NATIONAL INSTITUTE OF STANDARDS &

TECHNOLOGY

Research Iriormation Center

Gaithersburg, MD 2C®99

NISTIR 88-3898

NBS’ Industry - Government

/ \ Consortium Research Program

\ ® Flowmeter Installation

Effects:

Summaty Report with Emphasis on

Research Period July - December 1987

G. E. Mattingly and T. T. Yeh

U.S. DEPARTMENT OF COMMERCE

National Institute of Standards and Technology

(Formerly National Bureau of Standards)

National Engineering Laboratory

Center for Chemical Engineering

Fluid Flow Group

Chemical Process Metrology Division

Gaithersburg, MD 20899

May 1988

Issued November 1988

NiSTIR 88-3898

NBS’ Industry - Government

Consortium Research Program

on Flowmeter Installation

Effects:

Summary Report with Emphasis on

Research Period July - December 1987

G. E. Mattingly and T. T. Yeh

U.S. DEPARTMENT OF COMMERCE

National Institute of Standards and Technology

(Formerly National Bureau of Standards)

National Engineering Laboratory

Center for Chemical Engineering

Fluid Flow Group

Chemical Process Metrology Division

Gaithersburg, MD 20899

May 1988

Issued November 1988

National Bureau of Standards became the

National Institute of Standards and Technology

on August 23, 1988, when the Omnibus Trade and

Competitiveness Act was signed. NIST retains

all NBS functions. Its new programs will encourage

improved use of technology by U.S. industry.

U.S. DEPARTMENT OF COMMERCE

C. William Verity, Secretary

NATIONAL INSTITUTE OF STANDARDS

AND TECHNOLOGY

Ernest Ambler, Director
PREFACE

The research results reported in this document were produced at the support of

an NBS initiated industry -government consortium. In this mode of operation,

there is a high degree of interaction between the representatives of the

consortium member companies and the NBS researchers. These interactions

include: (1) the planning of the specific focus of the NBS research efforts,

(2) the analyses of the results obtair d, and (3) the conclusions drawn for

the particular phase of the work. For this reason, it is pertinent to

acknowledge both the support given to this phase of the research program and

the technical contributions made by the representatives of the consortium

members

.

The current consortium members are alphabetically:

1. Ametek-McCrometer

2. Chevron Oil

3. Daniel Industries

4. Department of Energy

5. Dow Chemical Co.

6 ; E . I

.

Dupont de Nemours

7. Fischer & Porter

8. Ford Motor Co.

9. Gas Research Institute*

10. Gas Unie (The Netherlands)

11. Instrument Testing Service

12. ITT Barton

13. Kimmon Mfg. Ltd. (Japan)

14. NBS-B

15. Rockwell International

16. Rosemount

*Specific acknowledgment is due to Dr. Kiran Kothari of GRI . Both his support

for this program and his technical inputs in the analyses of results and in

the conclusions drawn are gratefully acknowledged.

ii
TABLE OF CONTENTS

Page

PREFACE ii

ABSTRACT 1

INTRODUCTION 1

EXPERIMENTAL RESULTS 2

CONCLUSIONS 9

REFERENCES 10

TABLE 11

FIGURES 12
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NBS* Industry - Government Consortium Research

Program on Flowmeter Installation Effects : Summary Report with Emphasis on Six Month Period

July - December, 1987.

G.E. Mattingly

T.T. Yeh

Fluid Flow Group

Chemical Process Metrology Division

Center for Chemical Engineering

National Bureau of Standards

Gaithersburg, Maryland 20899

ABSTRACT

This report presents results produced in a consortium- sponsored research

program on Flowmeter Installation Effects. This project is a collaborative

one that has been underway for three years; it is supported by an industrygovernment consortium that meets twice yearly to review and discuss results

and to plan subsequent phases of the work. This report contains the results

and conclusions of the recent meeting of this consortium at NBS-G on Feb. 17,

1988. At this meeting it was voted that results should be disseminated not in

meeting minutes format but rather in self-standing reports. Hence, we adopt

this format.

The objective of this research program is to produce improved flowmeter

performance when meters are installed in "non-ideal" conditions. This

objective is being attained via a strategy to (A) measure, understand, and

quantify the "non- ideal" pipe flows from such pipeline elements as elbows,

reducers, valves, or combinations of these, (B) for selected types of

flowmeters, correlate meter factor "shifts" relative to the features of these

"non- ideal" pipe flows so as to be able to accurately predict meter

performance in "non-ideal" installations, and (C) disseminate the resulting

technology through appropriate channels such as publishing our results in

pertinent journals and upgrading "paper" standards for flow measurement.

Specific results included in this report include:

1. the distributions of the mean and the turbulence velocities in the

axial and vertical directions in both the (closely coupled) elbows

out-of-plane piping configuration and the "spaced" version of this

arrangement

,

2. the pressure loss measurements for both of the elbow-out-of plane

configurations , and

3. the velocity distributions produced by the single elbow piping

configuration.

INTRODUCTION

The increasing scarcity of fluid resources and the rising value of fluid

products is placing new emphasis on improved fluid measurements. Improvement

is sought from many starting points. Meters are being retrofitted into fluid

systems that were not designed for them. This invariably means the flowmeters
are being installed in "non- ideal" conditions. Increased accuracy levels are

desired for installed metering systems - either by upgrading the flow

conditions that enter the meter or by replacing the device itself and/or its

auxiliary components.

The industry -government consortium (members are listed in Appendix 1) research

program currently underway at NBS is designed to help improve fluid metering

performance in these situations. The design of the program is to produce a

basic understanding of the flow phenomena that are produced in "non- ideal"

pipe flows and to quantify these phenomena. When these phenomena and their

quantified characteristics are correlated with the performance of specific

types of meters, it becomes feasible to predict and achieve - satisfactory

measurements in "non- ideal" meter installations.

Pipe flows from selected piping configurations are measured using laser

Doppler velocimetry (LDV) . Selections of piping configuration are done by

consortium members; one or two such configurations can be done in one year.

