A Query Regarding the Calculation of Rotor Inertia for the 5MW Reference Wind Turbine in FAST v8

Wind & Water Rotor Aerodynamics
2

Dear @Yangyudong.Liu,

Just a few comments:

  • The rotor inertia as of the NREL 5-MW baseline wind turbine as computed by ElastoDyn and reported in its summary (.ED.sum) file is 38.7 * 10^6 kg * m^2. So, I_Drivetrain from your Eq. 1 is 43.8 * 10^6 kg * m^2.
  • ElastoDyn output RotTorq is not the aerodynamic torque; rather, RotTorq is the reaction torque within the low-speed shaft, that can differ from T_Aero when the rotor is accelerating or decelerating. T_Aero is available in OpenFAST via AeroDyn v15 output RtAeroMxh. This topic has been discussed in other forum topics, e.g., see: Resistant moment of the rotor and of the electric generator.
  • I’m not sure I understand why you can’t run OpenFAST; can you clarify?

Best regards,