High Velocity Ductwork Sizing 1

[friartuck]

Hi Folks

I am currently designing a high velocity ductwork system for distribution of air at (you've guessed it..)High Velocity. This is to transport hot air to drum jet or induction diffusers at high level in a warehouse for winter heating. The air might typically be at 30 to 45 degrees celsius.

I have merrily sized standard ductwork systems at velocities up to 10m/sec but I understand that when you get to the 15-20m/sec, the static regain method should be used.

It must be 25 years since I touched on this method and sadly my old college notes are somewhere in the attic, so is there anyone out there that can suggest a good source of information including static regain factors and a good worked example??

Friar Tuck of Sherwood

 

[25362]

You may find the required information in Fan Engineering by the Buffalo Forge Company, a small engineering Handbook published in 1983, edited by Robert Jorgensen. I have seen the eighth edition, but there may be more.

 

[ChrisConley]

Chapter 32 of ASHRAE's Fundamentals Handbook has some excellent worked examples. SMACNA (Sheet Metal and Air Conditioning Contractors of North Americal) has some excellent reference material, not so much on duct sizing, but on materials and specifications for high velocity systems. Also McGill has information on duct design. I've also attached a link for Howden Buffalo, where you can find the fan engineering handbook recommended in the earlier post.

http://www.ashrae.org/

http://www.smacna.org/

http://www.mcgillairflow.com/

http://www.howdenbuffalo.com/