The LDV techniques that have been and are being applied to determine pipe

flows can also be used to measure the effects of other pipeline elements

valves, flow conditioning elements (for fluid velocity or pulsations, etc.),

mixing “^devices , generic flowmeter geometries - or combinations of these. The

resulting understanding provides the bases for improving the effectiveness of

these devices and, in turn, for increasing the productivity of the continuous

processes which depend upon them. [1-4]*

EXPERIMENTAL RESULTS:

In what follows, results are presented for a range of pipeline configurations

that have been investigated in this NBS industry government consortium

project: the elbows-out-of-plane configuration where the elbows are welded

together [1,2], the elbows-out-of-plane with a short (2.42) length of straight

pipe separating the elbows, and the single elbow.

1, Mean Velocity and Turbulence Measurements. The right hand coordinate

system used in what follows has an origin at the pipe centerline in the

exit flange plane of the elbows-out-of-plane configuration. The positive

Z direction is downstream; the positive Y direction is upward; the X

direction is therefore to the right looking upstream. The mean

velocities in the X, Y, and Z directions are U, V, and W, respectively;

the corresponding turbulence velocities, are u' ,v'

,

and w'

.

All

quantities are nondimensionalized using the bulk pipe flow velocity to

normalize all velocities and using the pipe inside diameter to normalize

lengths. For the elbows-out-of-plane configurations, the distributions

of the mean components of the streamwise i.e., W (Z direction) and the

vertical i.e., V (Y direction) components of the fluid velocities along

the horizontal diameter are plotted in Figure 1 (a) and (b) . These

piping configurations are referred to as the "welded" and "spaced"

* Square bracketed integers refer to references given below.

2
elbows-out-of-plane configurations. The legend "L + X - Y" in the figure

for the "welded" configuration: "L" refers to standard long-radius sweep

elbows, "+ X - Y" means that the entrance directions of the first and the

second elbows are in "+X" and "-Y" directions, respectively. In

addition, weld-neck flanges are welded onto both ends of each elbow

configuration, and the flow exiting from the elbow configuration is

always in +Z direction. This means that the pipe flow which enters the

configuration has a long length in the "+X" direction and the first elbow

turns the pipe flow into the "-Y" direction. The second elbow then turns

this pipe flow into the "+Z" direction. The "spaced" configuration is

denoted by "2.42Y" as this is the length of the spacer separating the

elbows. These graphs show the large deviations of the W profiles from

the power law distributions that pertain to an "ideal" meter installation

- i.e., very long lengths of straight, constant diameter piping

preceeding the meter position. The significant features of our measured

profiles are the "slow core" flows found near the centerline and. the

"high speed" regions nearer the pipe wall. Also significant is the

asymmetry noted for the most upstream station for the "welded" elbows and

the fact that the "spacer" alters the qualitative nature of the most

upstream profile.

Figures 2 (a) and (b) show the distributions measured for the V component

of the velocity that correspond to the results in figures 1 (a) and (b) . Again it is noted that the "spacer" produces qualitatively different

profiles at the most upstream station.

In figures 3 (a) and (b) are plotted the root-mean-square (r.m.s.)

distributions of the axial, turbulence components. Comparisons of these

results show that the spaced elbows values are reduced in level compared

to those of the welded configuration. This reduction is also noted to

apply to the r.m.s. profiles of the vertical, turbulent velocities shown

in figures 4 (a) and (b)

.

The mean components of streamwise, W, and vertical, V velocity

distributions are used to define the skew angle as the arctan (V/W) . Figure 5 shows the skew angle distribution for the "welded" elbows

configuration. Figure 6 shows corresponding values for the "spaced"

elbows configuration. It is noted again that the levels for the "spaced"

elbows configuration are reduced in comparison with the values for the

"welded" configuration.

2. Swirl Decay. When a Swirl number is defined as

r+.5 SI = 4 WVXlX|dX

•^-.5

and the axial distributions are calculated for the respective piping

configurations, the results can be shown as in figures 7 and 8. When

exponential decay formulas are fitted to these results the decay rates

obtained can be compared to the corresponding values determined by other

investigators. Table 1 contains such a comparison. [3-7] It is noted

from table 1 that the exponential decay rate is, according to these

3
values, a decreasing function of pipe diameter Reynolds number. Figure 9

presents these exponential decay rates versus diametral Reynolds number.

Pressure Measurements. Figure 10 presents a sketch of the piping

configurations and the locations of the pressure taps used to measure the

static pressure in these pipe flows. Dimensions are given in pipe

diameters; the cross-sectional sketch shows the azimuthal locations of

the four (4) taps positioned (looking upstream) at each streamwise

station. Figures 11 and 12 present differential static pressure

distributions (in numbers of velocity heads "Nvh") for the four (4)

angular locations both upstream (A) and downstream (B) of the respective

elbow-out-of-plane configuration. The reference pressure chosen for the

differences is that of tap No. 4, see figure 10. These figures contain

results for several diametral Reynolds numbers as noted in the legends.

Figure 13, shows the differential static pressure distributions both

azimuthally and at four stream stations (lettered as A, B, C, and D shown

in the legend) for both piping configurations. Pressure levels are shown

relative to the minimum pressure measured - i.e., the lowest value

measured at the station furthest downstream - in "Nvh". Results shown

are those for Re = 6 x 10^ . Comparison of pressure at the same stream

stations indicates that the differentials, P - Pmin are larger for the

welded elbows compared to the spaced elbows. A small, but noticeable

(~0.15 Nvh) azimuthal pressure variations appear at each station. Due to

the helical motion of the flow in the pipe, these pressure variations

vary from station to station. Therefore, in some conditions, careful

selection on the pressure tap positions should be taken.

Friction Factor Results. Figures 14-17 present the results for the

pressure measurements plotted in the format of friction factor:

f = Ap/(l/2pWb2L) = Nvh/L

In each of these figures, the letters A,B,C, and D denote streamwise

stations along the pipe. As shown in the sketch, A precedes the double

elbow configuration; B is the station at the configuration outlet; C and

D are stations downstream. In figures 14 and 15 are shown, via the

integers 1-4, the azimuthal pressure tap locations at each of the

lettered stations, looking upstream.

