2 replies to this topic

[SadiqChemy]

Hello

 

I have some question about the multistage centrifugal compressor with intercooling between them :

 

• When we talk about the efficiency , should we consider the efficiency of each stage or we assume that the efficiency is the same for all stages (overall efficiency)?
• polytropic processes is a real process that are applicable in the industry , right ? Is there an isentropic compression in reality  or all compression are polytropic ?

Thanks

[SadiqChemy]

I am waiting !

[shan]

Who are we? 

If we are university professors, we may discuss single stage compressor efficiency to make the question clear and simplified. 

If we are plant engineers or operator, we more care over all compressor efficiency (all the stage) just as we don't care our money is in the left pocket or right pocket.

 

All the gas compression processes are polytropic processes (PV^n = C).  Isentropic compression is a special polytropic process with n=Cp/Cv.  Isentropic compression is reversible process (entropy change = 0), which is not exist in the real life per the 2nd Law of Thermodynamics.