Thermal efficiency of gas turbine?
The efficiency depends primarily on size (different
manufacturtes have use similar designs). Bigger Gas Turbines tend
to more effiecient. Additional factors such as waste heat recovery
and heat exchangers can improve the system efficiency (but not the
effiecency of the actual Gas Tubine).
Smaller gas turbines such as the Rolls Royce Avons have around
25% Thermal Efficiency while larger units such as the Rolls Royce
Trent-50 have efficiencies of around 42%. A full list of Tubine
Efficiencies for different manufacturers can be found at
Note that the above comment does not make the Avon a bad unit
its simply the case that it is designed primarily for a high power
to weight ratio. Some people will also quote very high figures for
G.E Frame machines (+50%) but these numbers usually include co-gen
(a steam turbine used to recover waste heat) and are therefor not
just Gas Turbine Efficiency.
The full calculation for calculating Gas Turbine effieciency is
avalaible at VibroNurse at the following page
(http://www.vibronurse.com/turbmath.HTML) and program which does
the calculation is available at
http://www.vibronurse.com/gaseff.HTML. We use this program at our
oil and gas platforms and it works well particlauarly as a
condition monitoring tool.