In Aerodyn, there are some aerodynamic output issues that need to be consulted with you.
1.In the local coordinate system of the blade, when operating under rated wind conditions, x is the out of plane direction and y is the in-plane direction. And in the shut-down case of a 90 ° pitch angle, x is the in-plane direction and y is the out of plane direction?
2. Which existing coordinate system can ensure that the output X and Y are not affected by the twist angle of each section, and point uniformly from the blade root to the blade tip towards the inside or outside of the plane? Currently only found in the outlist file inertial/global coordinate system，polar coordinate system，local-polar coordinate system.
3. Does the Z-axis of the local coordinate system of the blade always point from the blade root to the blade tip? For example, when the azimuth angle of the blade is 180 °, the force pointing from the blade to the tip remains positive.
4. When considering blade torsional loads (aerodynamic forces, aerodynamic bending moments), should we distinguish between the X and Y directions and use the results of the local polar coordinate system (l) to analyze the blade loading situation more appropriately?
Thank you very much for your help！
look forward to your reply.
The polar, cone, blade, local polar, and legacy output systems do not twist with the blade.
I’m not sure what you are describing for blades that curved or deflected, but if you are referring to the pitch axis, the coordinate systems with z along the pitch axis are the cone and blade systems (other systems could also have z along the pitch axis if the blades are not curved and not deflected).
2.Will the polar, cone, blade, local polar, and legacy output systems be affected by the pitch angle system?
4.Regardless of the pitch angle during shut-down, what my research needs is to represent the in-plane direction and out of plane direction, which cannot be affected by the geometric twist angle and node position deformation of the blade. However, for the twist direction, I need the blade itself, so I have doubts about whether the coordinate system selection in the Z direction should be different from X and Y？
There’s a new question to ask，If I want to obtain the aerodynamic load of the whole blade, Fx and Mx in the outlist document use the blade root coordinate system. May I ask：
1.If this blade root coordinate system will rotate with the blade pitch?
2. Which position does Mx, My, Mz refer to for the bending moment? At the root of the blade？
Why is the hub coordinate system of wind turbine affected by the blade azimuth angle? What I extracted is the aerodynamic load of the rotor, as follows:
When the wind turbine is shut down, the aerodynamic load on each direction of the wind turbine should be the same when the blade azimuth is 0 degrees, 120 degrees, and 240 degrees. However, in my results, only RtAeroFxh and RtAeroMxh are the same, while RtAeroFyh and others are different. Do you know the reason? (Due to the non-zero yaw angle, it is not possible to use RtAeroFxi that belong global coordinate system)
Thank you, I see your message. So, if I want to obtain the aerodynamic load of the Rotor that is not affected by rotation but is related to yaw, which output quantity should I choose? global coordinate system will move with yaw?
I would suggest outputting the rotor aerodynamic outputs in the hub coordinate and applying sines/cosines to remove the effect of rotor rotation on the y and z terms.
Where is the point of application of the forces (Fx, Fy, Fz) and moments (Mx, My, Mz) extracted via AeroDyn? Is it all at the 50% spanwise position of the blade?
