Definitions

[Jamie7963]

Hi,

I was having a look through the documentation and how the keypoints on the blades are calculated. I noticed that the sparcap position is defined using offset_y_pa, which inside pynumad is referred to as the sparcap offset or 'scoffset_hp'. I wanted to know more about how this was defined. Is that it is the distance from the pitch axis to the centre of the sparcap, along the chord length?

[kbonney]

Hi @James-Ilosta,
As you noted, the scoffset_hp variable is pulled from the windIO variable offset_y_pa, which is defined here in the windIO docs. I believe the picture below will help to answer your question:

Please let me know if you need further clarification.

I'll also note that we plan expand our shearweb related code to be more flexible. This will include the use of the start_nd_arc and end_nd_arc quantities as an alternate method for locating the position of the shearwebs for better compatibility with prebend and twist.