Nivus NFP, Инструкция по эксплуатации

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Functional Principle
NFP - rev. 04 / 23.05.2018 page 21
Fig. 18-3 Echo signal images and evaluation
Based on the beam angle, the interval between both transmitted signals and the lag of the
signal pattern therefore in each single measurement window the flow velocity can be deter-
mined.
Stringing together the single flow mathematically velocities results in the flow profile of the
acoustic path which is directly indicated on the display of NFP.
Fig. 18-4 Investigated flow profile
If there are appropriate banking distances on the measurement place available, based on the
known pipe geometry and the velocity distribution a 3-dimensional flow distribution can be
rendered.
From this flow velocity distribution and the mathematical weighting of the individual gates re-
garding the Reynolds number it is possible to calculate the average flow velocity. From this
velocity multiplied by the circular pipe area we can obtain the flow rate. This rate can either
be a free programmable analog signal or an impulse signal as well.