Group Title: 7th International Conference on Multiphase Flow - ICMF 2010 Proceedings
Title: P1.42 - Fluctuation characteristics of terrain-induced slug flow in flexible riser: an experimental investigation
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 Material Information
Title: P1.42 - Fluctuation characteristics of terrain-induced slug flow in flexible riser: an experimental investigation Computational Techniques for Multiphase Flows
Series Title: 7th International Conference on Multiphase Flow - ICMF 2010 Proceedings
Physical Description: Conference Papers
Creator: Li, N.
Guo, L.
Zhang, X.
Wang, Y.
Chen, S.
Ye, J.
Han, P.
Ma, K.
Li, W.
Publisher: International Conference on Multiphase Flow (ICMF)
Publication Date: June 4, 2010
 Subjects
Subject: terrain-induced slug flow
fluctuation characteristics
flexible risers
severe slugging
 Notes
Abstract: Terrain-induced slug flow in terms of severe slugging flow can occur in pipeline-riser systems operating at low liquid and gas rates, leading to an undesirable cyclic operation. Knowledge of fluctuation characteristics of severe slugging is essential for the design and operation of topsides separation and storage facilities. In this paper, an experimental study has been conducted to investigate the fluctuation characteristics caused by severe slugging in flexible riser. The test pipeline consisted of a 114-m horizontal section, a 16-m long, 2-degree downward inclination section, and a flexible riser. The riser was in a lazy S-shaped configuration, with a total height of 15.3-m and a total length of 24-m. Experimental data were used to characterize the cyclic fluctuation behaviour of terrain-induced slug flow. It was found out that in a similar way to the characteristic of severe slugging in vertical and catenary riser, the cycle of typical severe slugging in an S-shaped riser is broken into four steps including liquid buildup, liquid production, gas penetration, and fluid blowout. Moreover, under the flow regime of typical severe slugging, not only the riser outlet pressure and liquid production behave a cyclic fluctuation characteristic, but also the pipeline inlet pressure and inlet fluid flowrates.
General Note: The International Conference on Multiphase Flow (ICMF) first was held in Tsukuba, Japan in 1991 and the second ICMF took place in Kyoto, Japan in 1995. During this conference, it was decided to establish an International Governing Board which oversees the major aspects of the conference and makes decisions about future conference locations. Due to the great importance of the field, it was furthermore decided to hold the conference every three years successively in Asia including Australia, Europe including Africa, Russia and the Near East and America. Hence, ICMF 1998 was held in Lyon, France, ICMF 2001 in New Orleans, USA, ICMF 2004 in Yokohama, Japan, and ICMF 2007 in Leipzig, Germany. ICMF-2010 is devoted to all aspects of Multiphase Flow. Researchers from all over the world gathered in order to introduce their recent advances in the field and thereby promote the exchange of new ideas, results and techniques. The conference is a key event in Multiphase Flow and supports the advancement of science in this very important field. The major research topics relevant for the conference are as follows: Bio-Fluid Dynamics; Boiling; Bubbly Flows; Cavitation; Colloidal and Suspension Dynamics; Collision, Agglomeration and Breakup; Computational Techniques for Multiphase Flows; Droplet Flows; Environmental and Geophysical Flows; Experimental Methods for Multiphase Flows; Fluidized and Circulating Fluidized Beds; Fluid Structure Interactions; Granular Media; Industrial Applications; Instabilities; Interfacial Flows; Micro and Nano-Scale Multiphase Flows; Microgravity in Two-Phase Flow; Multiphase Flows with Heat and Mass Transfer; Non-Newtonian Multiphase Flows; Particle-Laden Flows; Particle, Bubble and Drop Dynamics; Reactive Multiphase Flows
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Volume ID: VID00450
Source Institution: University of Florida
Holding Location: University of Florida
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Resource Identifier: P142-Li-ICMF2010.pdf

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Paper No 7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010


Fluctuation characteristics of terrain-induced slug flow in flexible riser: an experimental
investigation


Nailiang Li, Liejin Guo, Ximin Zhang, Yueshe Wang, Senlin Chen, Jing Ye, Pengfei Han,
Keshuai Ma and Wensheng Li

State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University
Xi'an 710049, China
E-mail: lj -guo a Iail.xjtu.edu.cn



