1. What is Fan CFM?

CFM (Cubic Feet per Minute) measures the volume of air a fan can move per minute. It's a crucial specification for determining a fan's performance and suitability for specific applications.

2. How Does the Calculator Work?

The calculator uses the CFM equation:

Where:

• \( rpm \) — Rotations per minute of the fan
• \( displacement \) — Volume of air moved per revolution (in cubic feet)
• \( efficiency \) — Fan efficiency as a fraction (typically 0.7-0.9)

Explanation: The equation calculates the theoretical air volume moved, adjusted by the fan's efficiency.

3. Importance of CFM Calculation

Details: Proper CFM calculation ensures adequate ventilation for spaces, cooling for equipment, and efficient system design.

4. Using the Calculator

Tips: Enter fan RPM, displacement per revolution in cubic feet, and efficiency (default is 0.85). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a good CFM for a room fan?
A: For home use, 1000-3000 CFM is common. Larger spaces or industrial applications may require 5000+ CFM.

Q2: How does fan blade design affect CFM?
A: Blade pitch, number of blades, and shape significantly impact both displacement and efficiency.

Q3: What's typical fan efficiency?
A: Most fans are 70-90% efficient. High-performance fans may reach 92-95% efficiency.

Q4: How does static pressure affect CFM?
A: Higher static pressure reduces actual CFM. This calculator provides theoretical maximum CFM at zero pressure.

Q5: Can I use this for HVAC system calculations?
A: Yes, but account for duct resistance and system losses in final design.