iMechanica - Fall 2006 - Comments

thanks

özkan özcan — Sat, 15 Nov 2008 18:14:57 -0500

Teşekkür ederim Barış & thanks a lot Nanshu Lu.

Best Regards

Özkan Özcan

Yuhang - Yes, I will

bjordan555 — Mon, 27 Oct 2008 10:15:31 -0400

Yuhang -

Yes, I will explain the differences, and will include this in my project report.

eigenvalue , eigensolver , eigenfrequensy , eigenmode

ho1mo — Fri, 24 Oct 2008 04:03:42 -0400

Can every body explain me about "eigenvalue , eigensolver , eigenfrequensy , eigenmode"?

Thanks in Advanced

Ho1mo

Actually the displacement

Yuhang Hu — Tue, 21 Oct 2008 21:16:54 -0400

Actually the displacement condition in the hint is consistent with the traction boundary condition. The displacement condition w=τy/μ is derived from the traction condition if ignoring the exist of the hole.

Yes! You can use PDF

Yuhang Hu — Tue, 21 Oct 2008 09:23:33 -0400

Yes! You can use PDF version.

Yes! You are welcome to

Yuhang Hu — Tue, 21 Oct 2008 09:20:10 -0400

Yes!

You are welcome to use Comsol for your project.

So we all can learn something new from you.

By the way, could you explain what the distinct advantage of Comsol is compared with other sofware? Thank you!

Comsol instead of Abaqus?

bjordan555 — Mon, 20 Oct 2008 22:23:28 -0400

I am an experienced Comsol user, and would like to use this software instead for my project. The quality of the output and its ability to solve the equations are both adequate for my project. Do you approve of this change as well?

Document Formats

bjordan555 — Mon, 20 Oct 2008 22:20:58 -0400

I do not use word or powerpoint; Can I post my report and presentation in PDF format?

Boundary conditions in Problem22

Kejie Zhao — Mon, 20 Oct 2008 21:26:51 -0400

I feel a little confused that at infinity, could the displacement boundary condition w=Ty/U and stress boundary condition Tzx=Tzy=T be satisfied simultaneously?

fracture mechanics project

LOKESH CHOUDHARY — Sat, 11 Oct 2008 01:20:55 -0400

hello

i am lokesh,pursuing M.TECH from IIT MADRAS.i want to do project in fracture mechanics.from last 2 month i am searching for a problem.i have only 5 month to complete project.can you suggest me some project about fracture mechanics.

ialso want to know about 2d and 3d crack propagation simulation.is it good problem?can we use only matlab for crack propagation simulation?i want to know other possibilities for performing crack simulation?please help me and suggest good projects,which can be completed in 5 months.

thanks

regards

lokesh choudhary

tanx

darda — Mon, 06 Oct 2008 14:57:58 -0400

Hi MS. Lu,

I found this link very helpfull.

pdf file of homework is attached

Zhigang Suo — Mon, 06 Oct 2008 09:13:13 -0400

John: The pdf file is attched. I'll remeber to do so in future.

about FSW and LBW

Xiaoteng Wang — Mon, 06 Oct 2008 06:20:58 -0400

Hi Mirko,

I think FSW is quite different from laser beam welding. Although both of them are joining process, the mechanism of FSW is far away from the traditional arc welding. So before your start, please decide which branch you should choose because both are not so easy to study. For FE simulation, I only carried out FEM calculation of arc welding, such as TIG, MIG and Laser. I highly recommend you to read Goldak's first paper of double eclipsoid welding pool model:COMPUTER MODELING OF HEAT-FLOW IN WELDS, METALLURGICAL TRANSACTIONS B-PROCESS METALLURGY 17 : 587 1986. That paper is a classical work.Another review is also good: Modeling of fundamental phenomena in welds,T Zacharia / J M Vitek / J A Goldak / T A DebRoy / M Rappaz / H K D H Bhadeshia,Modelling and Simulation in Materials Science and Engineering,3 (2), p.265-288, Mar 1995.

I dont know if the newest version of ABAQUS provides the Goldak model or not. But another FE software MSC.MARC has already succeeded in implementation of Goldak model as GUI module. Anyway you can implement the model easily using subroutines.

FSW is still very difficult to model, because the FSW is not simply melt and solidification process. Dynamic recrystallization taks place dramatically in FSW. I think the FE simulation of FSW is much more difficult than arc welding.

I'm not sure what kind of problem you are interested in, but from what you described, I think your work may be related to residual stress/strain after welding or joining process. I think it is very challenging problem because of the highly nonlinear material properties and coupled phenomena. Good luck.

Best regards.

Wang

OOo

Mike Graham — Sun, 05 Oct 2008 19:15:58 -0400

You might try installing OpeOoffice, a free/open-source office suite. It seems to dislay all the math and such properly for me and could make it easier for you to read Word documents people paste in the future.

http://www.openoffice.org/

pdf file?

John M. Kolinski — Sun, 05 Oct 2008 18:50:27 -0400

Prof. Suo, would you mind posting the .pdf file for the hw assignments? I don't have word on my computer, and google docs doesn't read some of the symbols used in the assigments.