2-1
Pressure definition
2-2a
Orifice flow
2-2b Contraction at an orifice
2-3a
Energy balance in pipe flow
2-3b Energy balance in open channel flow
2-3c Specific energy balance
2-4
Definitions of hydraulic radius
and hydraulic mean depth
2-5
Venturi meter
2-6 Pipe
orifice meter
2-7
Typical calibration curve for an
8-in venturi meter
3-1
Histogram of discharge coefficients
3-2
Percent full-scale deviation of
flow rate versus actual (comparison standard) flow rate
3-3
Comparison of actual (comparison
standard) and full-scale accuracy
3-4
Percent registration form of calibration
5-1
Example of poor approach flow conditions
upstream from weir
5-2 Weir
proportions
5-3
Underpass wave suppressor
5-4
Turbulence and waves in a Parshall
flume produced by an outlet works stilling basin
5-5
Underpass-type wave suppressor reduces
turbulence and waves in Parshall flumes
5-6 Weir
approach flow
5-7
Sediment deposits in weir pool
5-8
Poorly maintained weir edge
5-9
Examples of piezometer installation
5-10
Examples of piezometer manifold
tubing
5-11
Manometry system below the hydraulic
grade line is desirable
5-12
Manometry system above the hydraulic
grade line is undesirable
5-13
Cipoletti weir operating with good
flow conditions in the approach pool
6-1
Chain gage
6-2
Nonrecording wire and weight-type
gage
6-3
Horizontal drum water-stage recorder
6-4
Continuous recording water-stage
recorder with cover raised
6-5
Typical installation of a continuous
water-stage recorder in a wooden shelter
6-6
Digital recorder
6-7
Digital recorder punched tape
6-8
Programmable battery operated recording
unit
6-9
Stilling well and recorder house
made of wood
6-10
Plans for reinforced concrete recorder
house and stilling well
6-11
Current-meter gaging station with
cable car, corrugated steel shelter house, and stilling well
6-12
Plans for smooth and corrugated
steel pipe recorder housing and stilling wells
7-1
Different kinds of sharp-crested
weirs
7-2
Cipolletti weir operating with full
contractions at the end and on the crest
7-3
Suppressed rectangular weir at a
canal drop
7-4
Value of width-adjustment factor
from Georgia Institute of Technology tests
7-5
Effective coefficient of discharge,
Ce, as a function of L/B and h1/p,
from Georgia Institute of Technology tests
7-6a
Head correction factor, kh,
for V-notches of any angle
7-6b Effective coefficient, Ce, for fully contracted
V-notches of any angle
7-7
Effective coefficient, Ce,
for partially contracted 90-degree V-notches
7-8
Section through suppressed weir
with air vent in wall
7-9
Cipolletti weir with a well-type
head-measuring station
7-10
Compound weir with 90-degree notch
and suppressed rectangular crest used by U.S. Forest Service
7-11
Weir box turnout with Cipolletti
weir
7-12
Standard designs for 5.0-ft3/s
weir box turnout
7-13
Baffle arrangement and rating table
for 12-ft3/s weir box turnout
7-14
Adjustable Cipolletti weir in a
division box
7-15
Sectional view of an overshot gate
7-16
Correction factor, Ca,
versus gate leaf angle, 
,
for use in equation 7-9
7-17
Discharge equation for short-crested
triangular weir
8-1
Large long-throated flume for left
to right flow in Arizona canal
8-2
Four-foot, short-form Parshall flume,
discharging 62 ft3/s under free-flow conditions
8-3 Some
typical flumes
8-4
Typical staff gage for measuring
head or water stage
8-5
Flat-crested, long-throated flume
in concrete-lined canal
8-6 Flow
measurement structure for earthen
channel with a rectangular control section
8-7
Long-throated flume in a partially
filled circular conduit
8-8
Layout scheme for portable long-throated
measurement structures in partially full circular conduits
8-9
Parshall flume dimensions
8-10
Rate of submerged flow through
a 1-in Parshall flume
8-11
Rate of submerged flow through
a 2-in Parshall flume
8-12
Rate of submerged flow through
a 3-in Parshall flume
8-13
Relationship of hc
and hb gages for 1-, 2-, and 3-in Parshall flumes for
submergence greater than 50 percent
8-14
Diagram of determining rate of
submerged flow for a 6-in Parshall flume
8-15
Diagram for determining rate of
