×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

How to select a mechanical filter using PM figures

How to select a mechanical filter using PM figures

How to select a mechanical filter using PM figures

(OP)
Folks-
I need to control the incoming (dry ) air provided to cool a hydrogen fuel cell and the cleanliness of the air is stated as follows:
Fine particles (PM 2.5)<20 micrograms/cubic-meter
Coarse particles (PM 10)<50 micrograms/cubic-meter.
where PM stands for Particulate Matter and the 2.5 and 10 refer to the aerodynamic diameters of the particles in microns.

I passed this reqt on to an air filter mfgr and they didn't know what to make of it.  Can anyone out there provide some direction on this?  If a major air filter mfgr can't figure it out how am I supposed to?  I appreciate all inputs!
Thanks!


I called an air filter company and they didn't know what to make of this.


Tunalover

RE: How to select a mechanical filter using PM figures

Ugh.  To convert from an aerodynamic diameter to a true diameter, you'd have to know the density of the material (or range of densities, or a probability distribution of density), and then make assumptions about the shape of the particles so that you could estimate the drag coefficient (Cd) and back-calculate a (real) particle diameter.

I would just assume the "aero diameter" is equal to the true particle diameter and go from there; but would also make that assumption very clear to the end user.

RE: How to select a mechanical filter using PM figures

I would start looking for HEPA filters that will work with your air flow requirements.

http://en.wikipedia.org/wiki/Hepa

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources