Two-Phase Flow Regime Predictor

Predict microfluidic flow regimes by calculating capillary and Weber numbers

Input Parameters

Continuous Phase Velocity (m/s)

Dispersed Phase Velocity (m/s)

Continuous Phase Viscosity (Pa·s)

Dispersed Phase Viscosity (Pa·s)

Interfacial Tension (N/m)

Channel Width (µm)

Calculated Values

Capillary Number (Ca)

0.0167

Weber Number (We)

0.8333

Predicted Flow Regime

Flow Regime

Dripping

Droplet formation with necking. Good droplet control and uniformity.

Flow Pattern Visualization

Squeezing

Ca < 0.01

Dripping

0.01 < Ca < 0.3

Jetting

Ca > 0.3

About This Tool

Capillary Number (Ca)

Ca = μU/γ describes the ratio of viscous to surface tension forces. Low Ca values indicate surface tension dominates, promoting droplet formation.

Weber Number (We)

We = ρU²d/γ describes the ratio of inertial to surface tension forces. It helps predict the transition from droplet to jetting regimes.

Flow Regimes

Squeezing: Pressure-driven breakup, highly monodisperse
Dripping: Gravity/capillary-driven, good droplet control
Jetting: High velocity jets, smaller final droplet size

Disclaimer: Flow regime boundaries are approximate and based on published empirical data. Actual transitions depend on channel geometry, surface wettability, surfactant chemistry, and fluid properties. Always validate with experimental observation.