1. What is Absolute Permeability?

Absolute permeability (k) is a measure of a porous material's ability to allow fluids to pass through it. It's a fundamental property in fields like petroleum engineering, hydrology, and soil science.

2. How Does the Calculator Work?

The calculator uses Darcy's Law for absolute permeability:

Where:

• \( k \) — Absolute permeability (m²)
• \( Q \) — Volumetric flow rate (m³/s)
• \( \mu \) — Fluid viscosity (Pa·s)
• \( L \) — Length of the sample (m)
• \( A \) — Cross-sectional area (m²)
• \( \Delta P \) — Pressure difference (Pa)

Explanation: The equation relates the flow rate through a porous medium to the pressure gradient and the properties of both the fluid and the medium.

3. Importance of Absolute Permeability

Details: Absolute permeability is crucial for determining how easily fluids can move through materials like rock formations, soil, or filters. It's essential for oil and gas production, groundwater studies, and filtration systems.

4. Using the Calculator

Tips: Enter all values in SI units. Ensure all input values are positive numbers. Typical values for permeability range from 10⁻¹² m² (1 millidarcy) for tight rocks to 10⁻⁷ m² for highly permeable materials.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between absolute and relative permeability?
A: Absolute permeability measures flow with a single fluid, while relative permeability describes flow when multiple fluids are present.

Q2: What are typical units for permeability?
A: While the SI unit is m², the oil industry commonly uses darcys (1 Darcy ≈ 0.987×10⁻¹² m²).

Q3: What factors affect permeability?
A: Pore size, connectivity, shape, and tortuosity all influence permeability.

Q4: How does permeability differ from porosity?
A: Porosity measures void space, while permeability measures how easily fluids can flow through that space.

Q5: Can permeability be anisotropic?
A: Yes, many materials (like layered rocks) have different permeability in different directions.