iMechanica

A Report of the United States National Committee on Theoretical and Applied Mechanics (USNC/TAM), June 2007  

Recentely we did a MD simulation work on the nano-void growth in Copper, welcome to my blog for any discussion..

Why The Impact Factors of Journals in the field of mechanics is Too Low in comparison with Chemistry?

Please see attachment for details of Computational Mechanics researcher openings at Industrial Research (www.irl.cri.nz), a Crown Research Institute in beautiful New Zealand.

The role involves the application of advanced modeling and simulation methods to research on solids and structures, with an emphasis on complex systems such as composites and meta-materials, or solids with multiple defects and discontinuities.

The position is research oriented but also provides opportunities to consult with industry on commercial projects.

Candidates with expertise in theory and computation of elastic wave propagation, the mechanical behavior of composites, structural dynamics, or acoustics are encouraged to apply.

Hello,
 I need some detailed informations about topics below:
 Single material ALE
 -Advection schemes
 -Mesh smoothing algorithms
 Multi-material ALE
 -Volume fraction weighted stress
 -Interface reconstruction
 -Moving mesh techniques
 FSI
 -Constraint based method
 -Penalty based method
 -Leakage
Can anybody help me?

Thanks alot

From Prof. Jaydev P. Desai at University of Maryland:

Post-Doc position at University of Maryland, College Park:

Abstract

At iMechanica, almost none talks about topics from structural dynamics and design, theory of machines, automotive mechanics, space mechanics, etc.

Let me help correct this situation by raising two questions below. Well-thought answers from any individual are welcome.

First, some background for the questions.

The Computational Science and Engineering Program of the University of Illinois at Urbana-Champaign is seeking highly qualified candidates for two research programmer positions. The positions are in the general area of Computational Solid Mechanics. Successful candidates will develop and implement parallel computational tools. Candidates should be able to interact with faculty and students from a wide variety of UI engineering and science departments, and be prepared to work closely with U.S. government and industry researchers.

The programme for the 28th Risø International Symposium on Materials Science has now been finalized (see http://www.risoe.dk/Conferences/symp28/programme.aspx ).

 The Symposium is held at Risø National Laboratory, The Technical University of Denmark, 3-6 September 2007. 

 To sign up for the conference, please register up via the Symposium homepage: http://risoe-forms.risoe.dk/RISMS/RISMS_registration.asp  

Newton's laws of motion

First
An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Second
The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

Dusan Krajcinovic, retired professor of mechanical and aerospace engineering at Arizona State University, passed away on August 10, 2007, after a long illness.  Dusan was active in the mechanics community.  In addition to his teaching and research activities, he was a past member and chair of the Applied Mechanics Divison of ASME.  He also served a term on the U. S. National Committee on Theoretical and Applied Mechanics. He authored the book Damage Mechanics published by North-Holland in 1996.  He will be missed by all those who knew him.

In July 2007, my friend of a consulting company contacted me for recruiting a computational mechanics engineer. I told him that all my graduate students found jobs, and there are not many mechanics students in our small department. So, I posted his ad at iMechanica. Only after one week, he asked me to withdraw this ad! Why?

Because many high-qualified applicants contacted him in one week and, he’d give the offer right away.  I believe this example is an index of active user groups of iMechanica.

Thank you for your interest shown in my previously posted work.  Here's a post-print for an article of an extension to my previous work.  Extension in the sense that the MD simulation was performed on "larger" metallic nanowires (2.0 nm to 6.0 nm), and the behavior of gold (Au) nanowires were studied.  The mechanism behind strain-induced amorphization was explained and the phenomenon of multiple necking was observed, implying the presence of "localized" amorphization instead of a "globalized" one observed in shorter nanowires.

doi:10.1016/j.engfracmech.2007.07.022 

Huang, Nano Lett. 7, 2335 (2007); Philip Ball, Nature 448, 396 (2007)
Watch movies at: http://pubs3.acs.org/acs/journals/supporting_information.page?in_manuscr...  

See attachment for announcement of a Structural FEA Engineer position at Schlumberger's Sugar Land Product Center
 in Sugar Land, Texas.  If interested, please respond to Sepand Ossia (sossia@slb.com).

A cohesive law for carbon nanotube/polymer interfaces based on the van der Waals force (JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 54 (11): 2436-2452 NOV 2006)

Authors: Jiang, L.Y., Huang, Y., Jiang, H., Ravichandran, G., Gao, H., Hwang, K.C. and Liu, B. 

Our paper on the Mechanical threshold stress (MTS) model for 6061-T6 aluminum has been accepted by JoMMS.  There are several things of interest in the paper:

1) The use of a phonon drag model to predict the sharp increase in flow stress at strain rates above 10,000 /s.  This behavior is seen in a  number of materials and is hard to fit using standard power law plasticity models.  Our model does a good job in this regard.

Hello every body,

As most of you know, fracture mechanics of polymer materials needs a special consideration of the viscoelastic material properties. Especially under thermomechanical loading the role of glass transition temperature T_g is very important. That is why people try to characterize the material with different methods including stress relaxation based on Time-Temperature superposition or DMA test.

To: Engineers, Fracture Analysts, Mechanicians, Physicists...

In science and engineering, we have an excellent tradition: naming a physical unit using the name of a prominent personality from the concerned field. For example, in SI system, we measure force in newton, work in joule, power in watt...

But the unit of fracture toughness, i.e. KIC, is too lengthy to pronounce: (mega) pascal-underoot-meter. Further, it has also been in use for something like half a century by now, perhaps more. So, how do you like the idea of giving a name to this unit?