Tip Accelerations along X, Y Z axes

Wind & Water Rotor Aerodynamics
1

Dear Dr. Jonkman,

Could you please clarify how the tip accelerations along the X, Y, Z axes are calculated? I’m using this relation to calculate the accelerations of a model turbine based on the original NREL 5MW turbine. Could you kindly let me know the equations used in the FAST estimations? I’m particularly interested in the accelerations along the flapwise direction.

Thank you!

Sincerely,

Aananthy Sarma

2

Dear Aananthy,

The blade-tip accelerations in the ElastoDyn module of FAST are calculated as the absolute (i.e. relative to the inertial frame) translational acceleration expressed along the local blade coordinate at the blade tip.

Best regards,