Crisman Annual Report 2009 - Harold Vance Department of ...

Investigation of Swirl Flows Applied to the Oil and Gas Industry
Introduction
Swirl flow (or vortex flow) is a fluid stream which has
a rotational velocity as well as a linear velocity (Fig.
1). It typically occurs in cyclones, hydrocyclones,
spray dryers, heat exchangers with twisted-tape
inserts, and vortex burners. It is also the basic
principle behind foam-breaking or de-foaming
separators, which have received significant industrial
attention in recent years. Current research at Texas
A&M University is studying the various applications
of swirl flow to help mitigate particular problems
in the oil and gas industry. Among the swirl flow
applications under investigation are liquid unloading
in gas wells and wet gas metering.
Swirling Flow
For the purpose of the analysis presented here, the
expansion/contraction section and the venturi were
excluded from the simulations in order to allow focus
on the effects of the swirling device.
In prior described experiments (Falcone et al.,
2003), the actual length of straight pipe upstream
of the swirler was about 10 m. This resulted in fully
developed annular flow prior to the fluid reaching
the swirler. To simulate this correctly with the CFD
model while minimizing the mesh requirements
(and hence the running times), a sensitivity analysis
was performed on the length of pipe to be modeled
before the swirler. It was found that a length of 2
m in the model yielded annular flow upstream the
swirler. The final model used for the CFD simulations
is shown in Fig. 2.
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Axial Flow
Direction
Fig. 1. Schematic of a swirl flow, showing a particle’s helical path.
Objectives
A commercial CFD software package will be used
in this study, with the objective of investigating
the efficiency of the liquid separation at high gas
fraction and evaluating the persistence of the swirl
downstream of the flow conditioning device. These
features are essential to understand not only the
efficiency of in-line separation devices used for wet
gas metering purposes, but also that of downhole
tools for liquid unloading in gas wells.
Approach
A commercial CFD software package was used.
A model of the ANUMET meter was built and
simulations were run using the input data from the
reported experiments (Falcone, 2006). The pipe
diameter was increased from 31.8 mm to 32.1 mm,
which provided a 0.15 mm thick inflation boundary
on the pipe walls that helped to capture the film
thickness more efficiently than tetrahedral elements.
Project Information
2.4.17 Investigation of Swirl Flows Applied to the Oil and
Gas Industry
Related Publications
Falcone, G., Hewitt, G.F., Lao, L., Richardson, S.M. ANUMET:
A Novel Wet Gas Flowmeter. Paper SPE 84504 presented at
the 2003 SPE Annual Technical Conference and Exhibition,
Denver, Colorado, 5-8 October.
Surendra, M., Falcone, G., Teodoriu, C. Investigation of
Swirl Flows Applied to the Oil and Gas Industry. Paper
SPE 115938 presented at the 2008 SPE Annual Technical
Conference and Exhibition, Denver, Colorado, 21-24
September.
Contacts
Gioia Falcone
979.847.8912
gioia.falcone@pe.tamu.edu
Catalin Teodoriu
catalin.teodoriu@pe.tamu.edu
Meher Surendra
CRISMAN INSTITUTE
Crisman Annual Report 2009
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