Hi every one,

I am working in a power plant with ten gas turbines of type Frame 9E. I am asking about any information (properties) about where from can I get the graph of load and swirl angle? of course there must be a load vs swirl angle graph for Frame 9E.

 

Could someone in the forum comment on their use (success or failure) of Swirl Angle data to try and predict where high spreads on Gas Fuel are coming from.

 

bil07,

Every GE-design Frame 9E heavy duty gas turbine is NOT like every other GE-design Frame 9E heavy duty gas turbine. There are many subtle differences which can affect swirl angle, AND, of course, the major difference: the type of combustion system (conventional (diffusion) or DLN Dry Low NOx). Using the wrong swirl angle chart can lead to frustration and extra work.

The manufacturer/packager will have the swirl angle chart for the type(s) of turbines at your site; unless you can find another site which has already obtained the correct swirl angle chart AND has the same units your site has, using the wrong swirl angle chart can , again be frustrating and result in needless extra work.

Swirl angle charts, while helpful, do not reflect all possible problems which can result in high exhaust temperature spreads. Swirl angle charts are (were) developed by manually varying fuel flow to a combustor and observing the resulting swirl angle at various IGV positions and loads. They generally were done using machines operating in simple cycle mode, and there can be large differences in combined cycle machines. (Today, they're probably all produced using software simulations--but only for newer machines.) Problems like cracked combustion liners or failing side deals do not always exhibit the same swirl angle.

The point is: Swirl angle charts are not the be-all, end-all method of troubleshooting all exhaust temperature spreads. They are merely a tool, which can be used to indicate the likely area where a combustion problem (fuel flow-related) might exist. They will NOT ALWAYS point to the exact location for every type of combustion problem/issue. Many times, the swirl angle was 10° or 13° (angle) different from that indicated by the swirl angle chart, and Plant and Maintenance Managers refused to check the combustor to the right or left of the one indicated by the swirl angle chart--instead deciding to pull the combustor directly opposite the spread location, or the one 180° opposite the spread location (like throwing darts at a dart board blindfolded, angered because the swirl angle chart was wrong!).

The best place to obtain the correct swirl angle chart for your machine is from the OEM or packager of the machines at your site.

 

thanks friends

 

Dear glenmorangie and Dear All;

When I asked OEM about Swirl Angle Chart of our GT, the response I got that this chart is an internal and confidential document and NOT shareable with customer?!!

Using my personal contacts, I had succeeded to get a GT swirl angle software. The software includes several Gas turbines and mine was within. The talk is about GE MS5002 which is 12 combustors and double shaft with variable 2nd stage between the HP and LP wheels. In my case; the use of the swirl chart wasn't really successful. It helps (as a tool) to localize the sector or area of 3 to 4 adjacent combustors which may lead to the existing temperature spread at the GT exhaust. This supposed that there are no leaks and the air sealing system is working fine. And in case where your gas turbine is finishing its life(reaching MI) you just can't trust this chart.

Regards
Karim