmechanical and can give a reading in either flow direction.

There are two types used:

  • Ultrasonic Doppler Meter
  • Ultrasonic Transit-time Meter


Acoustic Flowmeter FORMULA

\(\large{ v_a = \frac {l} {2 \; \cos \; \theta} \left( \frac {1} {t_d} - \frac {1} {t_u} \right) }\) 
Symbol English Metric
\(\large{ v_a }\) = average axial velocity of water flow \(\large{ \frac{ft}{sec} }\) \(\large{ \frac{m}{s} }\)
\(\large{ l }\) = acoustic path length between transducer faces \(\large{ ft }\) \(\large{ m }\)
\(\large{ t_d }\) = acoustic signal downstream travel time \(\large{ sec }\) \(\large{ s }\)
\(\large{ t_u }\) = acoustic signal upstream travel time \(\large{ sec }\) \(\large{ s }\)
\(\large{ \theta }\) = angle between acoustic path and the pipe's longitudinal axis \(\large{ deg }\)  \(\large{ rad }\)


Acoustic Flowmeter calculator


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Tags: Flow Equations Open Channel Equations Calculators