Keywords: terrain-induced slug flow, fluctuation characteristics, flexible risers, severe slugging




Abstract

Terrain-induced slug flow in terms of severe slugging flow can occur in pipeline-riser systems operating at low liquid and gas
rates, leading to an undesirable cyclic operation. Knowledge of fluctuation characteristics of severe slugging is essential for the
design and operation of topsides separation and storage facilities. In this paper, an experimental study has been conducted to
investigate the fluctuation characteristics caused by severe slugging in flexible riser. The test pipeline consisted of a 114-m
horizontal section, a 16-m long, 2-degree downward inclination section, and a flexible riser. The riser was in a lazy S-shaped
configuration, with a total height of 15.3-m and a total length of 24-m. Experimental data were used to characterize the cyclic
fluctuation behaviour of terrain-induced slug flow. It was found out that in a similar way to the characteristic of severe
slugging in vertical and catenary riser, the cycle of typical severe slugging in an S-shaped riser is broken into four steps
including liquid buildup, liquid production, gas penetration, and fluid blowout. Moreover, under the flow regime of typical
severe slugging, not only the riser outlet pressure and liquid production behave a cyclic fluctuation characteristic, but also the
pipeline inlet pressure and inlet fluid flowrates.


Introduction

Floating Production Storage and Offloading (FPSO) system
is commonly used in offshore platforms, especially in
deepwater oilfield since it's more economical than
fixed-tower and tension-leg platforms (Manning and
Thompson, 1995). Flexible risers which can be designed as
free-hanging catenary or S-shaped configurations are
essential components of floating production system since
they can transfer the hydrocarbon from the seabed to the
topside facilities.
Gas-liquid two-phase flow is often encountered in
transportation pipelines of oil fields. In offshore oil fields,
the produced fluids are often firstly transported over long
distances and then through a flexible riser for subsequent
separation and processing. Slug flow is one of the most
common flow patterns in pipeline-riser system. An accurate
understanding of flow characteristics is not only essential to
improve the design, sizing and routing of pipes, but is also
necessary for the design of the downstream separation and
processing facilities.
Gas-liquid two-phase slug flows can be classified into two
main groups: hydrodynamic slugging and terrain-induced
slugging. Hydrodynamic slugging is the normal slugging
pattern encountered in straight flow lines. Terrain-induced
slugging results from liquid accumulation in local dips of
flow lines with variable topography. The accumulated liquid
blocks the passage of gas, forming long liquid bridges that


can be blown out from one pipeline section to the next by
the gas pressure.
Terrain-induced gas-liquid two-phase slug flow in terms of
severe slugging flow is a common phenomenon in offshore
pipeline-riser system. Much of the work related to
terrain-induced slug flow is restricted to the study of severe
slugging in pipeline-riser systems. In offshore petroleum
exploration and production industry, severe slugging
phenomenon which characterized by fluctuations in
pressure and flow rate will occur when the pipeline-riser
system operating at relatively low liquid and gas flowrates
(Schmidt et al., 1980, 1985). Liquid slugs generated in riser
ranges in length from one to several riser-pipe heights,
causing overflow and shut down of the topsides separator
due to the large volume of liquid production (Farghaly,
1987). Moreover, fluctuations in fluid flowrate might induce
riser oscillation, and the high pressure fluctuations might
cause operational problems and reduce the production
capacity of the field (Fabre, J et al., 1990).
Severe slugging in vertical riser has been studied both
experimentally and theoretically by a number of authors.
Schmidt et al. (1985) described the process in four-step
cycle as follows: slug formation, slug movement
(production into the separator), blow out and liquid fall back.
Pots et al. (1985) made an experimental study on a
small-scale facility and discussed the physics of severe
slugging. Taitel et al. (1990) performed an observation
study on a small-scale test facility and found that when the






