Darcy (D)
Permeability that lets 1 cm³/s of a 1 cP fluid pass through 1 cm² under a pressure gradient of 1 atm/cm: about 9.869233 × 10⁻¹³ m².
What is a darcy?
- Symbol
- D
- Quantity
- Permeability (Porous Media)
- Unit system
- other
- Definition
- Permeability that lets 1 cm³/s of a 1 cP fluid pass through 1 cm² under a pressure gradient of 1 atm/cm: about 9.869233 × 10⁻¹³ m².
- Exact
- Yes, the value is exact by definition
- Source
- NIST Special Publication 811 (2008), Appendix B.8
Common applications
Used in petroleum engineering, hydrogeology and filtration for the permeability of rock, sand and filters.
Darcy in other permeability (porous media) units
- 1 D ≈ 9.869232667e-13 m² (k)Darcy to Square meter (permeability) converter
- 1 D ≈ 0.9869232667 µm²Darcy to Square micrometer converter
- 1 D = 1000 mDDarcy to Millidarcy converter
Darcy quick reference
| Darcy | Square meter (permeability) | Square micrometer | Millidarcy |
|---|---|---|---|
| 1 D | ≈ 9.869232667e-13 m² (k) | ≈ 0.9869232667 µm² | = 1000 mD |
| 10 D | ≈ 9.869232667e-12 m² (k) | ≈ 9.869232667 µm² | = 10000 mD |
| 100 D | ≈ 9.869232667e-11 m² (k) | ≈ 98.69232667 µm² | = 100000 mD |
| 1000 D | ≈ 9.869232667e-10 m² (k) | ≈ 986.9232667 µm² | = 1000000 mD |
Where the darcy fits
The next smaller permeability (porous media) unit is the millidarcy (mD). 1 D = 1000 mD, and 1 mD = 0.001 D.
The next larger permeability (porous media) unit is the square micrometer (µm²). 1 D ≈ 0.9869232667 µm², and 1 µm² = 1.01325 D.
Frequently asked questions
- How many square meters (permeability) are in one darcy?
- One darcy ≈ 9.869232667e-13 m² (k) (square meters (permeability)).
- How many square micrometers are in one darcy?
- One darcy ≈ 0.9869232667 µm² (square micrometers).
- How many millidarcies are in one darcy?
- One darcy = 1000 mD (millidarcies).