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I Would like to include failure in my model

Submitted by hdeepu25 on

I am doing my master thesis on crash simulation of plywood (7 layers-orthotropic material) structures in buses using explicit LS-DYNA FE program. I would like to include failure in my model. Right now I am working on Mat_054_55 (MAT_ENHANCED_COMPOSITE_DAMAGE…..material model from LS-DYNA material library).

 

Mat_054_55 allows me to get failure by defining anyone of the following parameters,

Simple strategies to produce perfect long range order in self-assembly

Submitted by Pradeep Sharma on

In a recent rapid communication (see attached paper), using principles of pattern formation, we expose some simple stategies to reliably produce perfect long range order in self-assembling systems. Most self-assembling systems exhibit short ranged order. This imperfection is detrimental to several practical applications. It is almost always possible to produce perfect patterns in small domain sizes but self-assembly over a larger areal span results in defects.

Composite analysis using SHELL99

Submitted by nadderdolatabadi on

I'm trying to model a composite structure with shell 99 element in Ansys.

I set the thickness and material no. in real constant and prepare an orthotropic material property for that. While ploting the result, as I expect to get the stresses among layers different from other points, but the result is a kind of uniform isotropic graph.

I don't know if any setting other than real constant and material property should be done to get a true result or not. and if I'm true then how can I read the true result.

I will appreciate any help.

Postdoctoral position in Computational Solid Mechanics - School Of Mechanical Engineering Purdue University

Submitted by marisolkoslowski on
A postdoctoral position is available starting Fall 2008 in the area of computational solid mechanics. A successful candidate is expected to have a strong background in multiscale modeling and programming experience. While experience in plasticity using finite element methods or dislocation dynamics is a plus , all outstanding candidates will be considered.

mold filling simulation with flo3d

Submitted by masood_star on

 

I want to simulate mold filling of a bar mold with a semisolid alloy by means of FLOW3D cfd package. but there are some problem. for example when I input a file I encounter an error like "level   1 error in subroutine rdstl: level   1 error in subroutine rdstl"in preprocessor. what can I do? does my .stl file have any faults?

other problem with another project is that when i want to solve the problem I encounter an error like "convective flux exceeded stability limit".repeatedly. is my meshing insufficient? how can I solve that too?

Using user subroutine UMAT in abaqus

Submitted by sanjay2008 on

Hi,

     Thanks for the earlier feedback. I was able execute the user subroutine (UMAT) along with *.inp file only to land into new type of error message:

fatal error lnk1112: module machine type 'IA64' conflicts with target machine type 'X86'

Can somebody please help me to understand what this error means and how to overcome this monster.

I have already installed intel fortran compiler, and microsoft visual studio for windows. 

As always thanks for the much needed help. 

 

Journal club theme of Aug. 15, 2008: Variational formulations in fracture mechanics

Submitted by Adrian Lew on

This issue of the journal club addresses a topic deemed classical by most mechanicians: the onset and evolution of fracture in brittle solids.  In the last ten years or so a community of mathematicians have been analyzing the formulation of fracture mechanics models.  Although still at a very early stage, there is already a substantial body of work, which either sets in a very rigorous settings some known results, or give rise to other perhaps more surprising ones.

Measurements of near-ultimate strength for multiwalled carbon nanotubes and irradiation-induced crosslinking improvements

Submitted by Horacio Espinosa on

For more than 15 years, carbon nanotubes (CNTs) have been the flagship material of nanotechnology. Researchers have conceived applications for nanotubes ranging from microelectronic devices to cancer therapy. Their atomic structure should, in theory, give them mechanical and electrical properties far superior to most common materials.