4220 Flow Meter
Section 2 Programming
2-32
If you select ROUND PIPE for the Manning flow conversion, the
following displays will appear:
Slope is entered as a dimensionless quantity, delta Y/ delta X, not
as percent slope. Or, as otherwise expressed:
Roughness coefficients are published in the Isco Open Channel
Flow Measurement Handbook. You must know the material the
pipe is made of. The roughness coefficients are published for all
common materials in three grades: minimum, normal and
maximum. Then:
If you select U-CHANNEL for the Manning flow conversion, the
following displays will appear:
(
Slope and roughness are entered as for ROUND PIPE previ-
ously.) Then:
If you select RECTANGULAR for the Manning flow conversion,
the following displays will appear:
(Slope and roughness are entered the same as for ROUND PIPE
previously.) Then:
MANNING ROUND PIPE
SLOPE = X.XXXXX ROUGH = X.XXXX
MANNING ROUND PIPE
DIAMETER = X.XXX FEET (or meters)
MANNING U-CHANNEL
SLOPE = X.XXXXX ROUGH = X.XXX
MANNING U-CHANNEL
WIDTH = X.XXX FEET (or meters)
MANNING RECTANGULAR
SLOPE=X.XXXXX ROUGH=X.XXX
MANNING RECTANGULAR
WIDTH=X.XXX FEET (or meters)
ΔX
ΔY
1
100
Rise
Run
= .01
=
For
example: