ASTM D5390-93(2013)

Standard Test Method for Open-Channel Flow Measurement of Water with Palmer-Bowlus Flumes

SIGNIFICANCE AND USE
5.1 Although Palmer-Bowlus flumes can be used in many types of open channels, they are particularly adaptable for permanent or temporary installation in circular sewers. Commercial flumes are available for use in sewers from 4 in. to 6 ft (0.1 to 1.8 m) in diameter.  
5.2 A properly designed and operated Palmer-Bowlus is capable of providing accurate flow measurements while introducing a relatively small head loss and exhibiting good sediment and debris-passing characteristics.
SCOPE
1.1 This test method covers measurement of the volumetric flowrate of water and wastewater in sewers and other open channels with Palmer-Bowlus flumes.  
1.2 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Dec-2012
• ICS: 17.120.20 - Flow in open channels
• Technical Committee: D19 - Water
• Drafting Committee: D19.07 - Sediments, Geomorphology, and Open-Channel Flow

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D5390 − 93 (Reapproved 2013)
Standard Test Method for
Open-Channel Flow Measurement of Water with Palmer-
Bowlus Flumes
This standard is issued under the fixed designation D5390; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2.3 ASME Standard:
Fluid Meters Their Theory and Application
1.1 This test method covers measurement of the volumetric
flowrate of water and wastewater in sewers and other open
3. Terminology
channels with Palmer-Bowlus flumes.
3.1 Definitions—For definitions of terms used in this test
1.2 The values stated in inch-pound units are to be regarded
method refer to Terminology D1129.
as the standard. The SI units given in parentheses are for
3.2 Definitions of Terms Specific to This Standard:
information only.
3.2.1 boundary layer displacement thickness—the boundary
1.3 This standard does not purport to address all of the
layer is a layer of fluid flow adjacent to a solid surface (in this
safety concerns, if any, associated with its use. It is the
case, the flume throat) in which, owing to viscous friction, the
responsibility of the user of this standard to establish appro-
velocity increases from zero at the stationary surface to an
priate safety and health practices and determine the applica-
essentially frictionless-flow value at the edge of the layer. The
bility of regulatory limitations prior to use.
displacementthicknessisadistancenormaltothesolidsurface
that the surface and flow streamlines can be considered to have
2. Referenced Documents
been displaced by virtue of the boundary-layer formation.
2.1 ASTM Standards:
3.2.2 critical flow—open channel flow in which the energy
D1129 Terminology Relating to Water
expressed in terms of depth plus velocity head, is a minimum
D1941 Test Method for Open Channel Flow Measurement
for a given flowrate and channel. The Froude number is unity
of Water with the Parshall Flume
at critical flow.
D2777 Practice for Determination of Precision and Bias of
3.2.3 Froude number—a dimensionless number expressing
Applicable Test Methods of Committee D19 on Water
the ratio of inertial to gravity forces in free-surface flow. It is
D3858 Test Method for Open-Channel Flow Measurement
equal to the average velocity divided by the square root of the
of Water by Velocity-Area Method
product of the average depth and the acceleration due to
D5242 Test Method for Open-Channel Flow Measurement
gravity.
of Water with Thin-Plate Weirs
3.2.4 head—the depth of flow referenced to the floor of the
2.2 ISO Standards:
throat measured at an appropriate location upstream of the
ISO 4359 Liquid Flow Measurement in Open Channels—
flume;thisdepthplusthevelocityheadisoftentermedthetotal
Rectangular, Trapezoidal and U-Shaped Flumes
head or total energy head.
ISO 555 Liquid Flow Measurements in Open Channels—
Dilution Methods for Measurement of Steady Flow—
3.2.5 hydraulic jump—an abrupt transition from supercriti-
Constant Rate Injection Method cal flow to subcritical or tranquil flow, accompanied by
considerable turbulence or gravity waves, or both.
