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#1 Re: Code_Aster usage » Braking a rotor » 2015-01-08 16:56:01

Hello.

Code for apply angular acceleration in static analysis:

#density
dens=7800;

#angular accelerations
ACC_EX=10
ACC_EY=20
ACC_EZ=30

#definition inertia loads
F_X=FORMULE(VALE='(ACC_EY*sqrt(X*X+Z*Z)*cos(atan2(X,Z))*(dens))*(-1)+(ACC_EZ*sqrt(X*X+Y*Y)*sin(atan2(Y,X))*(dens))', NOM_PARA=('X','Y','Z',),);
F_Y=FORMULE(VALE='(ACC_EX*sqrt(Y*Y+Z*Z)*sin(atan2(Z,Y))*(dens))+(ACC_EZ*sqrt(X*X+Y*Y)*cos(atan2(Y,X))*(dens))*(-1)', NOM_PARA=('X','Y','Z',),);
F_Z=FORMULE(VALE='(ACC_EX*sqrt(Y*Y+Z*Z)*cos(atan2(Z,Y))*(dens))*(-1)+(ACC_EY*sqrt(X*X+Z*Z)*sin(atan2(X,Z))*(dens))', NOM_PARA=('X','Y','Z',),);
 
ACC_ANG=AFFE_CHAR_MECA_F(MODELE=MODEL,
		FORCE_INTERNE =(
				_F(TOUT='OUI',
				FX=F_X,
				FY=F_Y,
				FZ=F_Z,
				   ),
                                ),
                                );

#2 Re: Code_Aster usage » Angular accelerations » 2015-01-08 16:39:32

Hello.

Code for apply angular acceleration in static analysis:

#density
dens=7800;

#angular accelerations
ACC_EX=10
ACC_EY=20
ACC_EZ=30

#definition inertia loads
F_X=FORMULE(VALE='(ACC_EY*sqrt(X*X+Z*Z)*cos(atan2(X,Z))*(dens))*(-1)+(ACC_EZ*sqrt(X*X+Y*Y)*sin(atan2(Y,X))*(dens))', NOM_PARA=('X','Y','Z',),);
F_Y=FORMULE(VALE='(ACC_EX*sqrt(Y*Y+Z*Z)*sin(atan2(Z,Y))*(dens))+(ACC_EZ*sqrt(X*X+Y*Y)*cos(atan2(Y,X))*(dens))*(-1)', NOM_PARA=('X','Y','Z',),);
F_Z=FORMULE(VALE='(ACC_EX*sqrt(Y*Y+Z*Z)*cos(atan2(Z,Y))*(dens))*(-1)+(ACC_EY*sqrt(X*X+Z*Z)*sin(atan2(X,Z))*(dens))', NOM_PARA=('X','Y','Z',),);
 
ACC_ANG=AFFE_CHAR_MECA_F(MODELE=MODEL,
		FORCE_INTERNE =(
				_F(TOUT='OUI',
				FX=F_X,
				FY=F_Y,
				FZ=F_Z,
				   ),
                                ),
                                );

#3 Re: Code_Aster usage » Normals on shell elements » 2014-10-15 18:43:37

Thank you very much for your answers.
They have helped to solve the problem.

#4 Re: Code_Aster usage » Normals on shell elements » 2014-10-15 18:11:09

Johannes_ACKVA, thanks for information.

But, i have torus under inner pressure. If i orient normal for all elements by single vector, that for half elements faces i have positive pressure (from inside to outside) and for other half elements i have negative pressure (from outside to inside).

Can i orient normal for each element?

#7 Code_Aster usage » Normals on shell elements » 2014-10-15 13:20:23

Nikon6260
Replies: 6

Hello

I'm have problem with shell model (it's the first time using the shell model in Code_Aster).
An error orientation normal to the elements, even though I have them oriented team ORIE_NORM_COQUE with default settings.
Groups OSHN1, OSHN2, ... is inseparable group of elements.
Tell me what I'm doing wrong.
Mesh file, command file and the output file in the attached zip.

Thanks

Denis

#8 Re: Code_Aster usage » ANSYS to Code Aster Input Model Translator » 2014-09-13 18:54:04

Hello!

I wrote a ANSYS to ASTER converter.

It's alpha version of macros.

Macro in the attached file.

Macro, not all can.

Close-up still has some limitations.

Limitations: -
- Export mesh only to  *.msh-file;
- Only the static linear analysis and only the elastic properties of materials;
- Only 3D models boundary conditions (can not create thickness for shell elements, the cross sections for the beam elements and the mass for mass elements), but can write mesh of any dimension (1D, 2D, 3D);
- Can not create a contact interaction.

