iMechanica - modeling - Comments

Dear Prof. Hong, My name

Tung Nguyen — Wed, 26 Nov 2008 10:26:16 -0500

Dear Prof. Hong,

My name Nguyen Thanh Tung. I am looking for a PhD position in metamaterial which exhitbits the negative refractive behavior. I am getting Msc degree in Department of Physics, Hanyang University, Korea (expected Winter 2009). Is it possible for me to apply to these topics you mentioned above (still working in metamaterial field is my dream)? If you need my CV, pls take a look in this link http://www.imechanica.org/user/10026

Best regards,

Tung Nguyen

Doubts regarding FEM Analysis of Nanocomposites

nikhil satheesan — Fri, 21 Mar 2008 03:43:44 -0400

Respected Sir

My name is Nikhil S. I am a final year Engg student from T K M College, Kerala, India. I am working on a project about the FEM analysis of Nanocomposites. Sir, I would like to have your advice in this direction.

Steps I have done so far..

1) Wrote a C++ programme to generate the radius,theta and z values of a carbon nanotube with input parameters tube diameter, length and element length.

2) tried to bring it to ansys for analysis .. ( Structural Analysis)

3) Can you tell me how to model a nanocomposite from this situation in Ansys.

Expecting a favourable earliest reply

Thank you

Nikhil S

You may mail me in my email id also..

Difference in fiber reinforce composite and nanocomposites?

Mingji Wang — Tue, 20 Nov 2007 22:00:49 -0500

I am not follwoing recent development in 'nano'-mechanics. I suspect if ABAQUS can help, all classical solutions and analysis developed for fiber/frisk reinforced composites before can be borrowed directly. I will appreciate if someone can give a general description of the key differences in mechanics analysis between the classical fiber/frisk reinforce composites and nanocomposites IF we want to stay in continuum mechanics. Is it just a dimensional change (and some different stress transfer mechanism), or a totally new mechanics area? Thanks ...

Dear Dr. Xu Thank you

RaminBabaei — Tue, 20 Nov 2007 20:15:22 -0500

Dear Dr. Xu

Thank you very much for your comment and your papers .they are helpful for me.

Best regards,

Ramin

New research topics of mechanics of nanocomposite materials

Luoyu Roy Xu — Tue, 20 Nov 2007 14:34:45 -0500

Dear Ramin,

This review paper is very good but it’s still incomplete (especially mechanics analysis) and not able to report new process from 2005-2007. I’d answer your questions and provide my suggestions based on my previous experience on nanocomposite research.

Q1-what are the important parameters in the modelling of nanostructures which must be considered? A1---- I think the aspect ratio of the nanofiller, stiffness ratio of the nanofiller and matrix should be important parameters.

Q2-what is the main problem of current finite element method to model the nanostructure, especially nanocomposite materials (for example in traditional methods or in ABAQUS program)? A2-----failure modeling should be a major problem. Most of the stiffness problems including the curved nanotubes etc. have been modeled well by previous researchers. Similar to your method, we simulated a simple interfacial stress transferring problem and here is our paper published in Journal of Nanoscience and Nanotechnology(PDF file).

Q3-Can we expand traditional methods like as Rayleigh-Ritz or Least square methods to model and analysis of nanocomposites? A3--- it’ may be very hard since other researchers have solved these easy cases. You may use these classical approaches to solve stiffness related problems.

For new issues of strengths and fracture toughnesses of nanocomposites, you may read my previous article.

The interface may be important

Ying Li — Tue, 20 Nov 2007 08:29:21 -0500

Dear Ramin,

In my view, the interface between the matrix and the additions maybe the important problem. However, the ditrsbution and the orientation of additions are also very imprtant For nanocompostites, I suggest you see the review article"Nanocomposites in context" , which is very impressive.

Lee