# Hydrodynamic analysis of OC3-Hywind spar buoy

**URL:** <https://forums.nlr.gov/t/hydrodynamic-analysis-of-oc3-hywind-spar-buoy/1103>\
**Category:** Computer-Aided Engineering Software Tools\
**Created:** [April 9, 2015, 6:22am UTC](https://forums.nlr.gov/t/hydrodynamic-analysis-of-oc3-hywind-spar-buoy/1103 "2015-04-09T06:22:50Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![Jason.Jonkman](https://dub1.discourse-cdn.com/nrel/user_avatar/forums.nlr.gov/jason.jonkman/32/3086_2.png) [@Jason.Jonkman](https://forums.nlr.gov/u/Jason.Jonkman)\
**Post date:** [April 18, 2015, 2:07pm UTC](https://forums.nlr.gov/t/hydrodynamic-analysis-of-oc3-hywind-spar-buoy/1103/6 "2015-04-18T14:07:28Z")

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Dear KongLi.Goh,

The mass, CM, and inertias of the OC3-Hywind system are given in my Nov 16, 2012 post in the following forum topic: [Inertial Moments of OC3-Hywind Components](http://forums.nlr.gov/t/inertial-moments-of-oc3-hywind-components/610/1). The mass of 7,466,330 kg is only of the spar (including ballast); the total mass of the system pertinent to the RAO calculation is 8,066,000 kg, as given in the post linked above. I’m not sure what you mean be VCG = 1, but the VCG should be -78 m, as given in the post linked above.

Best regards,

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