deltawaveC-P
User manual
systec Controls Mess- und Regeltechnik GmbH 8/139
www.systec-controls.de
3.
Measuring Principle
Picture 1 Measuring Principle
deltawaveC-P employs the precise ultrasonic transit-time differential
method. This method involves installation of two ultrasonic transducers on
the surface of the piping and their interconnection with the electronic
evaluation system. The ultrasonic transducers operate in alternating mode
as transmitter and receiver with cyclic exchange of ultrasonic signals.
Measurements cover the transit times of the upstream and downstream
signals (t1, t2). The electronic circuit of deltawaveC-P measures the
transit-time differential of the ultrasonic signals t1 and t2 that that travel
upstream and downstream. These signals are accelerated (t1) or retarded
(t2). The difference that develops between both signal transit times is
proportional to flow velocity and is used on combination with the piping
geometry data for precise calculation of the volumetric flow rate
calculation of flow velocity [m/s] calculation of flow rate [m3/s]
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