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FEM

Rayleigh damping and numerical damping. (Ls-Dyna vs Msc.MARC)

Submitted by Italo Persechino on
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Hi to all of you!



I have problems about dampings.



I have used Msc.MARC to simulate a Hopkinson bar experiment. We usually use a

"numerical damping" in these analysis.

As you know, MARC is a implicit FEM and it takes a lot of time to complete each

simulation.

So, I want to use Ls-Dyna, but I have the problem of damping. In Ls-dyna, we use

the Raylegh damping: there are 2 coefficients that multiply the matrix of

stifness and mass.

Is there any relation between these two kinds of dampings?

Sr. Packaging Mechanical Analyst at Apple

Submitted by Jie-Hua Zhao on
 Sr. Packaging Mechanical Analyst
  • Job Number: 25557504 
  • Santa Clara Valley, California, United States
  • Posted: Jan. 3, 2013
  • Weekly Hours: 40.00

Job Summary

Mechanical engineer working in the central IC packaging group.

Key Qualifications

FEM modelling of braided composites

Submitted by Abhinav Tripathi on

I am doing simulation of fiber reinforced composites, for that I have modelled a cubic REV. However , when I am constraining the opposite faces' node displacement sum to be 0 and coupling the nodes in each face in the direction perpendicular to the area, ANSYS is coming out . I have tried this on i7 processor with 8GB RAM system. I am confused if its a RAM problem or a model problem. If there are too many constraints if I apply coupling as well as constraint???

Numerical Simulation of Particle Stress and Fracture using FEMDEM: Application to Process Catalysts

Submitted by marigom on

Supervision:

Dr JP Latham, Dr Jiansheng Xiang

Industry Contacts:

Principal Investigator - Dr Michele Marigo

Co-investigators - Dr Mikael Carlsson, Prof Hugh Stitt

Applications are invited for a PhD studentship to join AMCG (Applied Modelling and Computational Group) in the Department of Earth Science & Engineering.

Postdoc opportunity in the field of computational mechanics

Submitted by Jan Ocenasek on

Description

New Technologies Research centre at the University of West Bohemia (Czech Republic) invites applications for a Postdoctoral position in the field of Computacional Mechanics of Materials. Highly motivated individuals holding a PhD in Mechanics, Materials Science or closely related fields are encouraged to apply.

FEM versus FFT

Submitted by DoQuangHuy on

Dear all,

In micomechanics, homogenization of heterogeneous
materials based on FEM is traditional. Homogenization based on FFT technique has been recently found (in many literatures) to have much more advantages
in term of accuracy, computational cost and resource consumption.

I am wondering why FEMs are still
widely used in education, research, and industries of
generally
computational
mechanics ?

Please could anyone help me to clarify
my question?

Thanks

PBC implementation in equilibrium equation

Submitted by xiashengxu on

Hi, guys,

 Do some of you know how Periodical Boundary Condition is implemented in equilibrium equation while using FEM:

div{ C:sym[grad(u)] } = 0 ,where the displacement u is periodical.

Is there any (detailed) documentation about this stuff?

 

Thank you very much!