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Dukler Two-Phase Flow

Taitel-Dukler Flow Pattern & Pressure Drop for Horizontal Pipelines

Taitel-Dukler Two-Phase Flow Calculator
Predicts flow patterns (stratified, wavy, slug, annular, bubble) and pressure drop in horizontal/near-horizontal two-phase pipelines. Uses Lockhart-Martinelli correlation for pressure drop with API RP 14E erosional velocity checking.

Flow Rates

Pipe Geometry

in
ft
degrees
ft

Liquid Properties

lb/ft³
cp
dyne/cm

Gas Properties

air=1
cp

Operating Conditions

psia
°F

📘 Methodology & References

Calculation Sequence

1. Flow Pattern: Taitel-Dukler (1976) map using Froude numbers and Kelvin-Helmholtz stability
2. Liquid Holdup: Regime-specific correlations (mechanistic for stratified, empirical for slug/annular)
3. Two-Phase Multiplier: Lockhart-Martinelli Φ² = 1 + C/X + 1/X² with regime-dependent C values
4. Pressure Drop: dP/dz = (friction × Φ²) + gravity + acceleration, segmented for compressibility
5. Erosional Check: API RP 14E Ve = C/√ρm where C = 100 for continuous service

Reference Standards

Flow Pattern: Taitel & Dukler, "A Model for Predicting Flow Regime Transitions," AIChE Journal 22(1), 1976
Pressure Drop: Lockhart & Martinelli, Chem. Eng. Progress, 1949
Holdup: Dukler et al., AIChE Journal 10(1), 1964
Erosion: API RP 14E, 5th Edition - Design and Installation of Offshore Production Platform Piping Systems

🌊 Flow Pattern Guide

Stratified (Smooth/Wavy)
Low gas & liquid velocities. Liquid at bottom, gas flows above. Lowest pressure drop. Good for pigging.
Slug/Plug (Intermittent)
Moderate velocities. Liquid slugs alternate with gas pockets. Most problematic - causes separator surging, vibration. Requires slug catcher.
Annular
High gas velocity. Liquid film on pipe wall, gas core with droplets. Higher pressure drop. Common in high-rate gas wells.
Bubble/Dispersed
Very high liquid rate, low gas. Gas bubbles in liquid. Rare in gas pipelines. Behaves like single-phase liquid.

Applicability & Limitations

• Best For: Horizontal and near-horizontal pipes (|angle| ≤ 15°)
• Diameter Range: 2-36 inches (validated)
• Pressure Range: 50-3000 psia
• Accuracy: ±20% for pressure drop, ±15% for holdup (typical)
• Limitation: Not suitable for highly inclined or vertical pipes - use Beggs-Brill instead
• Assumption: Steady-state flow; does not model transient slugging