×
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

VFD vs. damper controlled fan efficiency

VFD vs. damper controlled fan efficiency

VFD vs. damper controlled fan efficiency

(OP)
I am trying to evaluate the savings benefits of installing a VFD controlled fan. I can estimate the potential power usage of the VFD by applying the affinity laws because I have a good air flow demand profile for the system.

However, the current operation uses outlet dampers and/or inlet vanes to control the air flow. I am trying to figure out how to calculate the current power consumption as baseline usage. Is there an equation I can use to estimate fan power usage as a fuction of damper controlled flow? Is the power load profile different for inlet vane control than outlet damper control? I have the fan motor data but I do not have a fan performance curve. Is a fan curve necessary for my purposes?

RE: VFD vs. damper controlled fan efficiency

No equation but there are performance charts available comparing all (3) systems. VIV bottoms out at about 45% turndown.

RE: VFD vs. damper controlled fan efficiency

(OP)
Can anyone provide a source for these types of performance charts?

RE: VFD vs. damper controlled fan efficiency

Do a google image search for "outlet damper variable inlet variable speed"

RE: VFD vs. damper controlled fan efficiency

ABB used to provide software for comparing the different technologies on fan or pump systems.

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