Using Mlife for a lifetime fatigue estimation

[Jason.Jonkman]

Dear Matthew,

LUlt has been discussed many times on our forum, e.g. see:

MLife Fatigue DEL Calculation

Dear Bruno, Unfortunately, the NWTC Information Portal has crashed and is no longer available, and there is a bit of gap before the new website becomes live–see the following announcement for more information: Other News. Regardless, here is what the old FAQ said regarding the question, “What values do I use for TypeLMF and LUlt in my MCrunch and MLife input files?”: Until the new website becomes live, I’ve temporarily places the MExtremes (as well as MCrunch and MLife) download(s) here: win…

Mlife - User Defined Distribution

Dear Conor, Just to be clear, the OC3-Hywind specifications report (nrel.gov/docs/fy10osti/47535.pdf) gives the Young’s modulus (E) of the tower as 210 GPa; however the yield strength (sigma_yield = E*epsilon_yield, where epsilon_yield is the axial strain at the yield strength) is not given in that report. I misread your post and was simply using your value. You’ll have to make your own assumptions on sigma_yield for your own purposes. Here are the basic equations for LUlt for a thin-walled …

Best regards,