# mechanician

## Change of basis for deviatoric second order tensors

Dear mechanicians

I remember reading somewhere that someone had a proof of the following:
Given a deviatoric/traceless second order tensor it is possible to find a basis for which all the normal/direct components equal zero.
For 2d this is easy: a basis rotated 45deg wrt. the eigenbasis.
The proof concerned 3d and it may have been Gurtin that had it in one of his books (sometihng tells me "The Linear Theory of Elasticity" (1972) as I don't have access to this one), but I'm not certain.

Can anyone help me in this matter?

## Thermomechanical coupled simulation

Hi all,

I am trying to input a termperature field as initial conditions in
abaqus, to use the temperature distribution from a previous temperature
simulation in an mechanical simulation. But when I check the Temperature
values in the mechanical simulation i get great differences between the
nodal values (NT) and the element values (TEMP).

Does anybody know the reason of this problem?

Can it be related to the element typ? So the TEMP values are the avereged values from NT?

Kind regards!

## Thermomechanical coupled simulation

Hi all,

I am trying to input a termperature field as initial conditions in
abaqus, to use the temperature distribution from a previous temperature
simulation in an mechanical simulation. But when I check the Temperature
values in the mechanical simulation i get great differences between the
nodal values (NT) and the element values (TEMP).

Does anybody know the reason of this problem?

Can it be related to the element typ? So the TEMP values are the avereged values from NT?

Kind regards!

## Thermomechanical Simulation

Hi all,

I am trying to input a termperature field as initial conditions in abaqus, to use the temperature distribution from a previous temperature simulation in an mechanical simulation. But when I check the Temperature values in the mechanical simulation i get great differences between the nodal values (NT) and the element values (TEMP).

Does anybody know the reason of this problem?

Can it be related to the element typ? So the TEMP values are the avereged values from NT?

Kind regards!

## sad news for mechanician. Departure of HD Bui, member of french academy of science

Unfortunately, HD Bui, 76, passed away yesterday evening. An elegant, dedicated, very discreet but bright mind, HD Bui made a long career at Ecole Polytechnique and EDF, making important contributions in fracture mechanics and inverse engineering.  Lately, he returned to work on his interesting contributions on the Cheops pyramid and the spiralling internal structure.

He was considered the most prominent vietnamese scientist in France, of 400 000 living there.

## Novel Rotary-Turbo-InFlow Tech - Gearturbine Project - Featured Development - Atypical Type

-Atypical - Gearturbine = Retrodynamic Dextrogiro VS Levogiro Effect - Ying Yang Thrust Way Type - Non Waste Looses. State of the Art, Innovative concept Top System, Higher Efficient Percent.

-Its Similar simple system, of the Heron`s Aeolipile Steam Turbine Device, from Alexandria; 10-70 AD.

-8/XY Thermodynamic Cycle way Steps.

-New Form-Function Motor Engine Device Type.

-Retrodynamic = Rotor/RPM VS InFlow Way = Collision interaction type.

## Novel Rotary-Turbo-InFlow Tech - Gearturbine Project - Featured Development

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Atypical Gearturbine - Retrodynamic Dextrogiro vs Levogiro Effect - Ying Yang Thrust Way - Non waste Looses. State of the art innovative concept top system higher efficient percent.

Its similar system, of the Aeolipile device, 10-70 AD.

8-XY ThermodynamicCycle way steps.

New Form-Function Motor Engine Device Type.

Rotor RPM vs InFlow way / Collision interaction type.

Non parasitic looses for; cooling, lubrication, combustion, systems.

Hello all

I have a problem with my VDLOAD file for abaqus.

## MSC.MARC (HYPELA2)

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Dear Marc specialist users Colleague:

I am developing an user material subroutine (HYPELA2) in Msc Marc (Marc Mentat2012.1.0, Windows platform, 64bit).
I am trying to make a write inside in Hypela2.f routine, but it doesn't work.
I have used the file number unit 6, for example,  write(6,*) ' Hello' , but
no any results in the standard output file. Otherwise, the Hypela2 works properly.
Does anyone have any suggestions how can I write out any data from Hypela2.f?
Thanks.

Leslie

## 6 CDs in cell mechanics(mechanobiology)

There are six distinguished biophysicist in cell mechanics field (their research interests cover much broader areas) and the abbreviations of their first names are either C or D. They are Dr. David Weitz (Harvard U.), Dr. Christopher Chen (U. Penn.), Dr. Dennis Discher (U. Penn.), Dr. Denis Wirtz (JHU), Dr. Douglas Robinson (JHU), and Dr. Daniel Fletcher (U.C. Berkeley). These six scientists use both experimental and theoretical approaches to investigate the biological responses of proteins and cells to mechanical stimuli, such as forces and geometrical constraints. Their research extends from molecular scale to cellular level to tissue level.

## link 8, introduced tensile curve and compression curve

Hi.

I'm working  with the element link8 (Ansys 12.1) and I have to
introduced the tensile curve and compression curve, but I don't know,
How I have to introduced its???

I have worked with the comands: TB: aniso, miso,..., I think the best
option is: TB, user, but How I have to introduced the values of tensile
and compression curve?, when this are different.

File attachment is the tensile and compression curve to introduce

Thank you, Toni

Hello,

I am working in a fluid mechanics theme. Do anybody now something about the Radial Reynolds Number

Thank you.

## Fractal surface mesh generation

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I would like to know a suitable way to generate meshs for fractal surfaces and export them to be used in FEM computations.

Thank you for any help.

## curvature tensor

Could someone explain me what do the curvature tensor mean at surface structures?

THX for the help!

## I want to combine XFEM and UMAT(about concrete) in ABAQUS

DEAR everyone :

I want to  combine XFEM and UMAT(about concrete) in ABAQUS,I have some questions about this ,concrete is a Special materials and I have the Constitutive equation about concrete ;Can I use the new constitutive equation and  simulate mixed CONCRETE cracking by XFEM(UEL_XFEM) in ABAQUS,how to combine UEL and UMAT in abaqus, thanks in advance,or you can Recommend  some relative infomation for me