Wellbore Genius

Downhole Simulator

Performance modeling

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Boundary conditions

Phase 12 of the formulation. Configure the outer, inner, leak-off, and tip BCs that govern the depletion + fracture solver. All values are stored in field units; consuming panels read this bundle via useBoundaryConditions().

Quick presets

One-click bundles for common scenarios. Each preset replaces the entire active bundle (all four subsections).

Far-field (outer) BC

Boundary applied at r = R_outer. Choose Dirichlet pressure, Dirichlet stress, or no-flow Neumann.

p(R=5000 ft) = 6000 psi

Radius at which the outer BC is enforced.

Wellbore (inner) BC

Sandface coupling at r = r_w. Pick fixed BHP, fixed rate, or shut-in.

BHP = 4000 psi (skin 0)

Hawkins-style mechanical skin.

Leak-off / face BC

Carter leak-off, no-flow face, or pressure-dependent C_L on the fracture face.

C_L = 0.005 ft/√min, S_p = 0.01 gal/ft²
Tip / closure BC

Propagation criterion at the fracture tip — LEFM toughness, fixed tip pressure, or zero-width closure.

K_IC = 1000 psi·√in
BC impact (pre-solver)

Derived quantities computed directly from the active BCs. These are closed-form interpretations — what the depletion / fracture solver will see at t = 0+. (7 derivations)

Far-field

  • Effective outer pressure6,000 psi @ R=5,000 ft

    Dirichlet p — outer ring held at p_initial for all time.

Wellbore

  • Sandface BHP4,000 psi (skin 0.0)

Leak-off

  • Leak-off regimemoderate-leakoff

    C_L = 0.0050 ft/√min · characteristic 1-ft fill time ≈ 10,000 min

  • Spurt loss0.010 gal/ft²

    Instantaneous loss at face contact — consumed at t = 0+.

Tip

  • Tip criterionLEFM, K_IC = 1,000 psi·√in

    intermediate — transition regime

Cross-section

  • Initial drawdown (BHP − p_init)-2,000 psi

    Negative Δp — production (fluid flows from formation to wellbore).

  • R_outer / r_w14,124×

    Effectively infinite-acting near-wellbore.

Active BC bundle: Far-field p(R=5000 ft) = 6000 psi · Wellbore BHP = 4000 psi (skin 0) · Leak-off C_L = 0.005 ft/√min, S_p = 0.01 gal/ft² · Tip K_IC = 1000 psi·√in

Stored in field units (psi, ft, bpm, ft/√min, gal/ft²). Downstream panels will read this bundle via useBoundaryConditions().