Flowlink 5.1 Software Instruction Manual - Isco

Isco Flowlink 5.1 ® Software
Graph Window
best fit curve data point is offset by this offset value to
calculate the upper and lower limits.
Manning
Coefficients
Flow Profiles (Pulse
Doppler only)
Saving Graphs and
Tables
When adding a best fit curve using a Manning formula, Flowlink
opens a dialog box so you can add the Manning coefficients.
Enter values for the following:
• Diameter - Enter the pipe diameter.
• Slope - Enter the slope as a dimensionless quantity,
delta Y/ delta X, not as percent slope.
• Roughness - Enter the roughness coefficient for the pipe
(see page 86).
When graphing flow data from Pulse Doppler instruments, there
are five additional options for viewing the data. From either the
toolbar or Graphs>Flow Profile, you may select any combination
of the following views:
The Profile Cross-Section window shows a hydrograph and a
color contour plot of the flow profile. This flow profile is
developed from the raw beam velocity profiling information. This
raw velocity data is entered into an algorithm that produces a
mathematical description of velocity as a function of position
within the pipe or channel. The Y axis represents channel height,
and the X axis represents channel width. Velocity is represented
by different colors.
Velocity and Velocity Vector plots indicate the quality of the
sensor installation and alignment. In a perfect installation,
Beams 1 & 3 will be equal in amplitude and opposite in sign.
Beams 2 & 4 will also be equal in amplitude and opposite in sign,
but will have a greater amplitude than 1 & 3 by approximately
50%. Even in a perfect installation, however, hydraulic
conditions may still produce asymmetrical beam profiles.
A Pulse Doppler instrument operates by emitting a sound pulse
and then receiving the echoes backscattered by material
suspended in the flow. Amplitude is a measure of the strength of
this return signal.
Correlation is a measure of the quality of the processed velocity
information. Lower Correlation values (e.g., below 100) are an
indication of poor quality velocity data. Higher Correlation
values (e.g., above 150) may indicate external interference (noise)
or the presence of a “hard” acoustic barrier.
The Play/Pause Graph button on the toolbar shows the data
sequence in a continuous loop until Play/Pause Graph is pressed
again.
Once you have created a graph or a table, you can save it for later
use, or to be used as an object in another application. Flowlink
supports Object Linking and Embedding (OLE 2.1).
To save a graph or table:
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