Radius Of Well Given Discharge In Confined Aquifer Calculator

Formula Used:

\[ r = \frac{R_w}{\exp\left(\frac{2\pi K_{WH} b_p (H_i - h_w)}{Q_0}\right)} \]

Radius of Influence (R_w):

Coefficient of Permeability (K_WH):

m/s

Aquifer Thickness During Pumping (b_p):

Initial Aquifer Thickness (H_i):

Depth of Water (h_w):

Discharge at Time t=0 (Q_0):

m³/s

Radius of Well (r):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Radius of Well Calculation?

The radius of well calculation determines the distance from the center of a well to its outer boundary based on various hydrogeological parameters. This is essential for understanding well performance and aquifer characteristics in confined aquifer systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ r = \frac{R_w}{\exp\left(\frac{2\pi K_{WH} b_p (H_i - h_w)}{Q_0}\right)} \]

Where:

\( r \) — Radius of well (m)
\( R_w \) — Radius of influence (m)
\( K_{WH} \) — Coefficient of permeability in well hydraulics (m/s)
\( b_p \) — Aquifer thickness during pumping (m)
\( H_i \) — Initial aquifer thickness (m)
\( h_w \) — Depth of water (m)
\( Q_0 \) — Discharge at time t=0 (m³/s)
\( \pi \) — Mathematical constant pi (approximately 3.1416)

Explanation: This formula calculates the well radius based on the exponential relationship between various aquifer parameters and discharge rate.

3. Importance of Well Radius Calculation

Details: Accurate well radius calculation is crucial for well design, determining well efficiency, assessing aquifer characteristics, and planning groundwater extraction projects in confined aquifers.

4. Using the Calculator

Tips: Enter all values in appropriate units (meters for lengths, m/s for permeability, m³/s for discharge). All values must be positive and valid for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: What is a confined aquifer?
A: A confined aquifer is an aquifer that is bounded above and below by impermeable layers, creating pressure conditions that affect water flow.

Q2: How does coefficient of permeability affect the calculation?
A: Higher permeability values generally result in smaller calculated well radii, as water can flow more easily through the aquifer material.

Q3: What is radius of influence?
A: Radius of influence is the distance from the well center to the point where the drawdown curve meets the original water table.

Q4: When is this calculation most applicable?
A: This calculation is specifically designed for confined aquifers with steady-state flow conditions and homogeneous aquifer properties.

Q5: What are typical values for well radius?
A: Well radii typically range from 0.1 to 1.0 meters, depending on the well construction and aquifer characteristics.