أنشئ حسابًا أو سجّل الدخول للانضمام إلى مجتمعك المهني.
you may use the following :
ASHREA fundamental F.21 Duct Design
SMACNA HVAC Systems Duct Design 4th Edition-2006
ASHREA duct fitting data base program
Elite Duct size program
Mcquay program
relating to duct diameter inch and CFM