Blower sizing help.

[jxsnyder]

I am designing a test setup for a flange-mounted mist eliminator system. The mist eliminator housing is 11.5" ID on the inlet and necks down to a 2.9" ID outlet within a foot. A mist eliminating pad (vane style) is situated within this housing. Estimated flow rates for this system range from 105 to 450 acfm at the 11.5" inlet. The testing plan is to utilize a blower to induce the flowrate through a 10" ID line to this mist eliminator. A slow increase in pipe ID will be used to reduce pressure drop. My question is how to determine the operating pressure of this system and size the blower to fit the application? I would appreciate any and all input since this is not my usual type of work. Thanks.

 

[willard3]

I would find an Engineer who does ventilation and hire him.

 

[jxsnyder]

Wow that was insightful. I am glad that by reaching out when I ran into a problem I got such a great reply.

 

[trashcanman]

Given a 2.9" dia. nozzle and up to 450 CFM, that looks like 2372 FPM which seems awfully high for eliminating mist. Most cooling coils have an air speed limit of 500 fpm to avoid moisture blow by. The pressure drop can be done by most duct design manuals, using the data for a transition. I would like to know what is trapping the moisture at that velocity.

 

[MTES93]

I think what jxsnynder has is more of process operation than a comfort cooling issue. Let me think about this for a bit and respond..... What is this stuff used for if I may be so blunt????

 

[willard3]

You should read board policies which begin as follows:


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[MintJulep]

Basically you need to know the pressure drop.

Typical approach is to ask the manufacturer of the demister.

If you are the manufacturer then you'll need to do a test.