Figure 14 shows results for the welded elbows configuration. Over the

flow rate range

10^ < Re < 10^

it is noted that the friction factor is monotonically decreasing.

Pressure differences measured for the No. 4 taps are the largest of the

four between stations A and B which are separated by a distance of 7.13

along the pipe centerline. At station B, taps No. 1-3 indicate

approximately the same pressure. It is concluded that this azimuthal

distribution of pressure difference between stations A and B is due to

the asymmetric swirl (helical motion) produced by this elbow
configuration. Figure 14 also shows that between the downstream stations

C and D the differences between the No. 4 tap and the Nos. 1-3 taps

appear to have diminished along the pipeline interval B-C.

Figure 15 shows results for the spaced elbows that are analogous to those

of figure 14. With the possible exception of the lowest flow rate,

similar trends are noted for the No. 4 tap and the Nos. 1-3 taps between

stations A and B. Between station B and C - a distance of some 23.2 the

largest differential pressure is measured between the No. 3 taps and Nos.

1,2, and 4 give closely similar results.

Figures 16 and 17 present cross-sectionally averaged pressure differences

between the lettered stations versus flow rate in Reynolds number for the

welded and spaced configurations, respectively. The conclusions drawn

here are:

(1) that the swirled flows produced within the elbow configurations

produce the largest friction factors, and

(2) that the friction factor decreases with distance downstream of

the pipe length along which it is determined.

Figure 18 presents the pressure losses produced through the elbow

configurations - i.e., from stations A to B in terms of equivalent

lengths of straight pipe, in diameters. These results quantify the

pressure losses and show that for the spaced elbow configuration exceeds

that of the welded configuration. However, it is noted that the pressure

loss ratio closely approximates the length ratio for these

configurations. Thus, it does not appear that firm conclusions can be

drawn here regarding differences between the pressure losses per unit

length that might exist due to differences in the swirl characteristics.

5. Single Elbow Velocity Surveys. Figures 19 and 20 present, respectively,

the horizontal and vertical profiles of the mean vertical velocity

component at the 1.5 station downstream of the single elbow. The legend

and the sketch identify the data and the traversed diameter. As in the

previously investigated elbow configuration, this elbow is a standard,

long-radius sweep elbow with weld-neck flanges. It is noted from figure

19 that the secondary flow in this pipe flow consists of two counterrotating vortices symmetrically oriented with respect to the vertical

diameter. Figure 20 shows that the maximum negative (i.e., downward)

velocity component occurs about the 10% of the diameter point above the

centerline of the pipe.

It is concluded here that these flow characteristics are likely to be

present in the previous double elbow configurations where the pipe flows

exit the first of the two elbows. For the welded elbow configuration,

these distributions may not be developed completely before entering the

second elbow. For the spaced elbows these motions flow through the

straight pipe length that separates the two elbows before entering the

second elbow.

5
Figures 21 and 22 present, respectively, the horizontal and vertical

profiles, at Z = 1.5, of the mean component of the streamwise velocity.

Included also in these figures is the power law velocity distribution

(shown dashed) for the respective Reynolds number. Figure 21 shows the

symmetry of this profile about the vertical diameter through the pipe

centerline. It shows velocity over-shoots on either side of the pipe

flow with a slow center "core-flow". Figure 22 shows a high velocity

region near the bottom of the pipe and a slow "core-flow" over a large

central section of the pipe.

Figures 23 (a) and (b) and 24 (a) and (b) are analogous to figures 19 and

20, respectively, in that they show similar results for the three

streamwise stations devoted by Z = 1.5, 5.0, and 10.0; the respective

diametral Reynolds number of 10^ or 10^ are given in the legend of each

figure. It is noted from these results that there is rapid decay of

these secondary motions over these pipe lengths. This is surprising when

it is recalled that the swirl from the welded elbow configuration was

determined to persist at significant levels (i.e., swirl angle > 2°) 100

downstream! It is noted that the (dimensionless) velocity ordinates are

generally larger for the higher diametral Reynolds number flow than they

are for the lower. Of course, dimensionally the differences would be

much greater.

Figures 25 (a) and (b) and 26 (a) and (b) are analogous to figures 21 and

22, respectively, for the same stations. These confirm the unexpected

swirl decay effects noted above over the same pipeline distances. These

non-dimensional distributions show that some of the ordinates for the

lower Reynolds number cases exceed those for the higher Reynolds number

case. Of course, dimensionally the higher Reynolds values will exceed

those for the lower.

Figures 27 (a) and (b) and 28 (a) and (b) show respectively, the power

spectral distributions measured for the vertical and horizontal velocity

components on the pipe centerline for Re = 10^ and 10^ . These are loglog plots and they confirm that no ordered structures appear to be

present in these pipe flows.

Figures 29 (a) and (b) present measurement results for the root-meansquare (r.m.s.) of the vertical component of the turbulent velocity along

horizontal diameters at the streamwise stations, Z = 1.5, 5.0, and 10.0

for the two Reynolds numbers, as noted. Figure 30 presents Laufer's data

for Reynolds number = 5 x 10^. [7] This Laufer data, which is normalized

in the same manner as the current results, is found to have significantly

reduced levels. It is also noted that the distributions measured near

the exit of the single elbow deviate qualitatively from the Laufer

results, but these differences also diminish rapidly with downstream

distance

.

The vertical profile of the r.m.s. turbulent component in the vertical

direction is shown in figures 31 (a) and (b) for our two Reynolds

numbers, as noted. Again, it is apparent that a rapid decay of the broad

peak observed just below the pipe centerline at the Z = 1.5 station

6
occurs within the first ten diameters from this elbow. The Laufer data

corresponding closely to that shown in figure 31 (b) is shown in figure

32. This distribution indicates that the radial component of the

turbulence is less than 4% of the bulk averaged flow velocity at Laufer 's

Reynolds number of 5 x 10^ . As noted from figure 31 (b) at the

streamwise station denoted by Z = 10 the distribution shows our radial

turbulence component to be greater than 5% of the bulk velocity at all

locations along the vertical diameter.

