polytropic efficiency of centrifugal compressors
polytropic efficiency of centrifugal compressors
(OP)
Hello,
I am simulating centrifugal compressors in Aspenplus(ASME polytropic). As for the polytropic efficiency there is a default number however in a rules of thumb text book, I have found a graph that illustrates polytropic efficiencies of centrifugal compressors as a function of suction volume acfm.
Question 1: Is this graph a function of inlet pressure? or is it valid for any inlet pressure?
Question 2: why is the polytropic efficiency of a compressor a funciton of the inlet volumetric flow is this a thermodynamic limit in nature?
Your expert advice would be much appreciated.
Thank you
AB
I am simulating centrifugal compressors in Aspenplus(ASME polytropic). As for the polytropic efficiency there is a default number however in a rules of thumb text book, I have found a graph that illustrates polytropic efficiencies of centrifugal compressors as a function of suction volume acfm.
Question 1: Is this graph a function of inlet pressure? or is it valid for any inlet pressure?
Question 2: why is the polytropic efficiency of a compressor a funciton of the inlet volumetric flow is this a thermodynamic limit in nature?
Your expert advice would be much appreciated.
Thank you
AB





RE: polytropic efficiency of centrifugal compressors
David
RE: polytropic efficiency of centrifugal compressors
X axis of the graph is suction volumetric flowrate (acfm),
Y axis is poly tropic efficiency.
As the volumetric flow increases the efficiency increases for centrifugal compressors
Efficiency increases from the 60's and goes up to 78%, for volumetric flows from 1000 increasing to 200000acfm.
I wish I had the graph with me so I could attach it, hope it is descriptive enough.
Thank you