1. What Is Air Flow Rate?

Air flow rate (Q) is the volume of air that passes through a given cross-sectional area per unit time. It is a fundamental parameter in HVAC systems, ventilation design, and fluid dynamics calculations.

2. How Does The Calculator Work?

The calculator uses the basic air flow rate formula:

Where:

• \( Q \) — Air flow rate (m³/s or CFM)
• \( A \) — Cross-sectional area (m²)
• \( v \) — Air velocity (m/s)

Explanation: The formula calculates the volumetric flow rate by multiplying the cross-sectional area through which air flows by the average velocity of the air.

3. Importance Of Air Flow Rate Calculation

Details: Accurate air flow rate calculation is essential for designing ventilation systems, determining HVAC requirements, ensuring proper air quality in buildings, and optimizing industrial processes involving air movement.

4. Using The Calculator

Tips: Enter cross-sectional area in square meters, air velocity in meters per second, and select your preferred output unit (m³/s or CFM). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What Is The Difference Between m³/s And CFM?
A: m³/s (cubic meters per second) is the SI unit for volumetric flow rate, while CFM (cubic feet per minute) is the imperial unit commonly used in North America. 1 m³/s = 2118.88 CFM.

Q2: How Do I Measure Cross-sectional Area?
A: For circular ducts, use A = π × (diameter/2)². For rectangular ducts, use A = width × height. Ensure consistent units (meters for SI calculations).

Q3: What Is A Typical Air Velocity Range?
A: In HVAC systems, typical air velocities range from 2-5 m/s (400-1000 fpm) in ducts, but this varies based on application and duct size.

Q4: When Should I Use This Calculation?
A: Use for ventilation system design, HVAC sizing, industrial exhaust systems, cleanroom air flow requirements, and any application involving air movement through defined pathways.

Q5: Are There Limitations To This Formula?
A: This assumes uniform velocity profile and incompressible flow. For highly turbulent flow, compressible flow, or non-uniform velocity distributions, more complex calculations may be needed.