Beamdyn

[ptrbortolotti]

I've run SONATA and WISDEM iteratively trying to converge on a blade model whose properties are similar in both ElastoDyn and BeamDyn

The biggest change consists of widening the TE reinforcement to be able to reduce its thickness so that it can physically fit within the TE of the airfoils
The second change is to increase the gelcoat from 0.5 mm to 1 mm. This is an arbitrary change simply dictated by the inability of SONATA of meshing extremely thin layers with planar elements

With these two changes, the properties between the two models converge much better than earlier, here some plots

I understand the weaknesses of following such approach (especially the 1mm of gelcoat) and I'm happy to open a discussion about this

[ptrbortolotti]

Here some more numbers to support the discussion

OLD
blade_mass (kg)
69632.99080278483
flap frequency from precomp properties (Hz)
[0.53804583, 1.63995087, 3.27593986, 5.72196246, 8.95385048]
edge frequency from precomp properties (Hz)
[0.795076 , 2.26137495, 4.76504455, 7.90710355, 13.21405013]

NEW
blade_mass (kg)
68521.2274541931
flap frequency from precomp properties (Hz)
[0.530261 , 1.62965661, 3.26993621, 5.66243605, 8.78032832]
edge frequency from precomp properties (Hz)
[ 0.74932353, 2.1823747 , 4.53225416, 7.67685026, 11.3298784 ]

[ptrbortolotti]

1P is 0.125 Hz
3P is 0.375 Hz
6P is 0.750 Hz

6P might be problematic with the new design and we could further reduce TE reinforcement thickness

[gbarter]

Pietro,

Thank you for laying this out so clearly. You went above and beyond in tracking the differences and impact. From the NREL toolchain point-of-view, this makes a lot of sense. I see it this update as better capturing the originally intended design and doesn't require a re-optimization of the blade shape and support structure. However, I also have in mind Jenni's comment that ontology changes to the blade are currently difficult for her to capture in HAWC2 without enlisting Frederik's help. I am curious to hear her perspective in our next conversation after the Easter holidays there.

[gbarter]

Seems like we are consolidating on the beamdyn branch. Can we resolve the HAWC2 conflicts and merge out this PR?