1. What is the Friction Factor?

The Darcy friction factor (f) is a dimensionless quantity used in the Darcy-Weisbach equation to calculate pressure loss due to friction in pipes. For laminar flow (Re < 2300), it can be calculated simply as 64 divided by the Reynolds number.

2. How Does the Calculator Work?

The calculator uses the laminar flow friction factor equation:

Where:

• \( f \) — Darcy friction factor (dimensionless)
• \( Re \) — Reynolds number (dimensionless)

Explanation: This equation is valid only for laminar flow (Re < 2300). For turbulent flow, more complex equations like the Colebrook-White equation are needed.

3. Importance of Friction Factor

Details: The friction factor is essential for calculating pressure drops in piping systems, which affects pump sizing, energy requirements, and system design.

4. Using the Calculator

Tips: Enter the Reynolds number (must be > 0). The calculator will return the friction factor for laminar flow conditions.

5. Frequently Asked Questions (FAQ)

Q1: What is the range of validity for this equation?
A: This equation is valid only for laminar flow (Re < 2300). For turbulent flow, different equations must be used.

Q2: What are typical values of the friction factor?
A: For laminar flow, f typically ranges from about 0.01 to 0.1. For turbulent flow, values are generally between 0.01 and 0.05.

Q3: How does pipe roughness affect the friction factor?
A: In laminar flow, pipe roughness has negligible effect. The friction factor depends only on the Reynolds number.

Q4: What if my flow is turbulent?
A: For turbulent flow (Re > 4000), you would need to use the Colebrook-White equation or the Moody chart.

Q5: What are the units of the friction factor?
A: The Darcy friction factor is dimensionless - it has no units.