1. What is the Darcy Friction Factor?

The Darcy friction factor (f) is a dimensionless quantity used in the Darcy-Weisbach equation to calculate pressure drop due to friction in pipes. For laminar flow (Re < 2300), the friction factor is inversely proportional to the Reynolds number.

2. How Does the Calculator Work?

The calculator uses the laminar flow friction factor formula:

Where:

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

Explanation: This simple relationship is exact for fully developed laminar flow in circular pipes and is derived from the Hagen-Poiseuille equation.

3. Importance of Friction Factor Calculation

Details: Accurate friction factor calculation is essential for determining pressure drops in piping systems, sizing pumps, and designing efficient fluid transport systems in various engineering applications.

4. Using the Calculator

Tips: Enter the Reynolds number (must be > 0). This formula is valid only for laminar flow conditions (Re < 2300).

5. Frequently Asked Questions (FAQ)

Q1: When is this formula applicable?
A: This formula is valid only for laminar flow conditions, typically when Reynolds number is less than 2300.

Q2: What about turbulent flow?
A: For turbulent flow, more complex correlations like the Colebrook-White equation or Moody chart are used to determine the friction factor.

Q3: What are typical friction factor values?
A: For laminar flow, friction factors typically range from about 0.01 to 0.1, decreasing as Reynolds number increases.

Q4: Does pipe roughness affect laminar flow friction?
A: No, in laminar flow, the friction factor is independent of pipe roughness and depends only on the Reynolds number.

Q5: Can this be used for non-circular pipes?
A: For non-circular pipes in laminar flow, the concept of hydraulic diameter is used, and different constants may apply.