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contact damping coefficient

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 I'm modelling an impact of a rigid body with a deformable plate (shell elements) in the dynamic explicit analysis. When defining contact parameters, I can add the damping coefficient. I'd like to know what value is typical for this parameter? After some computations, I've found that 0,01...0,05 was rather good for my model. Is that a reasonable value?


tigerofmahdi's picture

run scrip in abaqus

hi every body:


    offsetField='', offsetType=MIDDLE_SURFACE, region=Region(


    mask=('[#1 ]', ), )), sectionName='Section-3', thicknessAssignment=


Yonggang Huang's picture

Congratulations to Professors Jan Achenbach, Zdenek Bazant, Pol Spanos, Zhigang Suo and Wei Yang for receiving the ASME awards

In addition to the ASME awards related to the Applied Mechanics Division, some prestigious society awards will be given to mechanicians at the IMECE, Houston, Texas, in November 2012.

Professor Jan Achenbach  of Northwestern University will receive the ASME Medal.  [ASME Medal, established in 1920, is the highest award that the Society can bestow and is to recognize “eminently distinguished engineering achievement.”  Only one ASME Medal may be awarded annually.]

When will a stiffness matrix become non-symmetric?

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Hello, I would like to know under what situation will a stiffness matrix in a FEM problem become non-symmetric? Is there any good reference to this topic? Thanks.

How to design vanes in unsymmetrical elbows

Hi everyone,

I want to ask, does anyone know how to design vanes for unsymmetrical elbow? At least can you give me some calculation recommendations to design it? I am doing air simulation inside ductings for my final project. Thanks all

Safety Factor and Material Factor or Amod, what is the difference?

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Hello, everyone! When talking about allowable stress, Safety Factor is introduced. While in offshore engineering, there are allowable stress modifier in API and material factor in NPD. So what is the difference between safety factor and allowable stress modifier or material factor? Are they used in special load conditions?

You help will be appreciated. Many thanks! 

Ares Rosakis's picture

Ares Rosakis, Chair of the Executive Committee of the Applied Mechanics Division, ASME

Awards will be presented at the AMD Banquet, scheduled on Tuesday, 13 November 2012, during the ASME International Mechanical Engineering Congress and Exposition, to be held in Houston, Texas, 9-15 November 2012 at the Hilton Americas and the George R. Brown Convention Center.

 2012 Society Awards:

residual stress and strain definitions (through-thickness) in ABAQUS/Explicit

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Hello everyone,


I need some help regarding the definition of initial residual stresses and plastic strains in a shell finite element (S4R) model in ABAQUS/Explicit.

I have determined the residual stress distributions and initial plastic strains and I need to assign these distributions to a given element set.

I understand I should be looking at:


 ELSET_A, S11, S22, S33

total solution time in dynamic explicit analysis

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 I'd like to know how the computation time depends on the element number in a model (dynamic explicit analysis in Nastran). When I work with a simple model which has a rather coarse mesh the function is linear, so 10 steps with the increment 0.001 is equivalent to 100 steps with the increment 0.0001. But I don't know how this dependency will evaluate if I build a much more complex model. Maybe it will be exponential?

Thank you


hi....I have one is: what is the minimum weight of a water droplet pending on the roof that it will fall question is this ...shall we use both ΔP and surface tension for the solution??? plz guid me....thanks


Bird strike on engine fan blade

Good afternoon all,

I am doing bird strike analysis on engine fan blade,I have used lagrangian simulation for this model,very high plastic strain are coming. please suggest  how to retify it and if any one have example problem of bird strike(.k file) please share it 



Subra Suresh elected to the National Academy of Sciences

Dr. Subra Suresh, material scientist and the Director of the National Science Foundation, is elected to the US National Academy of Sciences.  He is iMechanica user 190.  Congratulations!

damage to the adhesive


I work  on the damage to the adhesive.

in a abaqus please ,after viewing the results how to calculate the damage surface of the adhesive (damage rate).

thank you in advance


zidane611's picture

The ANAND model in ABAQUS.

Hi, all

   I am a newer with ABAQUS. I have to simulate mechanics of a new material with ANAND model.

   I want to know whether a built-in ANAND model was in ABAQUS6.91 right now. And how to use it? I have seen in somewhere that someone said ABAQUS 6.5 had built ANAND model, but I don't find any information about ANAND model in ABAQUS6.91 I am using now.

   I hope you can tell me something about it.

   Thank you very much.



hello ,everyone ,ask for thermal extended finite element crack growth or thermal extended finite element program code .

hello , i am new for xfem ,i want to simulate crack growth with thermal load using xfem ,have some one know what website has free thermal xfem or thermelastic xfem code ? or can send me to , material is arbitrary , 2Dor 3D , THANK YOU



Alejandro Ortiz-Bernardin's picture

Professor Yannis F. Dafalias to Receive the 2012 Nathan M. Newmark Medal from ASCE

The American Society of Civil Engineers has awarded the 2012 Nathan M. Newmark Medal to Yannis F. Dafalias, a professor of Civil and Environmental Engineering at UC Davis. The award honors Dafalias’s research in plasticity of metals and soils, finite elastic-plastic deformations, inherent and evolving anisotropy, and structural optimization.

See complete post

periodic boundary conditions

Dear all,

i have implemented the periodic boundary conditions in x-directon for my simple model. In the screed i see the moement of the body in x direction. I think it is not correct. Should be additional boundary conditions be applied? Whichones?

Best regards


profilometer's picture

Scanning Valves Efficiently And Precisely Is Often A Nightmare


Traditional ways of valve inspection using a contact profilometer are making way for the more recent non contact valve inspection technologies. Even though many of the specs of surface roughness globally are set as per the findings by a contact profilometer the ease of non-contact inspection systems plus the speedier technique of employing the high tech valve inspection technologies are definitely behind why significantly more professionals are purchasing the newest non-contact profilometer.

Great things about a customized valve inspection set-up

need a johnson-cook plasticity model umat in abaqus

I need a johnson-cook plasticity model umat in abaqus。Any help will be appreciate。thanks

Mary Boyce and Huajian Gao elected to the National Academy of Engineering

National Academy of Engineering Elects

66 Members and 10 Foreign Associates

                   WASHINGTON — The National Academy of Engineering (NAE) has elected 66 new members and 10 foreign associates, announced NAE President Charles M. Vest today. This brings the total U.S. membership to 2,254 and the number of foreign associates to 206.

Jizhou Song's picture

Professor David Barnett to Receive the A.C. Eringen Medal from SES

Professor David Barnett of Stanford University will receive the A.C. Eringen Medal from the Society of Engineering Science (SES). The prize is awarded in recognition of sustained outstanding achievements in Engineering Science. Professor Barnett will receive his award during the 49th Annual Technical Meeting of the Society of Engineering Science to be held at Georgia Institute of Technology from October 9-12, 2012.

Jizhou Song's picture

Professor Markus J. Buehler to Receive the 2012 SES Young Investigator Medal from SES

Professor Markus J. Buehler of MIT will receive the 2012 SES Young Investigator Medal from the Society of Engineering Science (SES).

Huajian Gao's picture

Professor Kyung-Suk Kim to Receive Engineering Science Medal from SES

Professor Kyung-Suk Kim of Brown University will receive the 2012 Engineering Science Medal from the the Society of Engineering Science (SES). The prize, which consists of a plaque and a check for $2000, is awarded in recognition of a singularly important contribution to Engineering Science.  Professor Kim will receive his award during the 49th Annual Technical Meeting of the Society of Engineering Science to be held at Georgia Institute of Technology from October 9-12, 2012.


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