APPLICATION OF MULTI-SEGMENTED WELL MODULE IN HORIZONTAL WELL

Elisabeth Maria WawolumayaReservoir EngineerSoftware Integrated Solutions

Objectives To deliver the concept and effect of Multi-segmented Well model in horizontal well

compared to Standard Well Model.

Background Horizontal wells provide significant benefits and are becoming a preferred option in

many cases. Several types of well models in ECLIPSE (e.g: Standard Well, Multi-segmented

Well) Concerns about the loss of productivity in horizontal well due to water coning.

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Outline

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INTRODUCTION TO ECLIPSE WELL MODEL

What is a well model?

The flow in the wellbore itself is modeled in two stages:1)Well connections to Reference depth2)Reference depth to Surface – VFP table

BHP @ Ref. depth

Pwh @ Surface

Grid block to grid block

Grid block to well connection

Well connection to reference depth

Reference depth to surface Well model

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Fluid Traveling from Reservoir to Surface

1

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Pressure at reference depth is calculated to satisfy the well constraints (prod rate target)

ECLIPSE Well Models

Well connections to Reference depth (BHP)

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1

22

Reference depth (BHP) to Surface

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Flow Equations

qp,1

qp,2

qp,n

qp,tot

Total flow at surface = sum of flows at each connection:qp,tot = qp,1 + qp,2 + … + qp,n

SrrB

pppkhkq

woipip

ibhpipirpip

/ln

2

,,

,,,

ibhpioipiip pppMTq ,,,

TransmissibilityTransmissibility MobilityMobility Pressure DropPressure Drop

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SrrKhc

Two

j

/ln

igig

irgig B

kM

,,

,,

3 solution variablesPBHP, Fwater, Fgas

PotentialDifferencePotentialDifference

Pressure Drop

In standard well model, phydr >>> pfrict & pacc

ptot = phyd = gh

ptot = pfriction + pacceleration + phydrostatic

Hydrostaticcorrectionfrom BHPdatum toconnection

Cell to w

ell

drawdown

Frictional pressure drop andAcceleration pressure drop

Pthp at Tubing

HeadPump or

compressor

Hydrostaticcorrectionfrom BHPdatum toVFP datum

Well connections to Reference depth

ibhpioipiip pppMTq ,,,

Reference depth to Surface (VFP table)

BHP ref. depth

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?

ptot = phyd = ghphydr >>> pfrict & pacc

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Horizontal wells often have frictional pressure loss

Multi-segmented Well Model Specifically designed for horizontal and multilateral wells. Detailed description of fluid flow Dividing wellbore into a number of segments Each segment has its own set of independent variables to describe the local fluid

conditions.

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MSW Application: Horizontal Well

PP

PPtoetoe

PPheelheelPP

PPrr

PP

PPrrPP

PPrr

AccelerationAccelerationFrictionFriction

f Fanning friction factorL lengthD Tubing IDρ fluid densityv fluid velocity

C unit conversion constantw mass flow rate of the fluid mixture through the segmentedA segmenteds area of cross-section for flow

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HydrostaticHydrostatic

PETREL DEMO PROJECT

1. Model Description

Phase: Dry gas & Water Porosity = 0.25 High permeability (x, y, z direction) = 3,000 mD Perforation Length (horizontal section) = 2,000 m

GWC

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Fine Gridi, j increment = 50 mk increment = 10 m

X max = 10,000 mY max = 10,000 mThickness = 1,000 m

Fine Gridi, j increment = 50 mk increment = 10 m

X max = 10,000 mY max = 10,000 mThickness = 1,000 m

2. Completion Design & Development Strategy

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The well is completed in 21 grid blocks (2 km length)

Well production controlGas rate target = 5E8 sm3/dayBHP limit = 10 bar

3. Defining MSW

1 2

3Phase slip√ Drift Flux Model

Allows slip between phases

□ Homogenous flow model

All phases flow with the same velocity

Segment up to- Default top connection / device

in the well- Above the top segment VFP

table- BHP reference depth

Segment per cellEnsures each fluid entry to perforations is modeled separately.

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Segment numeration

Segment up to

14

BHPreference depth

SegmentNumber

BranchNumber

4. Inserting segmentation set to the simulation model

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SIMULATION RESULTS

Results (Fine Grid, High K)

Standard Well

MSW

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Gas Rate Target = 500MM sm3/d

BHP Limit = 10 bar

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Standard Well

MSW

Reservoir grid block pressureBottom hole pressure

Total Pressure Drop Pfrict + Pacc + Phydr

segmented No. 2

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Pfrict

Pacc

Phydr

segmented No. 3 - 21

Year 2014 – 2019 (Standard Well case)

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Year 2014 – 2019 (MSW case)

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Summary

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Multi-segmented Well Model will optimize flow profile along the well bore, especially in horizontal and also multilateral well.

Values

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THANK YOU