In our Power station we have GE Frame-9 (MS9001E) gas turbines. I have doubt and could not understand how wheel space temperature is lesser than exhaust gas temperature can any body clarify me please.
I thank you in advance

 

Well, we don't deal in doubts here at control.com. We answer questions to the best of our ability. So, here is an answer to your question.

The intent is for hot combustion gases (above exhaust temperature) NOT to enter the wheelspaces (which are "below" the turbine nozzles and buckets) and to pass through the turbine stages where the energy is removed and transferred to the turbine shaft.

Further, the wheelspaces are cooled by Cooling and Sealing Air.

So, the wheelspace temperatures should not be anywhere near exhaust temperature.

The next time you see a turbine "on the half shell" during maintenance, have a look at the seals on the turbine wheels and the case diaphragms which are designed to keep the hot combustion gases from entering the wheelspaces.

Hope this helps!

 

Thank you very much CSK