💨 Convective Mass Transfer — Flat Plate & Pipe Calculator

Estimate mass transfer coefficient km, molar flux NA, mass flux, and equivalent diffusion film thickness using Sherwood correlations Sh = f(Re, Sc).

🌊 Boundary Layer Mass Transfer Schematic

📝 Configuration

📐 Geometry & Flow
💧 Fluid & Diffusion Properties
🧪 Concentration Driving Force
Key Equations:

Re = ρuLc/μ, Sc = μ/(ρDAB)

Flat plate laminar average: ShL = 0.664 ReL1/2 Sc1/3
Flat plate turbulent average: ShL = (0.037 ReL0.8 - 871) Sc1/3

Pipe turbulent, Dittus-Boelter mass analogy: Sh = 0.023 Re0.8 Scn

📊 Results & Visualization

Configure inputs and click Calculate to view results.

ℹ️ About Convective Mass Transfer

This calculator estimates convective transport of a dilute species from a surface to a moving fluid using Sherwood-number correlations. It is useful for evaporation, drying, gas absorption, dissolution, and wall-to-fluid species transfer.

📘 Calculation Methodology

Mathematical Model & Theory

The calculator uses the heat/mass transfer analogy: Nusselt-number convection correlations are mapped to Sherwood-number mass transfer correlations by replacing Pr with Sc and thermal diffusivity with mass diffusivity.

Worked Engineering Example

Water vapor over a plate: for air at 25°C, u = 2 m/s, L = 0.5 m, DAB = 2.5×10−5 m²/s, the code calculates Re and Sc, selects the appropriate Sh correlation, then computes km = Sh DAB/L and NA = km(CA,s − CA,∞).

Assumptions & Notes

  • Dilute species A in carrier fluid B.
  • Constant fluid properties and binary diffusivity.
  • Flat-plate correlations assume zero leading-edge concentration boundary layer thickness.
  • Pipe turbulent option uses Dittus-Boelter-style mass analogy; entry effects and reactions are not included.
  • Equivalent film thickness is δm = DAB/km.