Dear @Jason.Jonkman
It seems that ElastoDyn, same as FAST v7, does not have the ability to calculate torsional deformation. My team found in simulations using Bladed v4.3 (also modal method) that it had more than 5% effect on blade flapping results, even though the 1st twist natural frequency was well above 15P. I know BeamDyn can already calculate the results of torsional deformation, but why doesn’t ElastoDyn make the related improvement? What problems might be encountered when adding torsional degrees of freedom to the ElastoDyn code?
Best regards,