How to get hydrodynamic drag and inertia forces and fore aft, side to side forces at base of tower.

Wind & Water Structural Analysis
1

Sir,

I was a beginner in FAST and I was working on Fragility analysis of NREL 5MW wind turbine on OC3 monopile foundation. I was not understanding how to get hydrodynamic drag and inertia loads on monopile foundation. In 5MW offshore baseline OC3 monopile hydrodyn v2.03. input file there was nothing mentioned in output channels about hydrodynamic forces, except Wave1Elevation. And in old version ( hydrodyn v2.02.) these were mentioned in output channel of input file. But FAST v8 was not running with that old version hydrodyn input file. So please help me how get those hydrodynamic loads.

And In 5MW offshore baseline OC3 monopile Elastodyn v1.03. input file, regarding fore aft, side wise, vertical forces at bottom of tower was not specified in output channels. But in 5MW offshore baseline OC3 monopile Elastodyn v1.01. these output parameters were mentioned. But when was trying to run those files with FAST v8 it was not running. Can you help me with these two problems.

Hope you understood my question.

2

Dear Dhaneesh,

You can add output parameters to both ElastoDyn and HydroDyn in the OutList sections at the bottom of their respective input files. The ElastoDyn outputs are documented in the OutListParameters.xlsx spreadsheet provided in the FAST v8 archive. The HydroDyn outputs are documented in Appendix C of the draft HydroDyn User’s Guide and Theory Manual: wind.nrel.gov/nwtc/docs/HydroDyn_Manual.pdf.

I hope that helps.

Best regards,

3

Thank you sir