HVAC Air Duct Sizing Calculator | Muhendis Portal

Calculate circular and rectangular air duct dimensions, airflow velocity (m/s) and pressure drop (Pa/m) using the equal friction method.

Verified Engineering Calculation Engine

Engineered for mechanical, HVAC, piping, and design engineers in compliance with international standards (ISO, DIN, EN, ASME, ASHRAE). Load the interactive tool for real-time calculations and automated reports.

Frequently Asked Questions (FAQ)

What is the equal friction method in duct sizing?

It sizes all duct branches maintaining a constant pressure loss per unit length (typically 0.8 to 1.0 Pa/m in comfort systems), simplifying hydraulic balance.