OESI Zonal Isolation R&D Effort

OESI Webcast, 24 February, 2017

Eric van Oort & Saeid EnayatpourUT Austin

Slide 1

AgendaOESI Zonal Isolation R & D Effort Update

• Introduction– Importance of cementing/ZI R&D– Focus on displacement & cement placement

• Overview of Prior Work– Current state-of-the-art in open literature– New SPE paper

• R&D Progress– Modeling work– Timeline and deliverables

• Q & A Session

© Dr. Eric van Oort

Slide 2

Eric van Oort Saeid Enayatpour

Slide 3

Industry Effort after Macondo

Reactive• Blowout recovery focus

– Human factors/situational awareness during incidents

– BOP operation during blowout– Spill prevention– Spill recovery– Incident command, sharing of

information– Well capping– Relief well planning & execution– Etc.

Proactive• Blowout prevention focus

– Human factors/situational awareness to prevent incidents

– Active RTM and verification of barriers

– SEMS– Cementing and zonal isolation

improvement– Interpretation of positive /

negative production casing tests– Etc.

Industry efforts to date seem to have gravitated to being reactive, rather than proactive – but the focus is shifting!

Slide 5

© Dr. Eric van Oort

BSEE Database on Offshore Blowouts

SPE 170323-MS • Improved Regulatory Oversight using Real-Time Data Monitoring Technologies in the Wake of Macondo • Kyle M. Carter & Eric van Oort

(From Booth, 2010)

Drilling Event

Formation Strength

Drilling Event

Drilling Event

Casing & Cement

Casing & Cement

BOP Reliability

Drilling Event Detection

Casing & Cement EvaluationBOP Reliability Verification

Formation Strength Evaluation

Slide 6

© Dr. Eric van Oort

Cementing is evidently the lead cause of offshore blowouts

DW Well Design EvolutionNormal Clearance Well Tight Clearance Wells

Slide 7

Adopted from API RP 96, courtesy John Gradishar

© Dr. Eric van Oort

Mars B – Olympus Well Design

Picture adopted from OTC 25437

Picture adopted from SPE 170977

Work by van der Haak, Grant, Japar and Reagins - Shell

Slide 8

© Dr. Eric van Oort

Mars B –Olympus Well

Design

Picture adopted from OTC 25437

Work by van der Haak, Grant, Japar and Reagins - Shell

Slide 9

© Dr. Eric van Oort

• Wellbore integrity - no flows /no losses / no instability

• Wellbore deviation• Wellbore quality / uniformity• Annular clearances• Casing centralization • Flow rate • Mud-spacer rheological relationship• Cement-spacer rheological relationship• Cement volume - contact time • Pipe movement (rotation/reciprocation)

What is Important in Cementing?Cementing is 80-90% a (dis)placement problem and 10-20% a chemistry problem

Chemistry

Placement

• Cement-formation-pipe material property (bonding) relationship

• Cement material properties

10

Slide 10

© Dr. Eric van Oort

85% Displacement!

15% Chemistry

OESI Effort: Cement Displacement Modeling1. Few displacement models readily available for job design / evaluation

o Usually proprietary / black boxo Usually company exclusive

2. Cement displacement is a very complex problemo Must account for drilling fluid, spacer(s), cement (lead, tail)o Must account for contrast in density, viscosity, polarity, etc. between fluidso Must properly reflect non-Newtonian viscosity (3-parameter model such as YPL)o Must account for pumping schedule, rates, laminar vs. turbulence, contact timeo Must account for well trajectory (depth, deviation, azimuth, tortuosity)o Must account for casing characteristics (connections, floats, shoe track, etc.)o Must be able to simulate pipe eccentricity o Must be able to simulate casing movement, i.e. rotation / reciprocationo Etc.

3. Modeling requires sophisticated software (which we have: ANSYS FLUENT) 4. Modeling requires relevant expertise (which we have: Dr. Saeid

Enayatpour)

11

Slide 11

© Dr. Eric van Oort

Prior Work - Overview• OTC 18513 – Savery, Darbe & Chin – Halliburton – 2007

– Modeling Fluid Interfaces During Cementing Using a 3D Displacement Simulator

• SPE 124726 – Moroni et al., Halliburton, 2009– Pipe rotation Improved Hole Cleaning and Cement-Slurry Placement: Mathematical

Modeling and field Validation

• SPE/IADC 166799 – Edwards et al. – Shell/Halliburton – 2013– Prediction of Residual Cement in Drillpipe after Balanced-Plug Job using Finite

Difference 3D Displacement Simulator

• IADC/SPE 167922 – Chen et al. – Baker Hughes – 2014– Intermixing of Cementing Fluids: Understanding Mud Displacement and Cement

Placement

• SPE 177612 – Godoy et al. – Statoil / Oxand – 2015– Well Integrity Support by Extending Cement Evaluation – Numerical Modeling of

Primary Cement Jobs

Slide 12

© Dr. Eric van Oort

Previous Work on Fluid DisplacementA number of studies have been carried out on fluid displacement in pipes. The main issues observed in most of these studies are as follows:• Many simplifying assumptions are made which get the

numerical results far from field condition• Combined physics of the model complexity such as pipe

geometry, eccentricity, etc. with non-Newtonian rheology are barely used in the context of a finite element tool

• Computational requirements are intensive (excessive)• Model/software is proprietary / not readily accessible

Slide 13

© Dr. Eric van Oort

Progress by OESI / UT Austin• ANSYS Model validation work

– Numerical model compared to analytical solutions

• Concentric and eccentric pipe scenario’s

• Two-phase immiscible flow– Mud / spacer or mud / cement

displacement• Newtonian and YPL fluid models

– Most drilling / cementing fluids follow YPL model

• Effect of pipe rotation• No simplifying assumptions in

solving the N-S equations!

Slide 14

© Dr. Eric van OortSPE 184702 – SPE/IADC Drilling Conference 2017

Feb. 2016: Validation WorkSlide 15

© Dr. Eric van Oort

Figure 12 – Three instances at sequential times of interface locations and conditions in a two-phase immiscible YPL fluid displacement.

Deepwater Intermediate String Calculations

Slide 16

13 5/8” Casing in 16.5” hole

Cement Displacement Video

Effect on Hydraulic Pressure / ECD

Slide 18

© Dr. Eric van Oort

Hydraulic pressure reduces with increasing pipe eccentricity, lowering ECD

Effect of Pipe Rotation - 1

19

Slide 19

© Dr. Eric van Oort

Effect of Pipe Rotation - 2

Slide 20

Combined Effect of Eccentricity & Pipe Rotation

21

Slide 21

Quiz: what are the possible implications of the results in these two graphs?

Timeline & Deliverables

22

Slide 22

© Dr. Eric van Oort

Milestone

Invitation to AC members (deepwater operators in particular) to work with us to simulate field cases, particularly deepwater production casing cementations!

Q & A

Slide 23

© Dr. Eric van Oort