Dew point for exhaust gas

[engy74]

I know the composition (in weight and in volume) of the exhaust gas from a gas turbine.
How can I calculate is dew point?
Thanks

 

[TD2K]

Assuming the exhaust gas is at atmospheric pressure (reasonble) and you know the exhaust gas composition, you know the partial pressure of the water vapor in the gas (mol fraction water * 14.7 psia). You can use the steam tables to then see at what temperature you start to condense water.

Depending how much sulfur is in your fuel, you might also have to check for an acid gas dewpoint.