Darcys Law Calculator

Darcys Law Calculator can be used to calculate the flow velocity in porous media based on flow rate, cross-sectional area, hydraulic gradient, and permeability.

Input Parameters

Calculation Results

Calculation Formula

v = (Q / A) / (hL/L) = k * (hL/L)

Where:
v = Flow Velocity [L/T]
Q = Flow Rate [L³/T]
A = Cross-sectional Area [L²]
hL/L = Hydraulic Gradient [dimensionless]
k = Permeability [L²]

Darcys Law Calculator Usage Guide

Learn how to use the Darcys Law Calculator and its working principles

What is Darcys Law?

Darcys Law describes the flow of fluid through a porous medium. It states that the discharge rate per unit cross-sectional area is proportional to the hydraulic gradient and the intrinsic permeability of the medium.

How to Use This Calculator

  1. Enter the Flow Rate (Q) in the appropriate units (e.g., cubic meters per second).
  2. Enter the Cross-sectional Area (A) through which the fluid flows (e.g., square meters).
  3. Enter the Hydraulic Gradient (hL/L), which is the change in hydraulic head per unit length.
  4. Enter the Permeability (k) of the medium (e.g., meters squared).
  5. Click the Calculate button to compute the flow velocity.

Applications

Darcys Law is widely used in hydrogeology, soil mechanics, and environmental engineering to:

  • Design water supply systems and drainage
  • Assess contaminant transport in groundwater
  • Understand soil erosion and irrigation efficiency

Example Calculation

If a pipe with a cross-sectional area of 0.1 m² has a flow rate of 0.02 m³/s and a hydraulic gradient of 0.05, with a permeability of 1.2 × 10⁻⁴ m², the flow velocity would be:

v = (0.02 m³/s / 0.1 m²) / 0.05 = 4 m/s