submerged flow for a 9-in Parshall flume
8-16
Diagram for determining correction
to be subtracted from free discharge to obtain rate of submerged flow
for
1- through 8-ft Parshall flumes
8-17
Diagram for determining correction
to be subtracted from free discharge flow to obtain submerged flow
discharges
through 10- to 50-ft Parshall flumes
8-18
Head loss through 10- to 50-ft
Parshall flumes
8-19
Head loss through 1- to 8-ft Parshall
flumes
9-1
Submerged-orifice measurement structure
viewed from upstream
9-2
Schematic diagram of a CHO turnout
9-3 A
single-barrel CHO turnout
9-4
Schematic view of a single-barrel
CHO turnout with a horizontal inlet channel
9-5
Schematic view of a CHO turnout
with a sloping inlet channel and with piezometers and stilling wells
9-6
Baffles to reduce water surface
fluctuations at staff gages in CHO turnouts
9-7
Gated orifice check structure used
to maintain upstream water surface levels and to measure rates of flow
in the Courtland Canal, Nebraska
9-8
Diagram of radial gate showing calibration
variables
9-9
Typical meter gate installation
9-10
Coefficient of discharge curve
for meter gates with downstream pressure tap at D/3.
10-1
Current-meter station on a canal,
viewed from upstream
10-2
Equipment for making wading measurements
with a current meter
10-3
Current-meter gaging station with
cable car, corrugated steel shelter house, and stilling well
10-4
Type A crane and current-meter
assembly in position on bridge
10-5
Making a current-meter measurement
from a boat
10-6
Cableway with traveling block to
support the current meter and position it for readings
10-7
Carriage and track for handling
current meter and weights from a bridge
10-8
Typical current-meter rating table
10-9
General assembly of Price type
AA current meter
10-10
Assembly drawing of Price type
AA current meter
10-11
Assembly drawing of Price type
BTA current meter
10-12
Assembly drawing of pygmy-type
current meter
10-13
Price type AA current meter on
a round wading rod
10-14a
"Dumas" current meter
of the propeller type with horizontal axle
10-14b Truck-mounted assembly of eight propeller-type current meters
and
signal recording equipment used on Gateway Canal, Weber Basin Project,
Utah
10-15
Top setting wading rod
10-16a
Calculation of discharge using
the midsection method
10-16b Calculation of discharge using Simpson=s parabolic rule method
10-17
Typical current-meter notes and
computations for the midsection method using equation 10-5
10-18
Typical discharge, mean velocity,
and area curves for a canal
11-1
Transit-time acoustic flowmeters
11-2 Doppler-type acoustic flowmeter
and cross-correlation acoustic flowmeter
12-1
General arrangement of salt-velocity
equipment for pressure conduits
12-2
Brine injection equipment in conduit
12-3
Sample records of a salt cloud
passing upstream and downstream electrodes in the salt-velocity method
of measuring flows in pipelines
14-1
Typical calibration curve for an
8-in venturi meter - one kind of differential flowmeter
14-2
Sectional view of venturi meter
14-3
Sectional view of nozzle meter
14-4
Sectional view of orifice meter
14-5
Flange and D-D/2 pressure
taps for orifice meter
14-6
Typical propeller meter installation
14-7
Velocity distributions in a pipeline
14-8
Schematic view of a magnetic flowmeter
14-9
Pitot tubes and manometer
14-10
Locations for pitot tube measurements
in circular and rectangular conduits
14-11
Typical arrangement for measuring
flow by the California pipe method
14-12
Discharge curves for measurement
of flow from vertical standard pipes
14-13
Purdue method of measuring flow
from a horizontal pipe
14-14
Flow from horizontal standard
pipes by Purdue coordinate method
14-15
Discharge through ditch-to-furrow
pipes and siphons (figures 14-16 and 14-17) may be determined by
measuring
the effective head
14-16
Rates of flow through ditch-to-furrow
pipes for various heads
14-17
Rates of flow through ditch-to-furrow
siphons for various heads
14-18
Discharge of aluminum or plastic
siphon tubes at various heads for different tube lengths