7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010

riser. Kashou (1996) reported the compared results of
OLGA code predictions with data generated from the
Multiphase Pipeline and Equipment (MPE) joint industrial
project. Comparisons have been carried out for two riser
configurations catenaryy and lazy S) with the outlet pressure
boundary specified at atmospheric pressure. Simulated
results agreed well with experimental data except for
detailed severe slugging characteristics such as the peak
production rate, the steady production rate, and the pressure
cycling characteristics.
As most of the new discoveries of oil and gas reserves are
expected to occur offshore, exploration and production of
offshore petroleum reservoirs will head into deeper waters.
Therefore, floating production facilities will be encountered
more frequently in offshore petroleum industry. While
severe slugging flow is relatively well understood for the
configuration of vertical riser and free-hanging catenary
riser, there is a lack of understanding of flow characteristics
in S-shaped riser. The objective of this article is to
investigate fluctuation in characteristics at system inlet and
outlet of terrain-induced slug flow in an S-shaped flexible
riser system experimentally.
As described by Tin and Sarshar (1993), different types of
severe slugging can be presented in S-shaped riser, such as
typical severe slugging and transition severe slugging.
However, only typical severe slugging is taken as an
example to characterize the instability in this paper.


Paper No


liquid column is stable there is still a tendency for a cyclic
process to occur. However, this cyclic process can be
damped and become a steady flow. It was also found that in
the region predicted by the Boe criterion (Boe, 1981) to be a
steady flow, the flow can be unstable and lead to a severe
slugging type of behaviour. Wang et al. (2005, 2006) studied
severe slugging experimentally and theoretically and
presented different flow pattern maps. Distinct instabilities
in severe slugging and periodically fluctuated flow
characteristics were observed. Moreover, it was found out
that severe slugging would occur even when the slope of the
downward pipeline was zero. A new theoretical model was
also developed to predict the characteristics of gas-liquid
flow in the pipeline-riser system, the results agreed very
well with experimental data.
Tin and Sarshar (1993) first reported an experimental
investigation of severe slugging in flexible riser. The
experimental study was carried out with air and water on
three different riser configurations, including free-hanging
catenary, lazy S, and steep S riser shapes. It was found that
the pressure cycling characteristic of severe slugging in an
S-shaped riser varies significantly from that found in
vertical risers, and can be considered as two free-hanging
catenary risers connected together with each riser having
independent effects on the cycle. In contrast, the
experimental study on severe slugging in S-shaped riser
performed by Montgomery (2002) revealed that the cycling
characteristic behaves in a similar way to that in vertical


Downward inclined pipeline


1 -centrifugal pump; 2 -gear pump; 3 -screw compressor; 4 -electromagnetic flowmeters;
5 -mass flowmeters; 6 -pressure stability tank; 7 -vortex flowmeter; 8 -orifice plate flowmeters;
9 -mixing tee; 10 -pressure transducers; 1 1 -gamma ray densitometer; 12 -ball valve;
13--gas-liquid separator; 14--oil-water separator
Figure 1: Schematic diagram of the experimental facility.


The experimental study was carried out on oil-water-air
multiphase large scale loop located at State Key Laboratory
of Multiphase Flow in Power Engineering in Xi'an Jiaotong
University. The experimental facility illustrated in Figure 1


consists of a horizontal pipeline, a 16-m long, 2-degree
downward pipeline and a flexible riser which was in a lazy
S-shaped configuration. The horizontal pipeline was 114-m
long, so that a fully developed flow can be ensured. The


Experimental Facility

11 10






7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010

risers (Montgomely et al, 2002; Mokhatab, S 2005), the
pressure difference cycling for severe slugging in S-shaped
riser is generally made of four basic stages: liquid buildup in
both lower and upper limbs, steady liquid production, the
penetration of gas bubble into riser base, and the stage of
fluid blowout and liquid falls back.
Stage.1. Liquid buildup in the riser Liquid accumulates in
the riser and blocks the passage of gas due to liquid fallback
and to liquid inflow from upstream pipeline. During this
stage, the liquid buildup phenomenon first occurs in the
lower limb and then in the upper limb, and the pressure
difference over the riser increases. In addition, no liquid is
produced into separator so that liquid holdup at riser outlet
maintains zero.
Stage.2. Steady liquid production This stage occurs as
soon as both of the two upward limbs are filled with liquid.
Slug begins to flow out of the riser and into separator. This
is the stage during which gas blocked in the downward
inclined pipeline is still be compressed and the increasing
tendency of the pressure continues.
Stage.3. Gas penetration At the end of liquid production
stage, the pressure of gas accumulated both in downward
inclined pipeline and in downward limb becomes sufficient
enough to push gas bubble into the base of lower and upper
limb, respectively, inducing the pressure difference over the
riser drops (Point A in Figure 2).
Stage.4. Fluid blowout and liquid falls back Large amount
of gas enters into riser rapidly, hence accelerates the
flowrate of liquid to its maximum value, leading the mixture
of gas and liquid moves insurgently. Towards the end of the
fluid blowout, the gas pressure decreases due to the
reduction of gas amount and becomes insufficient to support
the liquid on the riser walls. On the effect of gravity, the
phenomenon of liquid falling down into the riser bottom
occurs. This is a short period during which the gas
production occurs and riser oscillates intensively.
However, this special configuration of riser has effect on the
flow behaviour in the limbs, and there are some differences
between S-shaped riser and vertical or catenary risers. As
can be seen in Figure 2, during the stage of liquid
production, the pressure of lower limb base first drops
(Point B) due to penetration of bubble into riser base and
then increases due to liquid that falls down in this limb.
However, the liquid production at riser outlet continues and
will not be terminated until gas bubble penetrates into the
base of the upper limb.


