Hydraulic Turbine Wicket Gates

[21121956]

Hello everybody:

Even though I know that it is a rare or strange query, I find myself in the painful situation of asking a simple question: do any of you know about the existence of a reaction hydraulic turbine (Francis or Kaplan), which has Guide Vanes (Wicket Gates) of two different types?

Thanks in advance for your comments.

El que no puede andar, se sienta.

 

[saplanti]

Francis Turbines have STAY VANES and GUIDE VANES (wicket gate) as far as I know. I am not aware of another development in the turbine industry in last decade. If so it will increase head losses and there is no space for it either. The following website show the image of these vanes:

https://www.mechanicalbooster.com/2018/01/francis-turbine.html/stay_guide_vanes

 

[21121956]

Hello everybody:

Hi saplanti. Well, I'm sorry I didn't make myself understood. I'll put it this way: I know very well the elements of a reaction turbine. In relation to the Guide Vanes, these are in multiples of 4, that is, 20, 24, etc.

My question is if, of those 20 or 24 Guide Vanes, 10 can be of one design and the remaining 10 or 14 can have a different trailing edge profile than the other 10.

Thanks for answering.

El que no puede andar, se sienta.

 

[saplanti]

If the designer company has done the same for stay vanes I understand the logic. Today companies are working with CFD, and developing the volumetric and mechanical efficiencies, and trying to eliminate unwanted vibrations on the turbine shaft through runners. However, I have not seen any of these applications as you mentioned, not even in publications.

Do you have a gate arrangement drawing that shows both types of wicket gates with open and closed conditions¿ It might be a clue.

I suggest you ask the supplier company why it is the case, or it might be even a mistake. Asking stupid question sometimes corrects many things.