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Dear all,
I'm trying to simulate the transient behavior of a fluid and I'm finding it very difficult to capture the wetting angle.
To begin with, I only considering the idealized case.

The common approach is to apply the pressure load
p = 2 H γ
where p is the pressure (normal traction) on the surface, H is the Gaussian curvature of the surface, and γ is the surface energy
This load will of course always yield the same equilibrium shape for a viscous fluid, regardless of the value of γ.

Now, comparing with Young's relation, where one obtains a balance containing surface energies for every interface.

Hi,

I am trying to model impact damage in a composite plate made of woven plies lay-up. I have 2 questions probably basics but I can't find any clear answer and I hope someone could help me.

1) Can the Hashin damage criterion in ABAQUS be applied to a plain woven composites? I know that initially Hashin critrion was for unidirectional composites and looking at the equations I can't see how this criterion could make the difference between matrix and fibre failure in the case of woven composites, but I can't find any restriction in ABAQUS documentation.

Hello,

I am looking for any resource where I can get some data regarding the average force and its time variation with which the wind applies force onto an aircraft body especially the wing. To reframe the question in a better way: can anyone recommend a resource that has data about the wind velocity profile around the aircraft (especially the wings) or pressure/shear force profile on the boundary of the aircraft (especially the wings) during various phases in its flight. 

Hello everyone

I have a material with a compression modulus and tensile modulus along with Poisson's ratio. Are compression modulus and tensile modulus related to the Lame` constants? Or does this material fall under 'cubic symmetry' which needs three elastic constants? In that case, how are they related to the elastic coefficients (C12, C44 or C11)?

I need to incorporate these material properties in ABAQUS. How do I model this material in ABAQUS?

Any lead on this problem is appreciated. Thanks a lot.

--

Nikhil

Dear all,

I just finished extrusion process simulation in ABAQUS with the input of stress-strain data. Now I want to retrive the strain increment of certain element during each deformation increment. Surely one can write straininc to a *.txt file when simulating with VUMAT. But the simulation of extrusion will be extremely slow with VUMAT. So How can I get the strain increment when simulating with the input of stress-strain data? 

Best regards,

shiyao

Hi,

 I am trying to model a sheet of Poly Vinyl Butryl (PVB), which is a viscoelastic material in ANSYS. I have all the regular properties like elastic, shear and bulk modulus, poisson ratio, denstiy and damping factor. I also have a stress- strain curve of PVB. With all this data, is it possible for me to find the various constants in the viscoelastic models using ANSYS?

 Thanks

Saurabh 

I have a question regarding simple torsion of a circular shaft with a uniform cross section. Given a hollow circular shaft with inner radius R1 and outer radius R2, length L, shear modulus G, fixed-free boundary conditions and applied torque T about the central axis, the equation for the rotation angle at the end of the beam is

 phi = T*L/(J*G)

where J = pi/4*(R2^4-R1^4)

Hi,

I am working on delaminated composite materials. For analysis I was trying to use ansys or lusas but not able to model proerly . I need help to model the following problem.

32 layer laminated plate length 300mm

width 250mm

delaminated between 8th and 9th layer from the top and location is  100mm from left eadge and delaminated width 50mm. Simply supported in all four eadges.

lay ups are symmetric and assume any material property (E11, E12, E22, nu, G12 etc)

Problem : buckling load and mode shape to be determined.