Coefficient Of Permeability Given Aquifer Loss Coefficient Calculator

Formula Used:

\[ k = \frac{\ln\left(\frac{R}{r'}\right)}{2\pi B b_w} \]

Radius of Influence (R):

Radius of Well (r'):

Aquifer Loss Coefficient (B):

Aquifer Thickness (b_w):

Coefficient of Permeability (k):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Coefficient of Permeability?

The Coefficient of Permeability of soil describes how easily a liquid will move through the soil. It is a key parameter in hydrogeology and environmental engineering for understanding groundwater flow and contaminant transport.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ k = \frac{\ln\left(\frac{R}{r'}\right)}{2\pi B b_w} \]

Where:

\( k \) — Coefficient of Permeability (m/s)
\( R \) — Radius of Influence (m)
\( r' \) — Radius of Well (m)
\( B \) — Aquifer Loss Coefficient
\( b_w \) — Aquifer Thickness (m)
\( \pi \) — Archimedes' constant (≈3.14159)
\( e \) — Napier's constant (≈2.71828)

Explanation: This formula calculates the permeability coefficient based on well geometry and aquifer characteristics, using natural logarithm for the ratio of influence radius to well radius.

3. Importance of Permeability Calculation

Details: Accurate permeability estimation is crucial for designing groundwater extraction systems, predicting contaminant migration, and assessing aquifer productivity for water supply projects.

4. Using the Calculator

Tips: Enter all values in appropriate units (meters for lengths). Ensure all values are positive and valid (R > r', B > 0, b_w > 0) for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range of permeability coefficients?
A: Permeability varies widely from 10⁻¹² m/s for clay to 10⁻² m/s for gravel, depending on soil type and composition.

Q2: How is radius of influence determined?
A: Radius of influence is typically measured from pumping tests by observing drawdown distances from the well center to where water table remains unaffected.

Q3: What affects aquifer loss coefficient?
A: Aquifer loss coefficient depends on aquifer properties, well construction, and pumping rate, and is constant for a given flow rate.

Q4: When is this formula most applicable?
A: This formula is particularly useful for confined aquifers with steady-state flow conditions and fully penetrating wells.

Q5: Are there limitations to this equation?
A: The formula assumes homogeneous aquifer properties, radial symmetry, and may be less accurate for complex geological conditions or partially penetrating wells.