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Simulation CFD

Active Contributor
33 Posts
0 Kudos
Registered: ‎11-02-2011

Multiple Fan System

290 Views, 1 Replies
02-21-2012 08:52 AM

I am trying to run a simulation with two identical fans operating in parallel, pulling air through an enclosure.  In theory, this should double the volumetric airflow through the enclosure.  However, what I am seeing is one fan operating on its fan curve at an expected p and Q, while the other fan is effectively not functioning.  It's p value is high and the Q value very low, and the values are not even on the fan's operating curve.


I have double checked all boundary conditions, input flow directions, and materials.  They are all as they should be.  Have you ever observed this in your models?  What is causing this?  How do I fix it?

Product Support
662 Posts
232 Kudos
Registered: ‎08-24-2011

Re: Multiple Fan System

02-21-2012 09:00 AM in reply to: pwilkins

I would suggest that you check out the following first:

  1. Double check the units of the fans
  2. Double check flow direction
  3. If the fan material is the same for both make 2 different materials (change the name, but same properties) and apply 1 material to each fan.
  4. Make the mesh uniform for the fans and confirm that you have at least 4 nodes going through the thickness of the fan.
  5. Contact us in support outside of the forum and we can take a look at it on our end.



Royce Abel