Using a macro:
- Copy the macro to the working ANSYS directory;
- Enter text to command line: ans2ast, ARG1, ARG2
where:
ARG1 = 0 - EXPORT MESH ONLY - DEFAULT (ONLY *.MSH - FILE)
ARG1 = 1 - EXPORT MESH AND BOUNDARY CONDITIONS (LOADS, THEMPERATURES, DISPACEMENTS,...      - *.COMM - FILE)

OPTION ARG2 is only available when ARG1 = 1
  ARG2 = 0 - do not export the COMPONENTS NAMES - DEFAULT
  ARG2 = 1 - EXPORT COMPONENTS NAMES

Some of the comments in the macro to the Russian language

Maybe someone needs.
I will be glad vyshim comments and observations.

Denis

#9 Re: Code_Aster usage » ANSYS to ASTER model and boudary condition translator » 2014-09-13 18:39:21

Hello!

I wrote a ANSYS to ASTER converter.

It's alpha version of macros.

Macro in the attached file.

Macro, not all can.

Close-up still has some limitations.

Limitations: -
- Export mesh only to  *.msh-file;
- Only the static linear analysis and only the elastic properties of materials;
- Only 3D models boundary conditions (can not create thickness for shell elements, the cross sections for the beam elements and the mass for mass elements), but can write mesh of any dimension (1D, 2D, 3D);
- Can not create a contact interaction.

Using a macro:
- Copy the macro to the working ANSYS directory;
- Enter text to command line: ans2ast, ARG1, ARG2
where:
ARG1 = 0 - EXPORT MESH ONLY - DEFAULT (ONLY *.MSH - FILE)
ARG1 = 1 - EXPORT MESH AND BOUNDARY CONDITIONS (LOADS, THEMPERATURES, DISPACEMENTS,...      - *.COMM - FILE)

OPTION ARG2 is only available when ARG1 = 1
  ARG2 = 0 - do not export the COMPONENTS NAMES - DEFAULT
  ARG2 = 1 - EXPORT COMPONENTS NAMES

Some of the comments in the macro to the Russian language

Maybe someone needs.
I will be glad vyshim comments and observations.

Denis

#10 Re: Code_Aster usage » Angular accelerations » 2014-09-08 08:03:04

Initial question was simple:
"how I can apply angular acceleration in static analysis".

As a result we obtain a simple answer:
"it is not possible at time in Code-ASTER!".


Thanks

#11 Re: Code_Aster usage » Angular accelerations » 2014-09-07 15:48:01

keeswouters wrote:

Hoi Nikon

you cannot use angular acceleration in a static calculation.
Since an angular velocity already yields a (linear) acceleration in the part (and force dF = rho*dV*omega*omega), the forces caused by an angular acceleration will depend on the state and hence cannot be used in a static calculation.

keeswouters

I can use the angular acceleration in the static analysis.
For example, together with the linear acceleration (ax, ay, az) angular acceleration (ex, ey, ez) are used to balance the body under loads (for example Inertia relief from Ansys and Nastran).

#12 Re: Code_Aster usage » Angular accelerations » 2014-09-06 15:41:17

jeanpierreaubry wrote:

i told you just above

in AFFE_CHAR_MECA, U4..44.01, keyword ROTATION
section may change according to version
and there is a table of content at the begining

U4..44.01 (AFFE_CHAR_MECA) -> keyword ROTATION
"The key word factor ROTATION is usable to apply a field of force equivalent to the centrifugal force applying to a structure in rotation. Either OMEGA rotational speed and (ar, br, cr) the rotational axis."

Keyword ROTATION it's rotation velocity - OMEGA [rad/sec]

I need angular acceleration  [rad/sec^2].

#13 Re: Code_Aster usage » Angular accelerations » 2014-09-06 15:16:35

jeanpierreaubry
Please tell me which section to read.

#14 Re: Code_Aster usage » Angular accelerations » 2014-09-06 14:37:47

jeanpierreaubry wrote:

hello

in AFFE_CHAR_MECA keyword ROTATION
you can set agular velocity and vector direction
look in U4..44.01

jean pierre aubry

It's angular velocity, but I need angular ACCELERATION.

#15 Code_Aster usage » Angular accelerations » 2014-09-06 13:35:37

Nikon6260
Replies: 16

Tell me please, how I can apply angular acceleration in static analysis.
I can't find special keyword.

#16 Re: Code_Aster usage » ANSYS to ASTER model and boudary condition translator » 2014-08-24 15:14:39

keeswouters

It's just FEMAP
For translation ANSYS <-> ASTER need a special plugin from Nesys

#17 Re: Code_Aster usage » ANSYS to ASTER model and boudary condition translator » 2014-08-23 05:19:55

Thanks for the information.
But I not have  FEMAP or Hypermesh.
I'll write a macro on APDL.

#18 Re: Code_Aster usage » ANSYS to Code Aster Input Model Translator » 2014-08-21 19:31:04

Hello everybody.

I strongly need a ANSYS to ASTER model and boundary condition translator. Anybody has it?

Thaks

Denis

#19 Code_Aster usage » ANSYS to ASTER model and boudary condition translator » 2014-08-21 10:11:20

Nikon6260
Replies: 7

Hello everybody.

I strongly need a ANSYS to ASTER model and boundary condition translator. Anybody has it?

Thaks

Denis