MULTIPHASE HYDRAULICS

Mixed-Phase Line Sizing Tool

Workbook-based mixed-phase screening tool implementing the supplied Excel logic for homogeneous sizing, superficial velocities, horizontal two-phase pressure-drop correlations and Beggs & Brill inclined/vertical pressure drop.

Beggs & BrillFriedelChisholm-BaroczyLockhart-Martinelli

All Calculators

Input Parameters

Calculation Basis

Horizontal correlation selection

Horizontal mode is limited to Friedel, Chisholm-Baroczy and Lockhart-Martinelli pressure-drop correlations.

Service & Sizing Criteria

Service Type

Industry best practice mixed-phase ρV² and Mach screening check

Sizing Basis

Service limit, utilization and remarks are shown in the Service Limit Check card.

Mach / Acoustic Velocity Basis

Acoustic velocity / speed of sound (m/s)

Use project flare package or fluid model value at flowing conditions.

Pipe Data

NPS

Schedule

Pipe ID (mm)

Must be > 0

Pipe Length (m)

Must be > 0

Roughness (mm)

Must be >= 0

Fittings / Minor Losses

Fitting Type

Quantity

Item	Qty	K/item	ΣK	Remove
Total ΣK			0.000

Minor-loss screening uses homogeneous/no-slip density and mixture velocity: ΔP_K = ΣK × ρ_NS × v_m² / 2. Final mixed-phase fitting losses require project/vendor data or approved multiphase software.

Flow Rates

Water flow (kg/h)

HC liquid flow (kg/h)

Gas flow (kg/h)

At least one liquid flow and gas flow are required for mixed-phase sizing.

Fluid Properties

Water density (kg/m3)

HC liquid density (kg/m3)

Gas density (kg/m3)

Water viscosity (cP)

HC liquid viscosity (cP)

Gas viscosity (cP)

Surface tension (N/m)

Converted internally to dynes/cm for workbook correlations.

Enter mixed-phase data and click Calculate.

Methodology & Assumptions

Workbook Basis

Mixed liquid density follows the workbook mass-fraction reciprocal density basis; mixed liquid viscosity uses volumetric arithmetic blending to match the Excel workbook.
Horizontal pressure-drop equations follow the workbook implementations for Friedel, Chisholm-Baroczy and Lockhart-Martinelli, including workbook unit conversions and friction-factor switches. Correlation selection is manual in this web version.
Inclined/vertical mode uses Beggs & Brill flow regime map, holdup correction, no-slip Reynolds number, friction-factor ratio, length-scaled hydrostatic head and acceleration correction reference value. The hydrostatic term is length-scaled as ρTP·L·sinθ/144 in English units; acceleration correction remains a separate reference value.

Limitations

Screening-level tool. Not a substitute for OLGA, LedaFlow, Pipesim, HYSYS/UniSim hydraulics, or project multiphase model validation.
Input gas density must be provided at flowing pressure and temperature. No pressure-dependent gas expansion, flashing, condensation, slug tracking or terrain profile is calculated.
Horizontal pressure-drop correlations are empirical; validate selected correlation against project practice and fluid envelope.
Beggs & Brill is a steady-state empirical method; vertical/sloped results are sensitive to holdup and inclination.
Mixed-phase sizing check compares calculated homogeneous momentum, ρ_NSv_m², against the selected project line-sizing service criterion.
Mach number is calculated from v/a. Acoustic velocity can be entered manually or estimated with the Newton-Laplace ideal-gas relation a = √(kP/ρg). The estimate is for screening only; project-approved flare hydraulics or fluid-package acoustic velocity should govern final design.