FEM

PhD position(s) are available for Spring 2016 semester to perform theoretical and computational work on phase field modeling of variaous structural changes in engineering materials and modeling of interaction between phase transformations and plasticity. MS degree and background in continuum and computational mechanics is required. Please send vita to Prof. Valery Levitas (vlevitas@iastate.edu).

Info about Prof. Levitas group can be found at

Study on the elastic response (macroscopic deformation) of mesoporous silicon upon capillary condensation of water in the pores published in Applied Physics Letters (APL 106, 261901 (2015)).

Check out Dr. Tim Fuller's work at http://nbviewer.ipython.org.

-- Biswajit

I am hiring an Engineering Intern this year. The candidates are expected to be graduate students with solid training in mechanics and programming. The starting date is expected to be this summer, however, it can be also earlier. This opening does not sponsor visa application and the candidates should be currently enrolled in US universities and is expected to return to the same school after the internship.  Please email your resume to jhzhao at apple.com.

You will be working on stress simulation of electronic components and sensors with a group of brilliant minds here in Apple’s Headquarters. You are a graduate student with good academic standing majoring in Mechanical Engineering, Engineering Mechanics or similar engineering fields. You are a good programmer and familiar with Python. You must be authorized to work in US. The intern position is open immediately. Send your resume to Jeff Zhao (jhzhao at apple.com).

Help needed!! in Abaqus

I have UMAT written to update stress and material tangent components for a user defined material model. I need stretch ratio as an input for my material model. For this I am using deformation gradient from UMAT. Problem is, when there is constant strain (strain rate = 0), for example when material stretched to 100% strain (rubber) and then held at that strain for certain time to see stress relaxation, the deformation gradient should give the same value of 100% strain, but to my surprise this is changing. Can any one help me with this.   

   Hi, 

         I'm now start to learn cohesive zone model based FEM for crack problems. According the a regular coehsize model (bilinear for example), the relative displacement and the cohesive stress are both unknwon, so iteration is required. My question is that what are the regular iteration steps?

Thanks. 

Hello,

I have to do a FEA regarding impact damage and delamination propagation in a CFRP specimen.

I have to do this using cohesive element in order to see the propagation of the delamination front in the material.

My problem is that I don't know how to do this in Abaqus.

I'll better explain: I can use this software but is the first time approching composite behavior and I really don't know how to model that.

I am modeling a plate under three point bending with Abaqus. The plate
is a sandwich structure with aluminum plate (thickness: 5mm), adhesive glue (thickness:
0.02mm) and a kind of foam (thickness: 15mm) bonding together. Their Young’s
modulus is at the order of 100GPa, 1MPa and 100MPa. While in incremental
calculation, the job is always be aborted for not achieving convergence. I just
wonder whether the cause of not achieving convergence should be attributed to
the huge difference in Young’s modulus.

800x600

Hello,

Hello Everyone,

I have to simulate and find the pressure on the splines in the universal joint. I have to define contact surface and to find a simple method to run analysis on this joint. I am finding it very difficult to select all the surface on every spline. Also, it will make the simulation very big.

Could anyone please help me to find a method or an easy way out. Any kind of suggestions are most welcome.

 Regards

Prahel 

Hello,

I guess I know how to descretize and further processing but how can I make or define my sample for example(tensile sample) in fortran. 

Dear colleagues,

I have one question concerning the TSHR (transverse shear stresses) output request in application of Thick Shell S8R elements in Abaqus/standard. 

the follow qarning occurs:  Output request tshr is not available when *transverse shear stiffness is specified on the *shell section definition or a material in the shell has been defined without *elastic

 Can anybody please help with an advioce or two, on how to solve this?

all the best

Matej