The axial component of the turbulence velocity for our two Reynolds

numbers, for the same three stations near the exit plane of the single

elbow is shown in figures 33 (a) and (b) . At the most upstream of these,

the double -peaked distribution has maxima near 14% of the bulk average

velocity in the pipe for both Reynolds numbers. The qualitative nature

of this distribution changes differently with downstream distance for the

two Reynolds numbers. For Re = 10^ the double-peaked profile has

essentially disappeared at Z = 5. For Re = 10^ the double peaked profile

is preserved as shown in the profile at the Z = 5 station. However, by

the succeeding profile at Z = 10, the cross stream profile for the Re =

10^ flow has changed to resemble, qualitatively, the distribution

measured by Laufer. This is shown in figure 34, for a Reynolds number of

5 X 10^. That Laufer' s pipe flow results show this component of the

turbulence to be less that 8% of the bulk velocity everywhere along this

horizontal diameter corresponds to the comparisons made above.

Figures 35 (a) and (b) show the vertical profile of the axial r.m.s.

component of the turbulent velocity for the Reynolds numbers as noted.

The peaked distribution for Re = 10^ indicate a maximum of almost 16% at

the upstream station while that for Re = 10^ indicates a maximum level of

almost 14% of the bulk averaged velocity. These levels occur at

differing radial locations along the pipe diameter below the pipe

centerline. These peaked profiles are observed to decay rapidly with

downstream distance so that by the station Z = 10 turbulence levels are

essentially less than 10% of the bulk velocity everywhere along the

vertical diameter.

6. Skew Flux Distributions. The mean components of streamwise and vertical

velocity distributions can be combined to produce momentum flux

distributions. If the skew flux is defined as the product of axial and

vertical mean velocities WV, it can be considered as the axial flux of

the vertical momentum per unit density. The distribution of this

quantity across the horizontal diameter for Reynolds number 10^ is shown

in figure 36 for the three stations Z = 1.5, 5, and 10. These

distributions essentially mirror those shown in figure 23 but reduce the

minima on the centerline because of the "slow core" flow noted in the

axial distributions shown in figure 25. Maxima are shown in the skew

flux near the pipewall because of the axial velocity maxima occurring

there as shown in figure 25.

7
The vertical profile of the skew flux, WV is shown in figure 37 for

Reynolds number of 10^ . These profiles closely duplicate those of the

7. vertical profiles of vertical velocity shown in figure 24.

Skew Angle. Defining the skew angle as the arctan (V/W) , the horizontal

profiles for the skew angle are shown in figure 38 (a) and (b) for the

three stations near the elbow exit for two Reynolds numbers. These

indicate that skew angle levels fo-^ Reynolds number 10^ reach -14“ along

the pipe centerline. Subsequent profiles show that these extreme levels

of skew angle at the pipe centerline rapidly diminish to 3“ or less by

the Z = 10 station.

Figures 39 (a) and (b) show skew angle distributions along the vertical

diameter for the three stations for two Reynolds numbers, as noted. The

most upstream distribution shows that, for a skew angle of -16“ at about

10% of the pipe diameter above the pipe centerline. Again, rapid decay

of these skew angle distributions is noted with the Z = 10 station

showing that the skew angle is everywhere less than 2“.

8.

Swirl Intensity. If the sv;irl intensity is defined as the axial flux

(per unit density) of the moment of momentum about the pipe centerline,

the product is WVx. The cross-stream distribution for this product for

the single elbow for two Reynolds numbers for our same three stations is

shown in figure 40 (a) and (b) . The zero crossings at the centerline and

at two locations at approximately 20-25% diameter points on either side

of the centerline along a horizontal diameter show the presence of two

symmetric, counter-rotating vortices. It is not clear if the centers of

these vortices lie on this horizontal diameter, or above it - as perhaps

shown by figure 24 or 37. The decay of these two vortices is more rapid

than that observed earlier in the results for the elbow-out-of -plane

configurations

.

When the swirl intensity data is plotted relative to these vortex

centers, the distribution is shown in figures 41 (a) and (b) . These

distributions incorporate the sign-change pertinent to the counterrotation of these two vortices.

9.

Vortex Modelling. Several classic vortex models are briefly described

and fitted to our measured distributions. The one put forth by G.I.

Taylor seems to achieve the best agreement with our results to date.

The three models considered are Euler, Hamel-Oseen, and the G.I. Taylor

descriptions .[ 9 , 10] The Euler model produces a two-dimensional

tangential velocity (about the axis of rotation) that varies inversely

with distance from this axis. This is written as V = G/2jrr. This model

has the unrealistic feature of having infinitely large velocities in the

limit as r o.

8
The Hamel-Ossen distribution is a modification of the Euler version that

can be written

V =

2?rr

/I -cr\

(1 - e )

This distribution has the realistic features of zero tangential velocity

on the axis of rotation and a core of fluid rotating about the axis with

a motion resembling "solid-body" rotation.

The G.I. Taylor distribution is written:

V = (Cr) e'

This distribution does not directly exhibit the velocity variation that

is inverse with radius. Instead, it gives more emphasis to the solid

body rotation near the axis of rotation and the exponential decay further

from this axis. In our pipe flow, it appears that these features more

closely model the characteristics of our vortices.

When Taylor vortices are hypothesized to exist at+ 0.25 on either side of

the pipe centerline oh the horizontal diameter, and the core radius is

selected so that, r^ =0.2, the distribution obtained is shown in figure

42. These show the tangential velocity produced in the pipe crosssection due to each vortex. The composite flow field is obtained by

algebraic summation.

When these distributions are fitted to our data for the Z = 1.5 station

at Reynolds number 10^ the VI and V2 distributions shown on figure 43 are

obtained. The composite distribution which is the summation is shown and

labelled Va. It is noted that this approximates that given in figure 23.

Similarly, when the Taylor model is fitted to the swirl intensity

distribution shown in figure 41, the results are given in figure 44.

Again, the close resemblance gives the conclusion that our vortices

appear to be modelled by the Taylor version.

Conclusions

It is concluded from the results reported here that significant deviations are

found between the ideal, equilibriated pipe flow distributions for these

Reynolds numbers and relative roughness conditions and our measurement results

for both the "welded" and the "spaced" elbows-out-of-plane configurations.

