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Unformatted text preview: ntropic turbine work ws h1 h2s
Isentropic compressor work ws h2s h1
wa h2a h1
Actual compressor work
Actual KE at nozzle exit
Isentropic KE at nozzle exit
2s In these relations, h2a and h2s are the enthalpy values at the exit
state for actual and isentropic processes, respectively.
The entropy balance for any system undergoing any process
can be expressed in the general form as
123 Net entropy transfer
by heat and mass Entropy
generation Change in
entropy (kJ/K) (kJ/kg) The work done during a steady-flow process is proportional to
the specific volume. Therefore, υ should be kept as small as
possible during a compression process to minimize the work
input and as large as possible during an expansion process to
maximize the work output.
The reversible work inputs to a compressor compressing an
ideal gas from T1, P1 to P2 in an isentropic (Pυk constant),
constant), or isothermal (Pυ
manner, are determined by integration for each case with the...
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This document was uploaded on 11/28/2012.
- Spring '09