AIRHEAD: When your measured airflow is ±10 percent of design airflow, you can confidently proclaim that your duct design method works. May 27, 2019 The duct system is one of the most important ...

For the past 50 years, engineers have been “designing” duct systems. Quite often, they were not actually designing the systems, but were sizing duct the duct according to some rule of thumb. The rules ...