3.2.6 long-throated flume—a flume in which the prismatic
This test method is under the jurisdiction of ASTM Committee D19 on Water
throat is long enough relative to the head for essentially critical
and is the direct responsibility of Subcommittee D19.07 on Sediments,
flow to develop on the crest.
Geomorphology, and Open-Channel Flow.
Current edition approved Jan. 1, 2013. Published January 2013. Originally
3.2.7 primary instrument—the device (in this case the
approved in 1993. Last previous edition approved in 2007 as D5390 – 93 (2007).
flume) that creates a hydrodynamic condition that can be
DOI: 10.1520/D5390-93R13.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or sensed by the secondary instrument.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Available from American Society of Mechanical Engineers (ASME), ASME
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St., International Headquarters, Three Park Ave., New York, NY 10016-5990, http://
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D5390 − 93 (2013)
3.2.8 Reynolds number—a dimensionless number express- 6.2 The flume becomes inoperative if downstream condi-
ing the ratio of inertial to viscous forces in a flow. In a flume tions cause submergence (see 7.3.2).
throat the pertinent Reynolds number is equal to the (critical)
7. Apparatus
throat velocity multiplied by the throat length and divided by
the kinematic viscosity of the water.
7.1 A Palmer-Bowlus flume measuring system consists of
the flume itself (the primary), with its immediate upstream and
3.2.9 scow float—an in-stream float for depth sensing,
downstream channels, and a depth or head measuring device
usually mounted on a hinged cantilever.
(thesecondary).Thesecondarydevicecanrangefromasimple
3.2.10 secondary instrument—in this case, a device that
scale or gage for manual readings to an instrument that
measures the depth of flow (referenced to the throat elevation)
continuously senses the head, converts it to a flowrate, and
at an appropriate location upstream of the flume. The second-
displays or transmits a readout or record of the instantaneous
ary instrument may also convert this measured head to an
flowrate or the totalized flow, or both.
indicated flowrate, or could totalize flowrate.
7.2 The Palmer-Bowlus Flume:
3.2.11 stilling well—a small free-surface reservoir con-
7.2.1 General Configuration:
nected through a restricted passage to the approach channel
7.2.1.1 ThePalmer-Bowlusflumeisaclassoflong-throated
upstreamoftheflumesothataheadmeasurementcanbemade
flume in which critical flow is developed in a throat that is
under quiescent conditions.
formed by constricted sidewalls or a bottom rise, or both.
3.2.12 subcritical flow—open channel flow that is deeper
Sloped ramps form gradual transitions between the throat and
and at lower velocity than critical flow for the same flowrate;
the upstream and downstream sections. See Fig. 1. The flume
sometimes called tranquil flow. 5
was developed primarily for use in sewers but it is adaptable
3.2.13 submergence—a condition where the depth of flow
to other open channels as well. There is no standardized shape
immediately downstream of the flume is large enough to affect
for Palmer-Bowlus flumes and, as long-throated flumes, they
theflowthroughtheflumesothattheflowratecannolongerbe
can be designed to fit specific hydraulic situations using the
related to a single upstream head.
theory outlined in 7.2.3.
7.2.1.2 Prefabricated Flumes—Prefabricated flumes with
3.2.14 supercritical flow—open channel flow that is shal-
trapezoidalorrectangularthroatsandwithcircularorU-shaped
lower and at higher velocity than critical flow for the same
outside forms are commercially available for use in sewers.
flowrate.
Although there is no fixed shape for Palmer-Bowlus flumes,
3.2.15 tailwater—the water elevation immediately down-
many manufacturers of trapezoidal-throated flumes use the
stream of the flume.
proportions shown in Fig. 2. These prefabricated flumes are
3.2.16 throat—the constricted portion of the flume.
