Steam Turbine Performance Curve
Steam Turbine Performance Curve
(OP)
I have a performance curve(steam rate vs. horsepower) for a single stage turbine (back pressure type)at a certain inlet/outlet steam conditions (temperature and pressure). How can I modify this curve for the other steam inlet/outlet conditions (such as different inlet pressure or temperature or different outlet pressure)?





RE: Steam Turbine Performance Curve
Each machine has it's individual operation cheq. curve.It is depended on the inlet condotion, outletcondition of steam.It means temp,& pressure, Purity of steam, Vacuum in condenser ,if condensing turbine. For the back pressure turbine efficiency depend upon the backpressure, inlet pressure, stage efficiency, Bearing efficinecy, Electrical Generater efficiency, Governor throlling pressure loss.
If u modified the operating curve ucan condisider the above things.
Thanks,
RE: Steam Turbine Performance Curve
Other related threads are
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In brief, without the original manufacturer's prediction program based on the actual turbine details, performance predictions may be adjusted based on ratios of available energy; "DESIGN A.E." vs. "ACTUAL A.E."
The corrections are generally made to one variable at a time. The accumulated corrections are more uncertain as the number of off-design parameters increases.
RE: Steam Turbine Performance Curve
RE: Steam Turbine Performance Curve
The fact that the "curve" is a straight line is a simplification in the first place.
A steam turbine is a volume flow device. Corrections for different operating conditions, if based solely upon changes in the available energy at design conditions vs. off-design conditions, will not include the changes in aerodynamic behavior due to differing volume flow at different loads and/or different steam conditions. Changes in load cause more significant changes (i.e. errors) in correction factors than (small) changes in steam conditions.
Consult a good text on turbomachinery design, or a text more specifically concerned with turbine performance (K.C.Cotton, Salisbury, Horlock, Balje, Stodola, D.G.Wilson,...) Don't be put off by the age of some of these books; there are also more recent texts, but the fundamentals of this subject are not new, and you are interested in the fundamentals.