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Communication between Matlab and Nastran

Submitted by jadav.das on

Hi All,

 Could you please tell me how I can make communication between Matlab and Nastran? Actually I want to send some force data from Simulink to a deformable object in Nastran and then I will read the deformation of the object in Simulink. After that I will recalculate the forces and send it back to Nastran till some desired criteria is made. Can anybody help me to figure out this? Could you please pass it to me if you have any source code?

Thanks in advance

Jadav

New methods of analyzing indentation experiments on very thin films

Submitted by Li Han on

Abstract - Indentation experiments on very thin films are analyzed by employing a rigorous solution to model elastic substrate effects. Two cases are discussed: elastic indentations where film and substrate are anisotropic, and elasto-plastic indentations where significant material pile-up occurs. We demonstrate that the elastic modulus of a thin film can be accurately measured in both cases, even if there is significant elastic mismatch between film and substrate. 

This manuscript has been accepted for publication in Journal of Materials Research.  

Consistent linearized tangent moduli for hyperelastic materials... is it always a positive definite matrix?

Submitted by Mario Juha on

In order to obtain numerical solution of problemsthat involves a hyperelastic material model, we use what is known as incremental/iterative solution techniques of Newthon's type. The basic idea is to contruct a discrete system of nonlinear equation, KU=F, and solving it using a Newton's method or a modified version of it. As we know, its lead to a systematic linearization of the internal force vector and by the chain rule to the linearization of the material model.

Cohesive material zone model and ABAQUS subroutines

Submitted by Angelos Irakleidis on

Hello,

I'd like to ask if anybody knows if it is possible to use an ABAQUS usersubroutine that could vary some parameters (τmax, kn or ks etc) of the cohesive zone model of ABAQUS with the vertical pressure applied on the interface. The new ability of ABAQUS to support cohesive behaviour in contact surfaces seems very interesting and useful, however how could somebody simulate the interface under a compression - shear regime that may follow a Mohr-Coulomb type behaviour?

In-surface Buckling of Silicon Nanowires on Elastomeric Substrates

Submitted by Jianliang Xiao on

Buckling of thin layers or aligned arrays of stiff materials on elastomeric substrates has many important applications, such as stretchable electronics, precision metrology and flexible optoelectronics.  These systems show one common phenomenon, the stiff thin layers buckle normal to the substrate surface (out-of-surface buckling).  By contrast, we recently reported for the first time that silicon nanowires (SiNWs) on elastomeric substrates buckle only within the substrate surface, i.e. in-surface buckling.  Experimental process to obtain buckled SiNWs is described.

How do i find the bearing stifness of a ball bearing, theoriticaly

Submitted by BENSON THOMAS on
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HI,

How do i find the bearing stifness of a ball bearing, theoriticaly.. is there any advanced software for finding bearing stiffness

Aerodynamics of Flapping Wings for Biomimetic Flying Devices

Submitted by ADINA Support on

We present an interesting application of ADINA FSI in the

analysis of biomimetic flying devices. Please see

http://www.adina.com/newsgH62.shtml

You can find many other examples of applications of ADINA in the

analysis of multiphysics problems here:

http://www.adina.com/multiphysics.shtml

[Newton-Raphson Iteration in Transient Thermal Analysis

Submitted by shrimad on
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Hi,



I have been quite confused about this for sometime now. It
has not been mentioned clearly in the books/references that I have
looked into.



In transient thermal analysis with implicit scheme
or the Crank Nicolson scheme, are there Newton Raphson iterations based
on the residual vector in every time-step?







Thanks,

Shriram

--

Process Engineer

Moore Nanotechnology Systems

Keene, NH - 03431