we have GE 9fa gas turbine and having high combustion dynamic and high frequency band. what would be the reason and what should be do? we have dln2.0 for this machine.

 

Spreads are caused by mechanical problems with combustion hardware. When accompanied by high dynamics, that's an even worse indication.

It might also be a plugged fuel nozzle.

 

thank u for reply, but GE already change the fuel nozzle many times. what is your suggestion?

 

My suggestion?

GE have matrices and Fishbone diagrams for troubleshooting problems like this. If they've changed fuel nozzles, then it's likely not a fuel nozzle problem (is it?).

What does GE say to do next, based on their matrices and troubleshooting diagrams?