Airflow In Ductwork 7

[@cavelvlan25]

OK

[@muneebahmedshams]

Hi Christopher, i am working on one project to measure the air flow (CFM) the unit have 5 meter long straight duct connected.i am using pitot tube for the task i know all the process but i don't know to measure the correct air flow rate at what distance from the supply fan i should make hole for the pitot tube. Duct area W=270mm H=310 mm