1. What is FPM to CFM Conversion?

The FPM to CFM conversion calculates airflow volume from velocity and cross-sectional area. CFM (Cubic Feet per Minute) measures volumetric flow rate, while FPM (Feet per Minute) measures linear velocity.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( CFM \) — Cubic Feet per Minute (flow rate)
• \( FPM \) — Feet per Minute (velocity)
• \( A \) — Area in square feet (cross-sectional area)

Explanation: This formula converts linear air velocity to volumetric flow rate by multiplying velocity by the cross-sectional area through which air is flowing.

3. Importance of CFM Calculation

Details: CFM calculation is essential for HVAC system design, ventilation planning, industrial airflow management, and ensuring proper air exchange rates in buildings and industrial processes.

4. Using the Calculator

Tips: Enter velocity in feet per minute and area in square feet. Both values must be positive numbers. The calculator will compute the corresponding CFM value.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between FPM and CFM?
A: FPM measures how fast air is moving (velocity), while CFM measures how much air is moving (volume per minute).

Q2: Where is this conversion commonly used?
A: HVAC system design, ductwork sizing, ventilation systems, industrial exhaust systems, and air handling unit specifications.

Q3: How do I measure the area for duct calculations?
A: For rectangular ducts: width × height. For circular ducts: π × (radius)². All measurements in feet.

Q4: What are typical FPM values in HVAC systems?
A: Typically 600-900 FPM for main ducts, 400-600 FPM for branch ducts, and 300-500 FPM for final runs.

Q5: Can I use this for liquid flow calculations?
A: The principle is the same, but units would change (e.g., GPM instead of CFM for gallons per minute).