Exhaust plume calcs

[MarauderX]

Hey, so I was leafing through my ASHRAE manuals and found that I am missing my 2003 Applications.

I'm looking to calculate the plume from generator exhaust; does anyone have any spreadsheets or even just the equations needed to find acceptable dilution?

http://www.vanderweil.com

 

[atlas06]

Vanderweil, (I meant Marauder, sorry I couldn't help it, you company would not hire me 12 years ago)

I think you worry about the wrong issue.
For you to control the plume, you'd have to restrict the discharge throat out of the muffler (i.e increasing the discharge velovity), which you don't want to do, because by reducing the discharge throat, you'd create back pressure on the engine which will void your warranty and create gen set malfunction.
If anything, you want to maximize the discharge opening out of gen sets, which defeats you plume control worries.

Check this site for back-pressure calcs.

http://www.maximsilencers.com/software/silsizing.html

I'd worry more about prevailing winds, make sure that you don't have outside air intake east of the the gen set flue.


Good luck at Vanderweil.

 

[MarauderX]

Hey, thanks.
As you mentioned decreasing the velocity isn't an option, but the nature of the prevailing winds may be the biggest problem. The only thing even close is a stair pressurization fan about 30' in one direction; everyone wants to know whether the diesel fumes will manage to get inside. The short answer, by geometry, is no, but I'd like to show with a little more complex calculation.

And I better change my tag... I'm no longer with V-weil, but have moved on to grander things. I wouldn't worry about being hired there... seriously. They may be a big name in Boston, but everywhere else they don't.

http://www.vanderweil.com