Paper No


downward inclined section was in a length of 16-m, which
allow the stabilisation of the pipeline flow regime before
ently into the riser base and provide sufficient gas
compressible volume for severe slugging to occur. The total
height of the riser was 15.3-m. The horizontal and
downward inclined pipeline sections were made of stainless
steel pipe, while the S-shaped riser were made of plastic pile
and were transparent for visual observation. The inner
diameter of the test loop was 50-mm.
The working fluids in operation were water and air, hence,
only water and air supply and measurement system were
used. Water was supplied from storage tank by centrifugal
pump and measured by an electromagnetic flowmeter with
precision of 0.5%, air was first compressed by the screw
compressor into a buffer vessel, then filtered and measured
by an orifice plate before introducing into gas-liquid mixer.
At the outlet of the riser, the gas-liquid mixture was
separated in a separator which was operated under
atmospheric condition. The water was recycled back to the
storage tank while air was vented to atmosphere.
The instrumentations for measurement including Keller
pressure and differential pressure transducers (accuracy
0.1%) installed along the loop, a gamma ray densitometer
located at riser outlet was also used for a better investigation.
Pressure measurements were made mainly at the pipeline
inlet, bottom of each upward limb, top of the downward
limb and riser outlet, while pressure difference
measurements were made over the two upward limbs. Data
was collected and recorded using an NI acquisition board
with the help of NI LabView 8.2 software and transmitted to
a personal computer. All the concerned signals were
sampled at the frequency of 200 Hz.


Results and Discussion

Fluctuation in pressure difference during severe
slugging


23 -Pressure difference over the whole riser
210-Stg3
19. Stagel Stage2
S170.


S130- Stage4
1110-
S90 -

500 600 700 800 900 1000
t [s]

Figure 2: Pressure difference profile over the whole riser
during typical severe slugging.

Pressure trace at riser base is commonly used for
identification and characterization for severe slugging.
However, it's found that the pressure difference over the
riser can characterize severe slugging, too. A typical
pressure difference trace over the whole riser for severe
slugging is shown in Figure 2. In a similar way to the
characteristics in vertical (Schmidt et al, 1985) and catenary


260
-240
220
-200
-180
-160
140
S120
900 1000


500 600 700 800
t [s]


Figure 3: Pressure difference profile between point A and
riser outlet during severe slugging.







































































-Probability density
of Ilquid holdup at riser outlet









S I I I I I~
1 0.1 0.3 0.5 0.7 0.9 1
Liquid holdup


7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010

Firstly, the liquid accumulates both in the upper and lower
limb and lift towards to riser outlet due to the pressure of the
riser base increases; this gives the period of no liquid
production. When the front of liquid column reaches the top
of the upper limb, the constant liquid production period
begins. As soon as the gas enters the riser, the liquid is
accelerated and transient production period occurs, this
period corresponds to the gas blowout stage of the severe
slugging pressure cycling. The maximum liquid flowrate of
riser outlet can be several times of system inlet mixture
flowrate. However, the transient liquid production is
harmful to topsides facilities.


Liquid holdup at riser outlet





02-



0200 400 600 800 1000 1200 1400 1600
time [s]

Figure 6: Liquid holdup local to riser outlet.

