×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Ship hull bending analysis

Ship hull bending analysis

Ship hull bending analysis

(OP)
thread727-317253: Abaqus boundary condition help(ship hull and sea water)

Hell people,
I am newby to Abaqus, never used it before, and have taken up a project to do bending moment analysis for a ship hull, focusing primarily on mid-ship position. I will first do it for ship's self weight and then place weights at different locations along the length. I was reading the thread referenced above to start with.

1. I am wondering where do I apply the boundary condition so that I don't get free body movement? Is mid ship a good location?
2. The ship hull is symmetrical, so is it a good idea to work on only half the hull or will the results change if I work on the whole hull.

Any other suggestions to start with? I have attached a sample picture of my hull (I will remove other parts other than the hull while working)
Thank you.

RE: Ship hull bending analysis

- 1 Usually you should apply equilibrated loads the ship. then you can use an inertia relief system to analyze your ship.
Another system is to use the 3-2-1 system: http://www.roshaz.com/images/FEA_best_and_worst_pr...
you shall be very sure that your loads are equilibrated.

-2If the hull is symetrica and your loads too, you can model half a ship. in my experience this never happen and you end up by model the full ship.
regards
Onda

RE: Ship hull bending analysis

this seems like an involved project for your first model ... I'd start with simpler models, to understand the FEA better.

1) if you're interested in a section of your model, don't place the rigid body constraints there ! 3-2-1 is a good approach ... this defines a plane that will remain plane after the model runs ... choose your plane carefully and you'll get results that look sensible. The precise set of three nodes used should have little impact on the internal stresses but will affect the datum for displacements ... try some different sets to see.

2) if your ship is symmetric, use the plane of symmetry as this plane. I agree with the comment above, you'll need to consider unsymmetric loads soon enough !

another day in paradise, or is paradise one day closer ?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources