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I am trying to simulate an experiment in which a steel plate is excited using sound vibration to measure its natural frequencies and vibration patterns. Even if modal frequency analysis of the test gave results, it was not satisfactory. Therefore, the external vibration with a controlled frequency is required to be included in the FEA model. FYI, gravity load will also be considered.

I would appreciate any help, specially related to ABAQUS. If there is no way of doing this in ABAQUS, suggestion of any other FEA software would be fine.

Thanks in advance.

Hi all,

Is it possible to call an abaqus inp file ( which changes in each iteration) in python which is called from matlab? I mean, there is an abaqus inp file in matlab which is updated in each iteration. to get txt out put I decide to run this inp file in python and get the ODB output in txt file.

Is there anyone who can help me what commands I should use to call each new inp file in python?

Thank you in advance

Hello Everyone,

my question is that whats the formula or equation to find flexural wave propagation speed along the beam??

Please guide with this, I am kind of stuck in this problem.

Thanks in advance,waiting for the response...

Dear altruists,

Good day!

I am looking for elastic properties of jute,sisal,flax,kenaf,coir and banana fibers (Longitudinal Modulus and transverse modulus, shear modulus, poisson ratios). Unfortunately I am not finding them. I have gone through some papers as well. But no specific data is available. 

Could you please give any information/data regarding this?

Thanks in advance! 

Hello everyone, I want to calculate elastic constants (C11, C22, C12, and C66) for a single layer graphene sheet by MD simulation in LAMMPS. I am using the following equation:

E = (C11*C22-C12*C21)/C22 and poisson ratio = C12/C22 from this paper:

 http://www.sciencedirect.com/science/article/pii/S0261306909003082

Hello

I am a new user of abaqus.pleas help me

I want to know how can i model the axisymmetric plane strain in abaqus for a cylinder?I mean which boundary conditions should be used?and sould i consider any cap for this cylinder when i sketch it?

Thank you. 

Dear Researchers

Can you please make a correction in my Code of MATLAB

X1=[1,2,3,4]';

X2=[5,6,7,8]';

U1=[9,10,11,12]';

U2=[13,14,15,16]';

for i=1:1:4

EPS1(i,1)= U1(i,1)/X1(i,1);

EPS2(i,1)= U2(i,1)/X2(i,1);

EPS12(i,1)= 0.5*((U1(i,1)/X2(i,1))+(U2(i,1)/X1(i,1)));

defG(i)=[1+U1(i,1)/X1(i,1) 0+U1(i,1)/X2(i,1); 0+U2(i,1)/X1(i,1) 1+U2(i,1)/X2(i,1)];

end

EPS11

EPS22

EPS12

are right but for defoarmation gradient  i am getting error of 

Hello everybody,

         My task is to write a UMAT for non-linear viscoelastic material in Abaqus. When it comes to working in 2D and 3D, I see that there are places where I have to work with 4th order tensors. I understand that stresses and strains are stored as vectors in Abaqus - UMAT and are passed in and out the same way.

Hello everyone,

I'm modelling VUMAT for a composite. So, in my model I have inotropic and anisotropic behaviour. I have modelled isotropic behaviour but for anisotropic behaviour I need to use deformation gradient, which is causing errors. CAN ANYONE HELP with DEFORMATION GRADIENT. How to use that, do we need to rotate stress back in corotational form as abaqus manual says if yes then How?

How can we get Rotation matrix in VUMAT, if we can multiply it with stretch I think we have the result. May be an alternative.....

Please help, stuck badly :(