These deviations were found in both the mean and the turbulent velocity

distributions. That these configurations can produce significant fluid

metering errors becomes clear - especially with the slow decay of these

deviations in the downstream piping.

The pressure experiments conducted in these flows indicate that increased loss

occurs due to the secondary flows produced by these piping configurations.

These losses are attributed to the fluid shearing stresses produced at the

9
inner pipe wall by these flows and the turbulent phenomena present over the

flow cross-section.

The pipe flow measurements for the single elbow indicate that a dual-eddy

secondary flow field is produced by this configuration. Although our

measurement program for this configuration is not yet complete, it is apparent

that this secondary flow pattern decays with downstream distance more rapidly

than for the elbow-out-of-plane configurations. These measurements will be

completed in the next phase of this work.

10
REFERENCES

1. Mattingly, G.E., Yeh, T.T.

,

and Robertson, B. , Flowmeter InstallationEffects: A New Approach to an Old but Prevalent Problem. Procs. Int'l

Symp . on Flow Measm't in the 1980's, NEL UK East Kilbride, Scotland U.K.

,

June 1986.

2. Mattingly, G.E., Yeh, T.T.

,

Robertson, B. and Kothari, K. , NBS Research

on In-Situ Flowmeter Installations, Procs. AGA Distribution and

Transmission Confr. Las Vegas NV, May 1987.

3. Fejer, A., Lavan, Z. , and Wolf, L. Jr., Study of Swirling Fluid Flow, ARL

68-0713, Aerospace Research Laboratories, USAF, Wright-Patterson Air

Force Base, Ohio, Oct. 1968.

4. Musolf , A.O.

,

An Experimental Investigation of the Decay of Turbulent

Swirl Flow in a Pipe, M.S. Thesis, Univ. of Colorado, Dept, of Civil

Engineering (1963).

5. Kreith, F. and Sonju, 0., The Decay of Turbulent Swirl in a Pipe, Journal

of Fluid Mechanics, Vol. 22, part 2, pp. 257-271 (1965).

6. Mottram, R.C. and Rawat, M.S., Attenuation Effects of Pipe Roughness on

Swirl and The Implications for Flowmeter Installation. International

Symposi\im on Fluid Flow Measurement, American Gas Association (1986) .

7. McManus, S.E., Bateman, B.R., Brennan, J.A., Pantoja, I.V. and Mann, D.B,

The Decay of Swirling Gas Flow in Long Pipes, Procs., AGA Distribution

and Transmission Conf. Boston, MA. May, 1985.

8. Hinze, J.O., Turbulence, McGraw-Hill, New York (1959) (Laufer's data in

chapter 7)

.

9. Schlichting, H. Boundary Layer Theory, McGraw-Hill Book Co., New York.

10. Dryden, H. , Murnaighan, F.D, and Bateman, H. Hydrodynamics, Dover Publ.

Co.

,

New York, NY 1956.

11
APPENDIX 1

NBS Indus try -Government Consortium Membership

As of the 1988 research period, the NBS Indus try -Government Consortium

Research Program on Flowmeter Installation Effects included the following

members, in alphabetical order:

1 . Ametek-McCrometer

2. Chevron Oil

3. Daniel Industries

4. Department of Energy

5. Dow Chemical Co.

6 . E . I

.

DuPont de Nemours

7. Fischer & Porter

8. Ford Motor Co.

9. Gas Research Institute

10. Gas Unie

11. Instrument Testing Service

12. ITT Barton

13. NBS-Boulder

14. Rockwell International

15. Ros amount

12
>-<u

UJD

_1

q:

if)

Table 1

Exponential

Swirl

decay

constants
t
X

Fig. 1 (a) Mean axial velocity distribution for

welded elbows-out-of-plane configuration
X

Fig. 1 (b) Mean axial velocity distribution for

spaced elbows-out-of-plane configuration
X

Fig. 2 (a) Mean vertical velocity distribution for

welded elbows-out-of-plane configuration
X

Fig. 2 (b) Mean vertical velocity distribution for

spaced elbows-out-of-plane configuration
0.20 > - ) I I I I Re=10K

+ Z=1.4

X Z=30. 6

o Z=90. 0

L+X-Y

.. +. 0. 10 ..

•.w • * O. •

+• +• .*

«o

+ . ^ 4», ^ -.X o

t •

• cf ^ o

.*.x X x K g.$.o O0.0* o* ^

•X i .©• O

^ ’ ®** A.* _ ^ K’

•9''*'-8’.o . e- o- A -o 'O

0. 00

Fig. 3 (a)

X

Turbulence axial velocity distribution

for welded elbows-out>of-plane configuration
X

Fig. 3 (b) Turbulence axial velocity distribution

for spaced elbows-out-of-plane configuration
'"0« 5 0« 0 0. 5

X

Fig. 4 (a) Turbulence vertical velocity distribution

for welded elbows-out-of-plane configuration
-0. 5 0. 0 0« 5

X

Fif. 4 (b) Turbuknct v«rticjil velocity distribution *

for spaced elbows-out-of-plane canfifuration
Sk

ew

angle,

^^9*

Skew

an

-0. 5 0. 0 0. 5

Fig. 5

X

Skew angle distribution for welded

elbows-out-of-plane configuration
-0.

5

0.

0

0-5

X

Fig. 6 Skew angle distribution for spaced

elbows-out-of-plane configuration
0.00

IIS

CNJ

O

II

N

LL

cs£

I

Axial

distribution

of

swirl

number

S,

for

Re
s s N

II

00M

ta£I IS

Axial

distribution

of

swirl

number

S,

for

Re
1

F®J«n

mt,

a\,

air

2

Mu»olf,

wat«n

3

Kn^ltph

&

Sonju,

wat.®r

4

Mot-tnam

&

Rawat^

5

NBS-GiL-^X-Y

^ 1 1 h

t ca

>-

I X

+

O CD

i I (/) (/)

CD CD

(D

+

••:|.euoo Xooep fuiMg

0

C

(0

T)

I—

0

zX

0

Q::

o>

bis

Exponential

swirl

decay

constant

versus

Reynolds

number
<D

Ol

rvj

II a I 3 < co

(Zk.3

bfi Cou

bfi c• Q.wa c

.2

(9

ota

(9

V 9)

w>S

(A

(A w.0

9ia

jCu

V

V

X

V) “O < c

(Q o
-P4,

Nvh

Location. Deg

.

