Design and Engineering Forum
[Home] [Design Resources]
[ POSTING POLICY / RULES ][Archive#1] [Archive #2] [Archive #3] [Calculators]

duct design
Post Reply   Forum
Posted by: constrictor

10/12/2004, 19:32:27

Author Profile Mail author Edit

hello there, im new to this forum. I would like to ask anyone who has the knowledge in duct design. Here are some of my questions.

1) how do you compute static pressure?

2) how do you compute the losses of air volume on a duct run?

3) Do you know any site which teaches you techniques for a good duct design?

Thanks guys!







Post Reply | Recommend | Alert Rate View All   | |

Replies to this message


Re: duct friction
Re: duct design -- constrictor Post Reply Top of thread Forum
Posted by: vsenbe2000

10/13/2004, 04:24:48

Author Profile Mail author Edit

Duct Friction Calculation Formula

A duct friction - major loss - calculation formula of rectangular and circular ducts

Circular Ducts

Major loss - friction - in circular ducts may be expressed as: 

Pd = (0.109136  q1.9) / d5.02        (1)

where 

Pd = friction (head or pressure loss) (inches water gauge/100 ft of duct) 

d = equivalent duct diameter (inches)

q = air volume flow - (CFM - Cubic Feet per Minute)

Rectangular Ducts

For rectangular ducts the diameter - d - may be calculated as: 

d = 1.30 x ((a x b)0.625) / (a + b)0.25)       (1)

where 

a = length of one side (inches)

b = length of the other side (inches)







Post Reply | Recommend | Alert Rate Where am I? Original Top of thread

Powered by Engineers Edge

© Copyright 2000 - 2018, by Engineers Edge, LLC All rights reserved.  Disclaimer