also available in several configurations depending on how they
3.2.17 velocity head—the square of the average velocity
are to be installed, for example, whether they will be placed in
divided by twice the acceleration due to gravity. thechannelatthebaseofanexistingmanhole,insertedintothe
pipe immediately downstream of the manhole, or incorporated
4. Summary of Test Method into new construction.The size of these prefabricated flumes is
customarily referenced to the diameter of the receiving pipe
4.1 In Palmer-Bowlus flumes, critical free-surface flow is
rather than to the throat width. Refer to manufacturers’
developed in a prismatic throat so that the flowrate is a unique
literature for flume details.
function of a single measured upstream head for a given throat
7.2.1.3 Becausethedimensionsofprefabricatedflumesmay
shape and upstream channel geometry. This function can be
differdependinguponthemanufacturerortheconfiguration,or
obtained theoretically for ideal (frictionless) flows and adjust-
both, it is important that users check interior dimensions
ments for non-ideal conditions can be obtained experimentally
carefully before installation and insure that these dimensions
or estimated from fluid-mechanics considerations.
are not affected by the installation process.
7.2.1.4 A Palmer-Bowlus flume can be fabricated in a pipe
5. Significance and Use
by raising the invert (see Fig. X3.1). Floor slabs that can be
5.1 Although Palmer-Bowlus flumes can be used in many
grouted into existing sewers are commercially available, as are
types of open channels, they are particularly adaptable for
permanent or temporary installation in circular sewers. Com-
Palmer, H. K., and Bowlus, F. D., “Adaptation of Venturi Flumes to Flow
mercial flumes are available for use in sewers from 4 in. to 6
Measurements in Conduits,” Trans. ASCE, Vol 101, 1936, pp. 1195–1216.
ft (0.1 to 1.8 m) in diameter.
5.2 A properly designed and operated Palmer-Bowlus is
capable of providing accurate flow measurements while intro-
ducing a relatively small head loss and exhibiting good
sediment and debris-passing characteristics.
6. Interferences
6.1 Flumes are applicable only to open-channel flow and
FIG. 1 Generalized Palmer-Bowlus (Long-Throated) Flume in a
become inoperative under full-pipe flow conditions. Rectangular Channel
D5390 − 93 (2013)
C 5 ~B /B!~1 2 δ /h! 2 (2)
D e *
Here B is an effective throat width given by:
e
B 5 B 2 2δ @~m 11! 2 2 m# (3)
e *
wheremisthehorizontal-to-verticalslopeofthesidesofthe
throat (zero for rectangular throats). The displacement
thickness, δ , is a function of the throat Reynolds number and
*
surface roughness. However, a reasonable approximation that
FIG. 2 Palmer-Bowlus Flume (Typical) for Sewer
is adequate for many applications is:
δ 5 0.003 L (4)
*
prefabricated slab-pipe combinations for insertion into larger
whereListhelengthofthethroat.(Betterestimatesofδ can
*
pipes. Details may be obtained from the manufacturers’ litera-
be obtained from boundary-layer theory, as in ISO 4359.)
ture. Discharge equations for this throat shape are given in
7.2.3.3 Shape Coeffıcient, C (SeeAlso Appendix X2)—C is
Appendix X1. S S
given in Table 1 as a function of mH /B.H is the upstream
7.2.2 Head Measurement Location—The head, h, on the e e e
total effective head, which is (for essentially uniform upstream
flume is measured at a distance upstream of the throat-
velocity distribution):
approach ramp that is preferably equal to three times the
maximum head. When the maximum head is restricted to
H 5 h1V /2g 2 δ (5)
e u *
one-half the throat length, as is recommended in this test
where V is the average velocity at the position of head
u
method, an upstream distance equal to the maximum head will
measurement. For a rectangular throat, m + 0 and C is unity.
S
usually be adequate to avoid the drawdown curvature of the
7.2.3.4 Velocity-of-Approach Coeffıcient, C —This coeffi-
flow profile. V
cient allows the flowrate to be expressed conveniently in terms
7.2.3 Discharge Relations:
of the measured head, h, rather than the total head, H:
7.2.3.1 The volumetric flowrate, Q, through a Palmer-
3 3
Bowlus flume of bottom throat width, B, operating under a
C 5 @~H 2 δ !/~h 2 δ !#2 5 ~H /h !2 (6)
V * * e e
head, h, above the throat floor is:
C is given in Table 2 as a function of C B h /A , where A
V S e e u u
Q 5 2/3 2g/3 1/2C C C Bh 2 (1)
~ !~ !
