Key Friction Loss Calculator

Key Friction Loss Formula:

\[ \text{Loss} = \frac{K v^2}{2 g} \]

Friction Loss (m):

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1. What is Key Friction Loss?

Definition: Key friction loss (or minor loss) refers to energy loss in fluid flow due to fittings, valves, bends, or other components in a piping system.

Purpose: This calculator helps engineers determine pressure losses in piping systems to ensure proper system design and pump selection.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Loss} = \frac{K v^2}{2 g} \]

Where:

\( \text{Loss} \) — Head loss due to friction (meters)
\( K \) — Loss coefficient (dimensionless)
\( v \) — Flow velocity (meters/second)
\( g \) — Acceleration due to gravity (9.81 m/s²)

Explanation: The loss is proportional to the square of the velocity and the loss coefficient of the fitting.

3. Importance of Friction Loss Calculation

Details: Accurate friction loss calculations are critical for proper pump sizing, system efficiency, and avoiding cavitation or flow issues.

4. Using the Calculator

Tips: Enter the loss coefficient (K) for your fitting, flow velocity, and gravity (default 9.81 m/s²). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Where can I find K values for different fittings?
A: K values are typically found in engineering handbooks or manufacturer specifications for specific fittings.

Q2: How does velocity affect friction loss?
A: Friction loss increases with the square of velocity, so doubling velocity quadruples the friction loss.

Q3: What's a typical K value for a 90° elbow?
A: A standard 90° elbow typically has a K value between 0.3 and 0.9 depending on size and material.

Q4: Does this include major (pipe) friction loss?
A: No, this calculates only minor (local) losses. Major losses require the Darcy-Weisbach equation.

Q5: What units should I use?
A: Use consistent SI units: meters for length, m/s for velocity, and m/s² for gravity.