Dear All,

I have a problem with inlet fogging of a V94.2 Ansaldo energia gas turbine. It is rated at 159 MW and by fogging system, we could only reach to about 10 MW, while we were expecting approximately 15 MW augmented power (based on OEM performance curves).

In this type of turbine, the turbine exhaust temperature is set based on compressor inlet temperature,i.e, by decreasing the inlet temperature, exhaust temperature will drop and this will limit the power increase by inlet cooling.

The amount of cooling is considerable by inlet fogging (we cooled 38 deg centigrade ambient to 17 deg centigrade, but the power augmentation is not accordingly)

Please comment.

 

Dear HER,

How many stages u have at your inlet fogging system, as you must have some stage operations for fogging system,

Also fogging system effectiveness is affected by relative humidity.

kindly mentioned detail operating parameters of your fogging system. as i understand capacity of gas turbine you mentioned must be at ISO conditions.

so at 38 Deg C what is machine output. and what you get after fogging in full operation.

 

Dear Gtman,

Thank you for your reply.

We have so many stages because we are using frequency converter on the pumps.

at 38 C, the turbine output is 103MW and it increases to 113MW after fogging, while we were expecting 117MW based on the turbine performance curves. Fogging is decreasing inlet air temperature from 38C to about 17C (i.e. 21 C cooling), because the humidity is very low (about 7%).

Waiting for your comments.
Regards,
HER

 

Dear Her

I guess that your air intake is not really suitable for a fogging application. I assume you have quite some drain coming out of the intake.

I have a solution for you, pls check "http://www.axenergy.ch/news/reference/article/upstream-system-up-running//bpid/23/".

Best regards
Philippe

 

Hello there

Just came across this posting which is old but want to know if the problem persists as we have a solution that can be provided to fix the problem .

If interested kindly email me with full details and contact information to email ID '[email protected]'
Thanks
Siva

 

Dear Sirs

This is absolutely based on your site ambient condition and Fuel and if This could have done after water washing of GTG , might have got more then 10 MW. Even if The Temp control is too high from 37 to 17, there will be drastic slow down however it could be gradually. because of sudden drop in Temp Air become more dense and Compressor has drawn more power to out put.

If any comments on this pls discuss.

> I have a problem with inlet fogging of a V94.2 Ansaldo energia gas turbine.

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try to change the TETC by increasing it. if you don't have access or permission for this increment let the I&C team to increase it, and before turning the fogging off return the TETC to it value.

> I have a problem with inlet fogging of a V94.2 Ansaldo energia gas turbine. It is rated at 159 MW and by fogging
> system, we could only reach to about 10 MW, while we were expecting approximately 15 MW augmented power
> (based on OEM performance curves).

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