Simplified surge pressure model for yield power law fluid in eccentric annuli

Simplified surge pressure model for yield power law fluid in eccentric annuli Axial movement of drillstring during drilling operations causes downhole pressure variations, which are commonly known as surge and swab pressures. This paper presents a new eccentric annulus surge pressure (EASP) model for yield power law (YPL) fluid. To develop the model, flow in eccentric annulus was investigated using computational fluid dynamics (CFD) technique (ANSYS Fluent). CFD simulations were conducted varying fluid rheological parameters, tripping speed and annular geometry. Simulation results are analyzed considering surge pressure ratio (i.e. ratio of surge pressure in eccentric annulus to that of concentric annulus) as a parameter for quantifying effect of eccentricity on surge pressure. Surge pressure ratio (SPR) is found to be very sensitive to fluid behavior index and annular eccentricity and diameter ratio. In addition to the CFD studies, small-scale laboratory experiments were conducted to validate accuracy of the EASP model. Results show that the model accurately (i.e. maximum error of ±5%) and conveniently predicts surge and swab pressures for YPL (Herschel Buckley) fluid in eccentric annulus without requiring complex numerical procedures. The model is valid for wide ranges of diameter ratio (0.2≤Kd≤ 0.8), eccentricity (0≤ ε≤0.9) and fluid behavior index (0.2≤n≤ 1). http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Petroleum Science and Engineering Elsevier

Simplified surge pressure model for yield power law fluid in eccentric annuli

Loading next page...
 
/lp/elsevier/simplified-surge-pressure-model-for-yield-power-law-fluid-in-eccentric-NwwIysazWk
Publisher
Elsevier
Copyright
Copyright © 2016 Elsevier B.V.
ISSN
0920-4105
eISSN
1873-4715
D.O.I.
10.1016/j.petrol.2016.05.038
Publisher site
See Article on Publisher Site

Abstract

Axial movement of drillstring during drilling operations causes downhole pressure variations, which are commonly known as surge and swab pressures. This paper presents a new eccentric annulus surge pressure (EASP) model for yield power law (YPL) fluid. To develop the model, flow in eccentric annulus was investigated using computational fluid dynamics (CFD) technique (ANSYS Fluent). CFD simulations were conducted varying fluid rheological parameters, tripping speed and annular geometry. Simulation results are analyzed considering surge pressure ratio (i.e. ratio of surge pressure in eccentric annulus to that of concentric annulus) as a parameter for quantifying effect of eccentricity on surge pressure. Surge pressure ratio (SPR) is found to be very sensitive to fluid behavior index and annular eccentricity and diameter ratio. In addition to the CFD studies, small-scale laboratory experiments were conducted to validate accuracy of the EASP model. Results show that the model accurately (i.e. maximum error of ±5%) and conveniently predicts surge and swab pressures for YPL (Herschel Buckley) fluid in eccentric annulus without requiring complex numerical procedures. The model is valid for wide ranges of diameter ratio (0.2≤Kd≤ 0.8), eccentricity (0≤ ε≤0.9) and fluid behavior index (0.2≤n≤ 1).

Journal

Journal of Petroleum Science and EngineeringElsevier

Published: Sep 1, 2016

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off