Analyze pore size through trusted physical relationships. Switch modes, inspect trends, and save useful outputs. Built for labs, filters, membranes, ceramics, and research work.
| Method | Key Inputs | Estimated Diameter | Comment |
|---|---|---|---|
| Washburn | γ = 0.072 N/m, θ = 0°, ΔP = 180 kPa | 1.60 µm | Good for pressure-based entry estimates. |
| Washburn | γ = 0.048 N/m, θ = 25°, ΔP = 350 kPa | 0.50 µm | Higher pressure lowers the inferred size. |
| Capillary Rise | γ = 0.072 N/m, θ = 0°, ρ = 1000 kg/m³, h = 0.30 m | 97.89 µm | Useful for wetting liquids in capillary channels. |
| Laminar Flow | μ = 1 cP, L = 1 mm, Q = 2 mL/min, ΔP = 10 kPa, n = 1000 | 19.20 µm | Equivalent diameter depends strongly on assumed pore count. |
1. Washburn / Bubble Pointd = (4γ|cosθ|) / ΔP
2. Capillary Rised = (4γ|cosθ|) / (ρgh)
3. Laminar Flow Equivalentd = ((128μLQ) / (πnΔP))^(1/4)
Where d is pore diameter, γ is surface tension, θ is contact angle, ΔP is pressure drop, ρ is density, g is gravity, h is rise height, μ is viscosity, L is thickness, Q is total flow rate, and n is pore count.
It represents an estimated diameter of a pore or capillary-like opening. The value is model-based, so it reflects the chosen test method and assumptions, not a direct microscope image.
Use Washburn when pressure drives entry, capillary rise when liquid height is measured, and laminar flow when you know viscosity, thickness, pressure drop, total flow, and an assumed pore count.
In the pressure-based relation, diameter is inversely proportional to pressure drop. A higher pressure can force liquid or gas through tighter openings, so the inferred pore diameter decreases.
Contact angle strongly affects wetting behavior. A change in angle changes the cosine term, which shifts the computed diameter. Reliable surface chemistry inputs improve reliability.
The flow method returns an equivalent cylindrical diameter. Real pores can be tortuous, irregular, connected, or partially blocked, so image-based sizes and flow-based sizes often differ.
Yes. It is useful for many porous materials, including filters, membranes, sintered parts, foams, and ceramics, as long as the selected method reasonably matches the experiment.
The calculator uses a common pore-size grouping: microporous below 2 nm, mesoporous from 2 to 50 nm, and macroporous above 50 nm. It is a quick interpretation aid.
No. It is a strong screening and teaching tool, but laboratory techniques such as microscopy, mercury intrusion, adsorption analysis, or bubble point testing remain important for validation.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.