F2A is an aero-hydro-servo-elastic tool developed based on AQWA by Yang Yang, a postdoctoral research associate in Liverpool John Moores University for performing fully coupled analysis of floating offshore wind turbines (FOWT). The aero-servo-elastic simulation capabilities are fully implemented within the user_force64.dll which is a built-in DLL of AQWA for external force calculation. For a coupled analysis of a floating offshore wind turbine subjected to wind, wave and current loadings, the aerodynamic loads acting on the rotor, the elastic responses of the blades and tower, and the servo-control are examined through the DLL, considering the influence from the platform motions. The platform position, velocity and acceleration at each degree of freedom are passed into the DLL to update the kinematics of the upper structures. Before being passed into DLL, these terms are transformed from the inertial coordinate system to the local coordinate system of the platform.
Dear Yang
I am doing multibody analysis in AQWA and FAST using F2A. My platform consists of two bodies, and a tower is mounted over body 1.
I am following the same procedure as mentioned in the User Manual of F2A for the DeepCwind model. In the User manual, it is mentioned that the "ptfmModel" must be set to 1.
When I'm running the analysis with "ptfmModel" =1 I am getting the following error,
"WARNING: Blade #1 element #4 is supersonic! Other elements are likely supersonic as well.
Supersonic mach nos. will be set to 0.7 to attempt continuation.
Angle of attack = 2.11384E+21 is outside table.
Aborting FAST."
when I am running my model with "ptfmModel"= 0, it works fine, but it generates constant power (straight line) at a constant rot speed.
Also, when I modelled my system as unibody, it worked well with "ptfmModel"=1, and I got the required time series of varying power and rotor speed.
I have already tried reducing the time step for the multibody system, but it's not working.
Dear Yang I am doing multibody analysis in AQWA and FAST using F2A. My platform consists of two bodies, and a tower is mounted over body 1. I am following the same procedure as mentioned in the User Manual of F2A for the DeepCwind model. In the User manual, it is mentioned that the "ptfmModel" must be set to 1.
When I'm running the analysis with "ptfmModel" =1 I am getting the following error, "WARNING: Blade #1 element #4 is supersonic! Other elements are likely supersonic as well. Supersonic mach nos. will be set to 0.7 to attempt continuation. Angle of attack = 2.11384E+21 is outside table.
Aborting FAST."
when I am running my model with "ptfmModel"= 0, it works fine, but it generates constant power (straight line) at a constant rot speed. Also, when I modelled my system as unibody, it worked well with "ptfmModel"=1, and I got the required time series of varying power and rotor speed. I have already tried reducing the time step for the multibody system, but it's not working.
Please guide me through this issue.
Thanks and regards