[mr.hardcore.engineer]

Hello all,

First post! This seems like a very active forum with people that know what they're doing, so I am very much hoping for some expertise I'm trying to design an axial hydraulic turbine. I created a blade and am currently simulating this in CFX.

I have read on here, a few times, that the operating point of a turbine is when torque goes to zero. Is this the same as what I can expect from calling the (torque_z()@R1 Blade function? What I don't understand is, how is the blade actually generating power without generating torque? If I could load the blade with a counter-torque (from the electric motor), can I expect the turbine to try to maintain speed and generate a torque?

Currently, to find my operating point, I put a total pressure on the inlet and static on the outlet. Then, I do a parameter sweep of RPM. This kind of gives me a mass flow rate to work with. I plan to use these around my 'operating point', then keep rpm constant and sweep mass flow rate for a more accurate solution. It seems that a CFD analysis likes to have a mass flow at either inlet or outlet, as opposed to pressures.

Any input or examples would be highly appreciated! I'm very new to this..

thanks -

Stephen