Apart from pressure and pressure difference trace variation
analysis, the liquid holdup local to riser outlet was also
measured for a better appraisal of the flow phenomena. It
has been normalized so that liquid holdup corresponding to
the presence of liquid phase only equals to 1, and liquid
holdup indicating the presence of gas phase only equals to 0.
Therefore, the sharp liquid holdup transitions indicate the
interfaces between gas and liquid.
Severe slugging is a cyclic process which results in a period
of no liquid production into the separator occurs, followed
by a period of very high liquid production (Montgomery et
al, 2002) This feature results in a square wave signal of
liquid holdup local to riser outlet, as is shown in Figure 6. It
COnfirms the characteristic of periodic fluctuation in fluid
production caused by severe slugging. This phenomenon is
undesirable in real offshore pipeline-riser system since
fluctuations in liquid and gas production might cause shut
down of the separator and operational problems during
flaring, respectively.


Paper No


As stated previously, in the third stage, liquid column is
accelerated due to the penetration of large amount of gas
into riser, as proved in Figure 3. The sharp increases and
drops in pressure difference over riser outlet and the
location immediately upstream indicates gas penetration
occurs. It's a short period after which large amount of gas
flow into the riser, causing fluid blowout and liquid falls
back.

Fluctuation in pressure of riser outlet

The pressure at riser outlet behaves a cyclic characteristic
during severe slugging, as shown in Figure 4. During the
period of liquid buildup and liquid production, the pressure
of riser outlet equals to that of separator downstream which
was operated under atmospheric condition. In the period of
fluid blowout, there is a sharp increase in the pressure due to
the fast movement of liquid slug.


111 260
Pressure of rlser outlet
S112 - Pressure of rlser base -( 240 E
$- 220 a
110 -
-200
S108- -
-I~ ~ ~ ~ I 180 ~
~106-
-160

S104- 140 g
102 120
0 200 400 600 800 1000
t [s]

Figure 4: Riser outlet pressure profile during typical severe
slugging.

Fluctuation in liquid production at riser outlet


260
tlet -240

220

-200 u
-180

-160
140

I 120
1500 2000



during typical severe


0.6

0.5

0.4
L.
o 0.3-
0.2

0.1

0.0


0 500 1000
time [s]


Figure 5: Liquid production profile
slugging.


Figure 5 shows an example of the liquid production profile
during typical severe slugging. The superficial gas and
liquid velocity is 0.1m/s and 0.15m/s, respectively. Similar
to severe slugging in vertical and catenary risers (S.
Mokhatab), the liquid production is also characterized by
three main periods: the period of no production, the period
of constant liquid production, and the transient production
period.


Figure 7: PDF curve corresponding to liquid holdup.






Paper No


The probability density function (PDF) analysis is a well
established technique for time series analysis of signals. In
the present study the PDF curve is plotted with the PDF
values corresponding to the liquid holdup as the ordinate
and the liquid holdup as the abscissa, as can be seen in
Figure 7.
Severe slugging causes periodic production of liquid as is
evident from the bimodal PDF curve obtained from the
signals of liquid holdup measured at riser outlet during
severe slugging.

Fluctuation in pipeline inlet pressure


300
-Pipellne Inlet pressure
280 -
260
S240
~220 -
S200


160 -
600 800 1000 1200 1400 1600
time [s]

Figure 8: Time trace for the pipeline inlet pressure during
typical severe slugging.

Though severe slugging in both vertical and flexible riser
has been studied by a number of researchers, the effect of
cyclic fluctuation on pipeline inlet pressure and inlet
flowrates during severe slugging has rarely been reported.
Figure 8 shows pipeline inlet pressure variation during
typical severe slugging. Similar to that of riser base, the
pressure of pipeline inlet fluctuation cyclically. The
maximum magnitude of pressure fluctuation was 44.8%.

Fluctuation in pipeline inlet flowrates


7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010

system pressure fluctuation and pipeline inlet fluids velocity
present a cyclic characteristic. However, gas velocity seems
to be less sensitive to cyclic fluctuation of pressure probably
due to its property of compressibility.


