Learning Forum

[Paul-Adrian Oprea]

I am simulating an axial turbine stage with a cooled stator and a rotor. The stator has holes inserted in SpaceClaim and then meshed and coupled with rotor TurboGrid into CFX. I defined the interfaces for the cooled air (air volume-blade; blade-segment volume and air volume-segment volume) and I defined the cooling air inlet with 0.05 kg/s and 850 K. The problem is that I get 99.8% efficiency which is impossible because I also simulated the turbine without the cooling holes and I have ~87% efficiency. The residual monitor for efficiency goes down to 98 and then rises again up to 99.8 where it converges. I work with a variable mixture fluid. I ran out of ideas of how to solve this problem, can someone give me a hint? The thing is when I change the temperature for the cooled air up to the same temperature of the fluid inside the turbine, the efficiency drops, but the point is to cool the blade.

[C N]

Hello Paul,

I need more information on why you are getting this high efficiency . Please send some screenshots related to the boundary conditions and set up files 

Thanks

Chaitanya Natraj