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HVAC MEP Engineering Tool

HVAC Air Duct Sizing & Friction Loss Calculator

Calculate equivalent rectangular and round duct shapes, air velocities, and pressure drops instantly using engineering standard flow physics.

Input parameters (Parameters)

MEP Configurator
2. Design air volume (Airflow Q)1500 m³/h
m³/h
CFM
3. Duct Dimensions
Diameter D300 mm

Calculation results (Flow Physics Report)

Velocity
5.89 m/s

Limit reference value: < 6 m/s

Unit friction resistance (Head Loss)
1.372 Pa/m

Recommended upper limit: 1.0 Pa/m

Equivalent hydraulic diameter (Hydraulic Diam.)
300 mm

Cross-sectional area: 0.0707

Duct physical airflow section preview (Dynamic Flow Visualizer)Re = 117632

* The animation shows the flow velocity simulation of the air flow line in the center of the air duct. The flow line changes from blue to red, indicating that the pressure loss in the pipe is increasing. (Red is the high loss area). Use Haaland Equations and Colebrook Pipe Resistance Fluid Dynamics for accurate solution.