×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

validation of results

validation of results

validation of results

(OP)
Hi,
I'm a fairly new user of Pro/Mech but an experienced design engineer, and I am slowly working on my confidence level of the results that I obtain. I design things that mostly use plates so I compared the results of some round and square plates in mechanica to roark. A little disappointed so far, but maybe I am expecting too much?

Best results for a round plate (uniform normal pressure load)was to use a solid, compressed into a shell. Stress compared well (~4%) but displacement was off by about 12%.
Best results for a square plate (same loading method) was again a solid compressed to shell but in this case the deflection was right on with stress off by 15%.

Results using 'thin' protrusions was poor. Note that I varied how constraints were applied (edge & surface) and no real difference was noted. Square plate width/thk=40, round plate dia/thk=12.5. I applied light loads to ensure staying within elastic range and used 'standard' mat'l properties.

Are these results typical? I realize that these are only approximations and that integrated mode (all that I have) maybe makes the approximation even more approximate, but these usefulness of these results seem a bit questionable to me. I have spoken with some engineers who do not even question the results. Maybe I am too old or conservative to do that, but I would appreciate feedback as to others results.

Thanks in advance for your help,
Bob

RE: validation of results

The way you apply the loads and constraints are fundamental to the "accuracy" of the results.
You can install the validation models supplied on the Mechanica CD which do exactly what you are trying - validates simple analyses against theory. Maybe try these to get confidence, and examples of how these models were loaded and constrained.

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close