Conclusions

The fluctuation characteristics of terrain-induced slug flow
in a flexible riser were studied experimentally. The process
of terrain-induced severe slugging in an S-shaped riser can
be split into four main stages; (1) liquid buildup and slug
formation, (2) slug production, (3) bubble penetration, and
(4) gas blowdown and liquid falls back.
In the flow regime of typical severe slugging, the time trace
of liquid holdup local to riser outlet presents a squre wave
shape, indicating periodic production of liquid into the
separator.
Severe slugging occurs at low liquid and gas velocity,
resulting in fluctuation not only in riser outlet pressure and
fluids production, but also in the pressure and fluids
flowrate at pipeline inlet. Harm from the cyclic fluctuation
of pressure and fluid flowrates may cause operation
problems of the topsides and bottom hole facilities.


Acknowledgements

The supports for this work by the National Natural Science
Foundation of China (Contract Nos. 50821064, 50823002)
are gratefully acknowledged. The authors also wish to
acknowledge the people who made contributions to this
research work.


References

Manning, F. S., Thompson, R. E. Oil Field Processing, Vol.
2: Crude Oil. Tulsa, OK: Pennwell Publishing Company
(1995)

Schmidt, Z., Doty, D.R., Dutta Roy, K., Severe slugging in
offshore pipeline-riser pipe system. SPE J 12334, 27-38
(1985)

Schmidt, Zelimir; Brill, James P.; Beggs, H.Dale.,
Experimental study of severe slugging in a two-phase-flow
pipeline-riser pipe system. Society of Petroleum Engineers
journal, n 5, 407-414, Oct (1980)

Farghaly, M. A. Study of Severe Slugging in Real Offshore
Pipeline Riser-Pipe System. SPE J 15726, 299-314 (1987)

Fabre, J., Peresson, L., Corteville, J., Bemicot, M., and
Ozon, P. Severe slugging in pipeline/riser systems. SPE
Production Engineering, 5:299-305 (1990)

Pots, B. F. M., Bromilow, I. G, and Konijn, M. J. Severe
Slug Flow in Offshore Flowline/Riser Systems. Paper
presented at SPE Middle East Oil Technical Conference &
Exhibition, Bahrain. SPE 13723, 347-356 (1985)

Taitel, Y., Vierkandt, S., Shoham, O., and Brill, J. P. Severe


S0.100
S0.098
~0.096
0.094
0.092
0.090 I ,
0 200


Figure 9: Pipeline inlet
severe slugging.


260 I
240 a
220 E
200
180
I I I 160
400 600 800 1000
time [s]

flowrates variation during typical


Figure 9 illustrates the variation pipeline inlet flowrates
during typical severe slugging, riser base pressure is also
presented for a better comprehension. As can be seen, both
liquid and gas flowrates at pipeline inlet are influenced by






Paper No 7th International Conference on Multiphase Flow
ICMF 2010, Tampa, FL USA, May 30-June 4, 2010

slugging in a riser system: Experiments and modeling.
International Joumnal of Multiphase Flow, 16:57-68 (1990)

Boe, A. Severe Slugging Characteristics. Part 1: Flow
regime for severe slugging; Part 2: Point model simulation
study [A]. Presented at Selected Topics in Two-Phase
Flow[C], Norwegian Institute of Technology (NTH),
Trondheim, Norway (1981)

Wang, Xin; Guo, Lie-Jin; Zhang, Xi-Min; Gu, Han-Yang;
Lin, Chang-Zhi; Zhao, Dong-Jian; Guo, Fu-De.
Experimental study of severe slugging in pipeline-riser
system. Journal of Engineering Thermophysics, v 26, n 5,
799-801, September (2005)

Wang, Xin; Guo, Lie-Jin. Experimental investigation and
simulation of severe slugging in pipeline-riser system.
Journal of Engineering Thermophysics, v 27, n 4, 611-614,
July (2006)

Tin, V., Sarshar, S. An investigation of severe slugging
characteristics in flexible risers. Proc. 6th Intemnational
Conference on Multiphase Production, Cannes, France,
205-227 (1993)

Montgomery, J. A., Yeung, H. C. The Stability of Fluid
Production From a Flexible Riser, Joumnal of Energy
Resources Technology, V124, 83-89 (2002)

Kashou, S. Severe Slugging in an S-Shaped or Catenary
Riser: OLGA Prediction and Experimental Verification.
Paper presented at Advances in Multiphase Technology
Conference, Houston, TX, June 24-25 (1996)

Mokhatab, S. Severe slugging in a catenary-shaped riser:
Experimental and simulation studies. Petroleum Science and
Technology, v 25, n 6, 719-740, June (2007)




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