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hi,

I am doing static stress analysis. in my problem, I have to update my input file after each increment. so for updating the input file, I have to do some calculation depend on the output of the previous increment result. for these calculations, I have to call the odb file after each increment, do some calculations, update the input file and the process will go on. I have written a python script for the calculations from the odb file but don't know how to use this script after each increment.

thank you

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 Dear All,

Recently, I am simulation a rolling process with a very high dynamic speed (around 5 m/s). Hence, the model is quite dynamic and not Quasi-static.

I use Abaqus Explicit for this simulation. The structure is composite material including several layers with different material properties. In this case, I am using ''Cohesive Surface'' definition as the surface interaction between different layers. 

I have a big problem and there is an error during the simulation process so called:

I have used Newmark's method wherein my damping matrix was non diagonal. Can we use Newmark's method if my damping matrix was non diagonal?

Dear all,

I am interested in carrying out transient analysis of structure where I have load on model as a "acceleration time history" from shock standard.

I have a question that in such case I have to do analysis as a normal transient analysis or any response spectrum analysis is needed for same? is any dynamics is involved in such problem?. Actually I am a mechanical engineer and not familiar with response spectrum analysis .

I am performing analysis in ANSYS 15.0 mechanical.

I will appreciate if anybody helps me in this regards

Hi Everyone,

I am new to the subject of finite element method. I have been trying to get proficient with the software ABAQUS.

Hello everyone,

My doubt is related with the obtenion of the true stress when using incrementally linear constitutive models (hypoelastic models). These models, alternatively to total stress strain models, related increment of strain and increment of stress. The predicted stress is obtained by adding to the previous stress the stress increment obtained by using the tangent matrix. By using total stress-strain models it is clear that the true stress is obtained by substituting the current strain into the constitutive equation. How do we do this for hypoelastic models?

I am confused by the definition of the variation of the velocity gradient in the Abaqus Theory Manual (4.6.1).

Normally δL = δ(grad(v)) = grad(δv); where δ denotes the variational operator.  But in the manual its given as δL = grad(δu); where u is the displacement field.

Could someone explain how the definition in the Abaqus theory Manual came about? I have attached a screen capture of the definition given in the manual.

Hello,

I am developing a solver implemeting Polygonal Finite Element Method (PolyFEM). Currently my code can handle n-gons with nmax=6 (hexgon).

I am trying to test the code with comlex geometries for which I need to obtain polygonal meshes. PolyMesher developed by Dr Paulino's group can obtain polygonal mesh using voronoi doagrams but the code doesn't provide control over the maximum number of edges of a polygon in mesh and ends up creating octagons etc. Hence I am thinking of using a code which can convert a structured  T3 mesh into hexagonal mesh.