Ansys problem

Discussion in 'Software' started by amateur mariner, Mar 31, 2009.

  1. ilgazcan
    Joined: Mar 2005
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    Location: TURKEY

    ilgazcan Junior Member

    ansys unit system

    Hi you can find ansys unit system table at the attachment.I want to ask a question about this table.

    You will see SI unit systems on the table as milimeter and meter.
    If we use SI unit system as milimeter what will be gravity force's value 9,81 m/s2 or 9.81e-3 m/s2(because of tonne) . Or will we chose the gravity force as 9.81m/s2 for all unit systems.
    How does ansys consider gravity force.What are your comments about it.

    Best regards

    Attached Files:

  2. alidesigner
    Joined: Nov 2006
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    alidesigner Senior Member

    All FEA is unitless and deals with Force, Stiffness and Deflections. Results are calculated based on these. So to work out your units for gravity, it depends on your density units as well. F=ma, m= volume x density.

    Just make sure your units are consistant throughout.

    You should buy Building "Better Products with Finite Element Analysis" by Vince Adams (link to Amazon page is )

    Its out of print but every now and then it comes up second hand on Amazon

  3. Ad Hoc
    Joined: Oct 2008
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    Location: Japan

    Ad Hoc Naval Architect


    If you're unsure, make a very very simple model. Apply a force and see what the results are when compared with hand calculations. Then repeat with 'g' to see what the result is. Then you'll know...

    Failing all that, read the manual!
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