Angular distributions of differential

Static pressure for welded elbow-out-ofplane configuration
-PA.

Nvh

I

Fig. 12 Angular distributions of differential

static pressure for spaced eibow-out-of~

plane configuration
L+X-Y2.42 Re-60K

• 6aQ ‘uot:iisod • 6aa 'uoi^^ sod

Pig.

13

Differential

static

pressure

distributions

for

both

piping

configurations
Friction

Factor,

A A

B c

Re/1000

Fig. 14 Variations of friction factor for welded

elbow-out-of-plane configuration
Friction

Factor,

Re/1000

Fig. 15 Variation of friction factor for spaced

elbow-out-of-plane configuration
L+X-Y

o

4. 1 ¥ 04

4- » in

^ •jo:;oed uo^^o^jj

o

o

o

Angular

averaged

friction

factors

between

the

lettered

stations

for

welded

configurations
L+X-Y2

. 42

4 4 1 - > O

CM

4- 03O

o

•jo:;oej uoi:^oxJd

o

o

o

Fig.

17

Angular

averaged

friction

factors

between

the

lettered

stations

for

spaced

configuration
L+X-Y2

. 42

BTO *0 # ‘dO

Fig.

18

The

pressure

losses

across

the

elbow

configurations
4 4 4

in o

^

0) • o o o

•

* ^

>c

^

in > I

> I 0) O J GC

s

o

#

o

4

8

O

4 "4 - -t- -4

O

o

o

ID

CM

• O

I

o

ID

0

1

A taA teo;:^jaA

Fig.

19

The

horizontal

profiles

of

the

mean

vertical

velocity

for

Re

=

10^
0.2S

4

O

4 4

ID

O

o

^

in

in o• ^

0)

o

c\j o ^

<

in > I

> I €>

CJ -J (X

o

ID

«

CM ?* • O

I A ’-taA teoT:^j0A

Fig.

20

The

vertical

profile

of

the

mean

vertical

velocity

for

Re
1.5

8

O

S

o

o

o

O X

e

?

8

O

I

M ’A^YOOtaA IB^xv

Fig.

21

The

horizontal

profile

of

the

mean

axial

velocity

for

Re

=

10^
in

o

o

o >-

in

0

1

o

II

Fig.

22

The

vertical

profile

of

the

mean

axial

velocity

for

Re
2

O

N

• O in O •

• • • • • • • o

<KK m .• • •» . X o in

1 1 1

1 N IM N

1

• » •J oc -I- X X

o

M

• •

• •

•

< k

m

m M

m M

• • • • • •

O

o

?

X

(Z m

<N

&io

CM

O o

CM

0

1

o

\D

0

1

A •*TaA IBOT^jaA

The

horizontal

profiles

of

the

mean

vertical

velocities

for

Re

=

10^
0.2S

% • • M

• N •

• m O SO O •

•Ip m o • • o • X o (O

1 1 1

•

• • > 1 N N N

.H % 1 m • • . • • , -J CL + X X

•A.

• •

g

o

s

«

«

o « w

m w

• • « •X . ^

• • •

. • • •IK iK

» •

: M y#

•• . • •

. * * |PK* ^ •

• . !«

•

• • # *« • • •

ft • • K m

-I- 4-

§

O

?

g

8 ?

A “taA leo^^jaA

O

I

Fig.

23

(b)

The

horizontal

profiles

of

the

mean

yci'f^ical

velocities

for

Re

10
g

o

o

o

o• o

?

s

0

1 0

1

• • I0A I9Ot:^J0A

Fig.

24

(a)

The

vertical

profiles

of

the

mean

vertical

velocities

for

Re

=

10^
L-Y

(0,

y,

z)

O

in O • O • • o O in

1 1 1

1

o

N N N

CL X 3IC

^ * «

• « • t ^ ^

,

. • « V * . •

• . « m M

4 I 1 » -4- —4

O

o

o

A “laA ieox:^J8A

Fig.

24

(b)

The

vertical

profiles

of

the

mean

^

for

Rg

^0^
M •*t9A Tetxv

Fig.

25

(a)

The

horizontal

profiles

of

the

mean

axial

velocities

for

Re

=

10^
2

V

/

*4^ /

f \ / f

r « «

*

* M

» *i*

« m *

^ “ * M

* *1*

+

9

\ * «

^ «« \

. \

'im ^

-

\ :

• . N

\

• • o in O • o • • o o

v‘ X o in 'T*< •

‘ • V 1 1 1 hA > 1 N N N

•V 1 o 1

r.*\ -J cr X c

ID

OJ

• O

o ID

O

O

o

!6

?

g

9 ?

X

M “laA TBTXV

Fig.

25

(b)

The

horiiontal

profiles

of

the

mean
4—4—H—4- 4—

f

-i

^

A* . /? t

/

4

I

•

\ •

» *

\

\ ^

fl M

«

• \ m M

'i -V

\

•••

. % N

• in O • . ^ • o cn

V

O O in • >• 1

1 m

1

N

1

N

H

N

CD

1

• \ ^

GC X :«( c

I < I 4

O

lO

o

8

O

8

?

g

O

o

I!

o

o

cJ

>

M "laA IBTXV

Fig.

26

(a)

The

vertical

profiles

of

the

mean

axial

velocities

for

Re
in

4- ji ^

J. i-. f/ •: ; /» +» / ^ X) / :• >o• +•+ / XC) + / • o 99 /

x6• • + / xo + / • xo 9 + / • 9 \ xb• + 1 x6 + 11 • • X 0 + 1 X 9 + 1 X b + \ • \ X 6• f \ X o 4- \ X o 4* \\ X o 4 O

V.

Hp\

.* •

•. \ + px \

HK ++ o kQ

X

M ^

ID

O • . O • • O

O

OO ^ID

-«H II It II >- II M M M I 0) II (X + O X C 4

int o

inooo >• oo

in01 M I • I8A IGTXV

Fig.

