[salehi144]

Dear all,

I'm working on a Francis turbine with 15 blades and 15 splitters. I have used the traditional topology for mesh generation in TurboGrid. The mesh is not very good because of all the problems associated with traditional method and you all know them.

So, I want to use the ATM topology with single splitter method and I get following error:

"U is outside of its bounds, U=-0.003 ..."

In the user guide of TG it is said that the following condition should be satisfied for ATM single splitter:

• The main and splitter blades have rounded leading edges and cut-off trailing edges.
• The leading edge for the main blade is positioned ahead (meridionally) of the splitter leading edge.
• The trailing edges for both blades are located at the same meridional position.

The first condition is satisfied in my case. But the second and third conditions are not. It is pretty obvious that the second and third conditions are for the Pumps and in Turbines it is exactly opposite of that (Leading edges are at same place and trailing edge of splitter is ahead). Does it mean that ATM single splitter can not be used in Turbines with splitter?

Anyway, can any one help me? Do you think that the problem is for those conditions or maybe some thing else is wrong? Has anyone used the ATM topology to generate mesh for a turbine with a splitter?

thanks very much,
Best regards,
Saeed,

[tkoehler04]

I know this post was from a few years ago, but were you able to resolve this? If so, what did you find out?

Thanks in advance.

[salehi144]

Dear tkoehler04,

Unfortunately no. I wasn't able to create an ATM optimized mesh for that test case. I have used the traditional topology method.

Best regards,
Saeed

[LorenzH]

As this thread is still not really answered, i directly asked at Ansys if they have an idea how to include splitter blades in a radial turbine.

With the restriction still given for the topology it is not possible with the settings of the radial turbine. However, if you swap outlet and inlet, as well as LE and TE contour (in BladeEditor) you can trick the system. You have still the same geometry (only theta distribution must be modified).

Hope this helps.