1. What is the Darcy-Weisbach Equation?

The Darcy-Weisbach equation calculates the pressure drop due to friction along a given length of pipe with a constant flow rate. It's widely used in fluid mechanics to determine the head loss or pressure drop in pipe systems.

2. How Does the Calculator Work?

The calculator uses the Darcy-Weisbach equation:

Where:

• \( \Delta P \) — Pressure drop (Pa)
• \( f \) — Darcy friction factor (dimensionless)
• \( L \) — Length of pipe (m)
• \( \rho \) — Fluid density (kg/m³)
• \( v \) — Flow velocity (m/s)
• \( D \) — Pipe diameter (m)

Explanation: The equation relates the pressure drop to the pipe geometry, fluid properties, and flow characteristics.

3. Importance of Pressure Drop Calculation

Details: Calculating pressure drop is essential for designing piping systems, selecting appropriate pumps, and ensuring proper flow rates in industrial and domestic applications.

4. Using the Calculator

Tips: Enter all parameters in consistent SI units. The friction factor depends on the flow regime (laminar or turbulent) and pipe roughness.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the friction factor?
A: For laminar flow (Re < 2300), f = 64/Re. For turbulent flow, use Moody chart or Colebrook equation.

Q2: What's the difference between ΔP and head loss?
A: Head loss (h) relates to ΔP through h = ΔP/(ρg), where g is gravitational acceleration.

Q3: Does this work for non-circular pipes?
A: Yes, but use hydraulic diameter (4 × area/perimeter) instead of D.

Q4: What about compressible fluids?
A: This equation is for incompressible flow. For gases, additional considerations are needed.

Q5: How accurate is this calculation?
A: Accuracy depends on correct friction factor and assumption of fully developed flow.