Skip to main content

implementation of nonlinear fem

Submitted by phunguyen on

Hello everybody,

 In the implementation of nonlinear FEM, there are two ways, namely the Voigt notation and the full matrix notation. Obviously, using Voigt notation, one only stores vector instead of matrix. So, by using the symmetry of the Cauchy and second Piola Kirchhoff stress tensors, it is always possible to implement nonlinear FEM using Voigt notation. 

 So, my question is why the full matrix implementation still exists? It is mentioned in the famous book of Ted Belytschko. Only due to historical reason or there are some advantages? 

Faculty Position Open at The Johns Hopkins University

Submitted by vicky.nguyen on

The Johns Hopkins University, Department of Mechanical Engineering, invites applications for a full-time tenure-track faculty position in the general area of mechanics and materials. Modeling and simulations are of particular interest, but all outstanding candidates will be considered.

Ask for contact problem in ABAQUS?

Submitted by Ban.NguyenVan on
Choose a channel featured in the header of iMechanica

Hello all,

I'm modeling the railways track system, in which the rail wil be  affixed to the cross tie by Fastening to against the vertical force. 

Now instead of modeling the Fastening, I would like to model the contact between Rail and cross Tie in ABAQUS. I have try surface to surface; surface to node and also tie constrains, but somehow  the results are not reasonable (not agree to experiment result). I thinks the problem is contact properties.

So are there any one can helo me on the problem?

PDF position at the University of New Brunswick, Canada

Submitted by Zengtao Chen on

A post-doctoral position is available in the area of material modeling of composite at the University of New Brunswick, Fredericton, Canada. Particularly, expertise is sought in finite element simulation of damage/fracture and thermomechanical properties of fiber composite. Experience in multiscale finite element modeling of fracture and damage behavior of composite materials is required.

Symposium on Materials and Devices for Flexible and Stretchable Electronics at 2009 MRS Spring Meeting

Submitted by Teng Li on

Call for papers

2009 MRS Spring Meeting, San Francisco, CA, April 13-17

Symposium PP: Materials and Devices for Flexible and Stretchable Electronics

Abstract Deadline: 3 November 2008

www.mrs.org/spring2009

Dynamic fracture toughness of PMMA decreases with crack velocity

Submitted by chaumcor on

Dear Alls;

I am loking for the paper which said the Dynamic fracture toughness of PMMA decreases with crack velocity under impact loading, but after crack starts propagation, crack velocity is a decreasing function with crack propagation length.

So, if you know the paper which related to that problem, Could you please show me its title?

 

Thank you very much,

Best Regards,

 Chau

Glass thermal stress and fracture

Submitted by pinew on

I have an investigation on glass fracture in fire.

I have a fortran program and it can calculate the thermal stress with steady-state temperature and force load using finite element method, Now I want to change it to transient temperature and force load.

I wonder which method should be taken? I'd like to calculate the fracture at last.

Please help me! 

Thank you very much.

ANSYS WB/CFX FSI problem

Submitted by Nish on

I am trying to model a tube closed at the two ends by 2 plates.  The cavity enclosed by the two plates and the tube is filled with fluid.  I fix one end and apply a force to the other end.  The tube is a very flixible material and thus all the force should be present as a pressure detected by the fluid.

 When I try to do 2-way-FSI in ANSYS WB with CFX, all the force is taken up by the tube and none by the fluid.  any suggestions?