Computational Mechanics Forum

Dear abaqus users,

                 I would like to know if it is possible to specify solution dependent boundary conditions in abaqus? Let me explain my question in detail.

Hi all

I want to use LSDYNA to model a detonation process involving fluid structure interaction. A solid structure is embeded in a viscous fluid media. Due to symmetry of the model, a quarter of the model is analysed. So my question is 

1) How to model the symmetric condition in the Euler element domain? since the Euler meshes is fixed, it seems applying constraint on the nodes in the symmetric plane is meaningless.

2) How to model the infinite boudanry condition in the free surface of the fluid Euler domain?

Thanks

 Wei

I know that contact detection is generaly separated in two steps : a neighbourhood identification phase  and a detailed contact check.           

Hi,

 I have a 100x100 4-node plane strain problem. I need to apply different values of Young's modulus for each element in this model. The data of E for each element is created by  some random methods and contained in a text file.

How can I deal with this problem?

Thanks,

Hung 

Discusssion on Crystal plasticity

(1):How to establish a model which reflect the size effect in material

(2):How to form the finite element implementation of equilibrium field equation

I hope to have discussion with you in these topics

My E-mail: zhangxu26 [at] 126.com (zhangxu26[at]126[dot]com)

Hi everyone

I need help regarding material modelling in Ansys.
Actually we have obtained the stress-strain behaviour for slurry
infltrated fibre concrete experimentally. For FE modelling of a
circular ring of this SIFCON. I want to assign actual values in the
available material models. I tried to input + and - sign for tensile
and compressive stress-strain values respectively in multilinear
isotropic, but it did'nt accept -ve values. Suggestions from experts
are welcome.  If anymore detail is needed to clarify this querry I
can provide.

Hello Everybody,

Monaghan suggested for the SPH velocity correction an epsilon value of 0.5. If i use that in my code, my fluid behaves like pudding, not like water. It behaves like water when i use 0.001 or something similar. My start conditions are: rho = 1000, smoothing length h = particle spacing dx, sampling neighbours within a radius of 2h. Has anybody an idea? 

Regards,

Frank

I am really confused about this.

It seems hourglass mode is a kind of spurious modes and produced by selective or reduced integration in computing the element stiffness matrix, but I am not clear about the detail.  And I also want to know if there are any spurious modes other than hourglass mode?  Should all spurious modes be zero energy modes? Should rigid body mode be spurious modes?

 Hope someone can explain these questions in detail. Thanks!

NB - I edited this post cause I wanna u know I fixed this problem, before you read, ...

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