2002 STIM-LAB Proppant Consortium

1
2002STIM-LAB Proppant Consortium

• July 19, 2002
• San Diego, California
• Robert D. Barree
• Michael W. Conway

4.2 - Modeling of Proppant Flowback
2
Original Flowback Model
3
Major Equations

• Normalize velocity to 2 lb/ft 20/40 Lt Wt Ceramic
• Proppant Factor
• Critical velocity 0.65 cm/s PF CF

4
Multiphase Flowback
5
Example of Single Phase Flow Data
6
Flowback Predictive Model

• New modeling approach suggested by
• Bi-power law correlations for sediment transport
  in pressure driven channel flows
• J. Wang, D. D. Joseph Department of Aerospace
  Engineering and Mechanics, University of
  Minnesota, Minneapolis, MN
• M. Conway, R. D. Barree
• Gravity Reynolds number
• Fluid Reynolds number based on particle size

7
Predictive Equation

• In the flowback case, three dimensionless
  parameters d/W, RG , and Rf, enter the power law
  correlation
• This conceptually represents the drag force
  acting on a single particle in a flow field

8
Re-Look at Single Phase Data
9
No Flowback Cases were Identified
10
Effect of Viscosity is Significant
11
Single Phase 20/40 Flowback Results
12
Application of Carreau Model

• Model for proppant size effect
• As approach d/W with no flowback
• Flowback velocity is problematic
• May not show a clear dependence on closure

13
Single Phase 16/30 Flowback Results
14
Single Phase 12/20 Flowback Results
15
Summary of Empirical Diameter Effect
16
Addition of Lower Boundary for Flowback
17
Continuation Program

• Design and execute experiments to clarify key
  parameters required for modeling effort
• Example Minimum velocity for flowback at d/W
  0.01
• Re-examine multiphase data
• Examine multiphase approach
• Use fractional flow
• Relate capillary pressure and saturations to
  additional cohesion and velocity required to
  cause flowback
• Begin to incorporate the effect of resin coated
  proppants