I am running the rotating turbine case. I seperate the whole domain to three regions: 1.stationaey circular region;2. rotating annular region that includes the blades(the blades is treated as the no-slip wall boundary condition); 3. statinary outer region. The connection method of the interfaces between 1 and 2 , 2 and 3 is GGI and frame change is transient rotor-stator. The cel expressions are used to obtain the torque at the blades. Sometime torque is positive and sometime torque is negative. Who could you tell me the definition of the torque in the CFX 10? No matter what direction the turbine rotates, does it mean that positive torque is making it rotate in the direction which the turbine rotates, but negative torque is making it rotate in the opposite direction that the turbine rotates?

I am running the rotating turbine case. I seperate the whole domain to three regions: 1.stationaey circular region;2. rotating annular region that includes the blades(the blades is treated as the no-slip wall boundary condition); 3. statinary outer region. The connection method of the interfaces between 1 and 2 , 2 and 3 is GGI and frame change is transient rotor-stator. The cel expressions are used to obtain the torque at the blades.The global coordinate is chosen. The blades rotates around z axis. From the results, sometime torque is positive and sometime torque is negative. Who could you tell me the definition of the torque in the CFX 10? I have a problem that whether no matter which direction the turbine rotates, positive torque is making blades rotate in the direction which the blades rotate, but negative torque is making it rotate in the opposite direction that the turbine rotates?

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Hi friend, i am also solving same kind of problem i.e. CFD analysis of WINDMILL ROTOR (blade of airfoil shape)let us some discussion with me.