26

(b)

The

vertical

profiles

of

the

mean

axial

velocities

for

Re=

10‘
Power

spectra

of

Fif. 27 (a) Powr apactra for the turbulence

vertical velocities for Re = l(h
Power

spectra

of

Fig. 27 (b) Power spectra for the turbulence

vertical velocfties for Re = 10*
Power

spectra

of

28 (a) Poww s^Mrtra for the turbulence axial

velocities for Re = 10<
Power

spectra

of

Fig. 28 (b) Power spectra for the turbulence axial

velocities for Re = 10<
L-Y

(x.

0,

z)

Re-lOK

4

O

m

*

ID O K m

• • o *. • • ID M m • 1 u B

• • N N isl .•

• • M 4

+ X •

#

• •

• K «

M m

4 A **iaA * qjn:^ IBOTqjSA

Fig.

29

(a)

The

horizontal

profiles

of

the

turbulence

vertical

velocities

for

Re
L“Y

(x,

0,

z)

Rt-IOOK

• m

\ H *m

in O

#

• • • • . • • o

" •

1

to

1 1 T

m

N N N ^ t

-f X

• • • ^ M m

< < ¥ » -» O

o

**t 9 A ‘qjn:; iBOT^JaA

Fig.

29

(b)

The

horizontal

profiles

of

the
'

• t0A qjn:^ IGiquaeuei

Fig.

30

The

tangential

turbulence

velocity

profile

from

Laufcr*s

data,

Re

=5

x

10‘
0.20

O

ID

CU

o

o

o

o*

>

ID

CVJ

• 0

1

o

ID

0

1

I • I 0 A *qjn:^ teoiqjSA

Fig.

31

(a)

The

vertical

profiles

of

the

turbulence

vertical

veBocities

for

Re

—

1fl<
L-Y

(0.

y,

z)

Re-IOOK

o

t I 1 » 4 — » » t i

in O • • • o

in

1 1 1

N M N

+ X 3|C

4 I O

CM

• O o

in

OJ

o

o

o• o

m

cu

0

1

>

V

u

c

3

J3

u

3

V

M9

II

O

w

JU

(3

O

u

a

(Q

U• «» t

>

a

H

CT)

LL

4

O

O• O

o

to

• 0

1

,A ‘‘laA -qjn^ leott^jaA

vertical

velocities

for

Re
Laufer,

Re=.5M,

n=7.49

qjn:^ leipRy
L-Y

(x,

0.

z)

Re-lOK

O

OJ

in o •

• • o H m ^

I I I

N N N

•f X 3IC

o

II

**t0A *qjn^ TB^xv

Fig.

33

(a)

The

horizontal

profiles

of

the

turbulence

axial

velocities

for

Re
L-Y

(x.

0,

z)

in o •

• • o

^

in

^

I B I

N N N

-f X :ic

••I9A •qjn^ IBTXV

Fig.

33

(b)

The

horizontal

profiles

of

the
Laufer,

He=,5M,

n=7.49

‘*iaA • qjn:^ letxv

Pig

34

The

axial

turbulence

velocity

profile

from

Laufer's

data,

Re

=5

x

10‘
0.20

O

n

o

in

cu

• o

o

o

• >-

\D

Oi

0

1

M ••I0A "qjn^ IB^xv

Fig.

35

(a)

The

vertical

profiles

of

the

turbulence
L-Y

(0.

y.

z)

Re-IOOK

» » I - H- ¥ -

» I 1 -H ¥ O

4 1

-

in o •

. • o

^

in

^

I I I

N N N

X

>

I • ISA ‘gun^ IBixv

Fig.

35

(b)

The

vertical

profiles

of

the

turbulence

axial

velocities

for

Re

=

10^
0.20

•* •%

% H

. '

•

• •

• •

• • • • H#*

N

*<%

-4..

* e

* V

Q O K •>

^ • K

• •

• • -X ^

• • O in O •

• • M •

• • o •

* X o in

K m 1 1 1

• •

• • > 1 N N N

K • 1 0) • •

• • -J cc -h X X —»- Oo

o

AM ‘xnnd M3>1S

X

o

Fig.

36

(a)

The

horizontal

profiles

of

skew

flux

for

Re
.K

N

m O in O • • o • • o

r X o in

•

• 1 1 1

• > 1 N N N •

•

* 1 0)

• « -J CL + X X

/ .

o •

X <•»

* V

g

o

in

CVJ

o

o• o

in

CVJ 0

1

o

in

o

CVI ?* 0

1

X

AM ‘Xnid M3XS

Fig.

36

(b)

The

horizontal

profiles

of

skew

flux

for

Re
0.20

N

>% in O m • # O

o o in ^rH

1 1 1

1 N N N

1 0)

-1 cr + X

» •« .

• • % H

f

m

m

*

M

M

« <#

«

• •

» «

•

• o

• • • ?*

t f

o

n• o

ID

CU

o

o• o

ID

CU

• 0

1

o

o

o

ID

O

OJ ?* 0

1

>-

o

II

AM ‘xmd M3XS

Fig.

37

(a)

The

vertical

profiles

of

skew

flux

for

Re
L-Y

(0,

y,

z)

Re-IOOK

O

I

o

\D

tn

cu

• o

o

o• o

in

cu

• 0

1

o

tt)

o

cn

Y'

• 0

1

o

II

>

AM 'Xmd M3>IS

Fig

37

(b)

"Fbc

vertical

profiles

of

skew

flux

for

Re
• • N

o in o • ^ ^ • • o

^X o in ^ III

>- I N N N

I 0)

-j cr + X X

M

-4- > t < o

4 I \ < —f

O

OJ

I

o

in

• 0

1

• 69Q 'ai6ue Ma>is

X

©

II

Fig.

38

(a)

The

horizontal

profiles

of

skew

angle

for

Re
. H

%

%

O

II

*

o

o• o X

f*

#•* #

• •

« #

o

• 68Q

N

m O x: in O • o • • o

X o in

1 1 1

> 1 N N N

1 0)

-J cr + X X

*ax6ue m3>{S

?

