Fan Calculator

Calculate the airflow (CFM) of a fan based on its speed and diameter

Input Parameters

Calculation Results

Calculation Formula

CFM = π × (D²/4) × V

Where:
CFM = Cubic Feet per Minute
π = Pi (approximately 3.14159)
D = Fan Diameter (in feet)
V = Fan Speed (feet per minute)

Results

CFM (Cubic Feet per Minute): 0

Flow Velocity (feet per minute): 0

Fan Calculator Calculator Usage Guide

Learn how to use the Fan Calculator calculator and its working principles

How to Use the Fan Calculator

  1. Enter the Fan Diameter in inches. This is the diameter of the fan blades.
  2. Enter the Fan Speed in RPM (Revolutions Per Minute). This is how fast the fan is spinning.
  3. Optionally, enter the Air Density in lb/ft³. The default value is 0.075 lb/ft³ (standard air density at sea level).
  4. Click the Calculate button to compute the CFM and flow velocity.
  5. Click the Reset button to clear all inputs and results.

Understanding the Results

The calculator provides two key results:

  • CFM (Cubic Feet per Minute): This measures how much air the fan moves per minute. Higher CFM means more air movement, which is useful for cooling, heating, or ventilation applications.
  • Flow Velocity (feet per minute): This measures how fast the air is moving past a point near the fan. It helps in understanding the fan's performance characteristics.

Formula Explanation

The calculator uses the following formula to calculate CFM:

CFM = π × (D²/4) × V

Where:

  • π is the mathematical constant Pi (approximately 3.14159)
  • D is the fan diameter in feet
  • V is the flow velocity in feet per minute

Practical Applications

This calculator is useful for:

  • Designing ventilation systems
  • Choosing the right fan for cooling electronic devices
  • Calculating air movement in HVAC (Heating, Ventilation, and Air Conditioning) systems
  • Understanding fan performance in various applications