D S V
is the cross-sectional area of the flow at the head measurement
station. See also Appendix X3.
where g is the acceleration due to gravity and C C and C
D S V
are, respectively, the discharge coefficient, throat shape 7.2.3.5 Limiting Conditions—The foregoing discharge
coefficient, and velocity-of-approach coefficient as defined in equationandcoefficientsarevalidforthefollowingconditions:
the following sections. The derivation of Eq 1 is outlined in (a) 0.1 ≤ h/L ≤ 0.5, with minimum h = 0.15 ft (0.05 m),
Appendix X2. (b) B ≤ 0.33 ft (0.1 m),
7.2.3.2 Discharge Coeffıcient, C —Thiscoefficientapproxi- (c) h<6ft(2m),
D
mates the effect of viscous friction on the theoretical discharge (d) The throat ramp slopes do not exceed one or three,
by allowing for the development of a boundary layer of (e) Throat floor is level,
displacement thickness δ along the bottom and sides of the (f) Trapezoidal throat section is high enough to contain the
*
throat: maximum flow, and
TABLE 1 Shape Coefficient,C
S
mH /B C mH /B mC mH /B C mH /B C
e e S e e S e e S e e S
0.010 1.007 0.40 1.276 1.80 2.288 3.80 3.766
0.015 1.010 0.45 1.311 1.90 2.360 3.90 3.840
0.020 1.013 0.50 1.346 2.00 2.433 4.00 3.914
0.025 1.017 0.55 1.381 2.10 2.507 4.10 3.988
0.030 1.020 0.60 1.417 2.20 2.582 4.20 4.062
0.040 1.028 0.65 1.453 2.30 2.657 4.30 4.136
0.050 1.035 0.70 1.490 2.40 2.731 4.40 4.210
0.060 1.041 0.75 1.527 2.50 2.805 4.50 4.284
0.070 1.048 0.80 1.564 2.60 2.879 4.60 4.358
0.080 1.054 0.85 1.600 2.70 2.953 4.70 4.432
0.090 1.060 0.90 1.636 2.80 3.027 4.80 4.505
0.10 1.066 0.95 1.670 2.90 3.101 4.90 4.579
0.12 1.080 1.00 1.705 3.00 3.175 5.00 4.653
0.14 1.093 1.10 1.779 3.10 3.249 5.50 5.03
0.16 1.106 1.20 1.852 3.20 3.323 6.00 5.40
0.18 1.119 1.30 1.925 3.30 3.397 7.00 6.15
0.20 1.133 1.40 1.997 3.40 3.471 8.00 6.89
0.25 1.169 1.50 2.069 3.50 3.545 9.00 7.63
0.30 1.204 1.60 2.142 3.60 3.618 10.0 8.37
0.35 1.240 1.70 2.215 3.70 3.692 . .
D5390 − 93 (2013)
¯
TABLE 2 Velocity-of-Approach Coefficient,C
where d is the average approach depth (area divided by
V
u
C C h /A C water surfaced width).
S e e u V
0.1 1.002 7.3.2 Downstream Conditions—Submergence:
0.2 1.009
7.3.2.1 Palmer-Bowlus flumes must be installed so as to
0.3 1.021
avoid submergence by the tailwater. There is insufficient data
0.4 1.039
0.5 1.064 on flow through submerged flumes to permit flowrate adjust-
0.6 1.098
ments for this condition to be made reliably.
0.7 1.146
7.3.2.2 Submergence will be avoided if the tailwater depth
0.8 1.218
0.9 1.340 (relative to the throat floor) does not exceed the critical depth
in the throat. Values of the critical depth are given in Table 3.
Thisisaconservativecrit
...