2

O

cu

^*

I

Fig.

38

(b)

The

horizontal

profiles

of

skew

angle

for

Re
L-Y

(0.

y.

z)

Re-lOK

-» 1—H 1 >

mii

0 • 9H

• • at M

+—< -4 -H

*» M

K

• <

« >t

.

* • *

^.

* • mrn4>

9 ^ *® f • •• m

4—»-

in o • • • o ^

in

^

I I I

N N N

•f X

o

• 6aa

0

1 ‘ai6ue Ma>is

O

lO

o

in

OJ

o

in

cu

• 0

1

0

CVJ

1

o

m• 0

1

o

II

o

o

d

>-

Fig.

39

(a)

The

vertical

profiles

of

skew

angle

for

Re
L-Y

(0,

y,

z)

Re-IOOK

m wi

• in O •

• •

•

• • mm

• • o

• •^ • in

• . • 1 1 1 mm •

• « N N N

# • • • + X :ic

m

"» I —f —»- < < O

I *6aa *at6ue Ma>is

m

Oi

0

1

Fig.

39

(b)

The

vertical

profiles

of

skew

angle

for

Re
g

o

lO

OJ

o

o

o• o

?

#

o o 0

1

X

XAM=dS ‘TJTMS

Fig.

40

(a)

The

distributions

of

the

swirl

intensity

a

hoiit

rh#»

ni-Qg

r<»nr

Ariaini<*

in4
L-Y

(x,

0,

z)

Re-IOOK

+ f

X m • .

• . M m

• • m

• • • •

• •• . •

• .

.

O

to

o

to

CVJ o

m

* I o

o• o

f

• • K« • • • • »cai

in O • • • o

in

1 1 1

N ISI N

+ X

in

cu

• 0

1

9 O

O

o

o

XAM-dS ‘IJTMS

o

to

2 ?

0

1

Fig.

40

(b)

The

distributions

of

the

swirl

intensity

about

the

pipe

centerline

for

Re

=

10*^
o

to

• o

to

CM

o

o

o• o

8

?

X

(OJ-J) AM=as ‘IJTMS

Fig.

41

(a)

The

distributions

of

the

swirl

intensity

about

the

hypothesized

vortex

centers

for

Re

=

10<

‘
0.06

O

in

o

in

OJ

o

o

o

O

OJ

.*! ?

o

»

0

1

X

o

(OJ-J) aM=as 'TJIMS

Fig.

41

(b)

The

dlstributiong

of

the

gwirl

Intensity

about

the

hypothesized

vortex

centers

for

Re

=

10‘
GI

Taylor

vortex

KM

cu

CU ^

in

CVi \ o

lO• o

to

cu• o

in• in I CUI^

cu

r • dX

0)X 0) C -P 0) ICC.

0) o

Li.

OO

K

X oo# o KXK

lO

cu• 01

'4 o

cu• o

-+ I 4 » -t- -». - f t I I t » o O

CU 9 o 01

ID9 01

Fig.

42

Taylor

vortex

velocity

distribution

based

on

the

hypothesized

paramgrgrs
0.20

to

o

to

C\i

o

o

o

to

OJ

0

1

o

ID

0

1

X

o

# 0

1 A^TOOtaA xa^JOA

Fig.

43

Velocity

distribution

obtained

by

fitting

data

to

Taylor

vortex

model

for Z

=

1.5

and

Re

=

10*
o.os

{]

O O

I

O

lO

o

o

o

o

ID

04

• 0

1

o

to

• 0

1

X

;s ‘t j;ms xa^jOA

Fig.

44

Swirl

intensity

distribution

based

on

the

Taylor

vortex

model
NBS«n4A (BEv. 2 ««ci U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

1. PUBLICATION OR

REPORT NO.

2. Performing Orgam. Report No. 3. Publication Date

SHEET (See instructions) NISTIR 88-3898 NOVEMBER 1988

4. TITLE AND SUBTITLE

NBS Industry - Government Consortium Research Program on Flowmeter Installation

Effects Semi Annual Report: 1987 II

5. AUTHOR(S)

G.E. Mattingly and T.T. Yeh

6. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions) 7. Contract/Grant No.

national bureau of STANDARDS

DEPARTMENT OF COMMERCE 8. Type of Report & Period Covered

WASHINGTON, D.C. 20234

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, State, ZIP)

10.

SUPPLEMENTARY NOTES

I

I Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11.

ABSTRACT (A lOO^y^ord or less factual summary of most significant information. If document includes a si gnifi cant bibliography or literature survey, mention it here) This report presents results produced in 1987 in a

consortium— sponsored research program on Flowmeter Installation Effects. This project

is a collaborative one that is supported by an industry-government consortium that meets

twice yearly to review and discuss results and to plan subsequent phases of the work.

This report contains the. results and conclusions of the recent meeting of this consortiuii

at NBS-G on Feb. 17, 19o8.

The objective of this research program is to produce improved flowmeter perfomance

when meters are installed in "non-ideal conditions. This objective is being attained

via a stategy to (A) measure, understand, and quantify the non-ideal pipeflows from

such pipeline elements as elbows, reducers, valves, or combinations of these, (B) for

selected types of flowmeters, correlate meter factor "shifts" relative to the features

of these "non-ideal" installations, and (C) disseminate the resulting technology through

appropriate channels such as publishing our results in pertinent journals and upgrading

"paper" standards for flow measurement.

Specific results included in this report include:

1. the distributions of the mean and the turbulence velocities in the axial and

vertical directions in both the (closely coupled) elbows-out-of-plane piping

configuration and the "spaced" version of this arrangement,

2. the pressure loss measurements for both of the elbow-out-of-plane configurat

and

3. the velocity distributions produced by the single elbow piping configuration

12.

KEY WORDS fS/x to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semi colon s) Flowmeter; Installation effects; pipeflow; Secondary flows; Swirl

13. AVAILABILITY

y i Uni imited

For Official Distribution. Do Not Release to NTIS

:

I Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

2_ Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

82

15. Price

$13.95

USCOMM-DC 8043-P80
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