Field glossary

System curve

The plot of head the piping demands against flow; it climbs with the square of velocity because friction rises with velocity

Used across 3 Anvilfield field guides, most in HVAC.

Also defined as

The plot of head the piping demands against flow; balancing reshapes it, and the pump runs where its curve crosses it
The duct's square-law plot of pressure required against airflow through that arrangement

Where this shows up