×
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

Centrifugal Compressor capacity

Centrifugal Compressor capacity

Centrifugal Compressor capacity

(OP)
Recently i have been working on compressor performance calculation, and this is first time i am working on compressor.
I know that increase in suction pressure increases compressor capacity,acfm. As suction pressure increases, we are on left side of the performance curve so actual volume going to compressor is low.(am i right!)So, actual cfm going to compressor is low and compressor will have more capacity available.

now, i am confused for how decreasing polytropic head will increase compressor capacity ? Because when head goes down, we are operating on right side of the curve and compressor doesn't have capacity available to compress more gas? Am i going on right direction?

please explain with engineering equation.

thanks
naturalgas01
  
 

RE: Centrifugal Compressor capacity

Increasing suction pressure increases mass flow entering the compressor, thus power required to maintain the same head at increased flowrates goes up.  If power cannot be increased, flow must decrease.

You can arrive at points on the compressor performance curve in two ways.  Decreasing head and increasing flow, or increasing flow and decreasing head.  

On the left side, at low flows, head is the predominate component of power.  On the right side of the curve, flow is the predominate component of power.  In either case, available power is the limiting factor.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

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