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#1 Re: Code_Aster development » T-Shape Cross Section » 2022-11-25 14:09:14

in the attached picture the stress in the plate in global YY direction once properly post treated and viewed

is that what you expect as values ?

#2 Re: Code_Aster development » T-Shape Cross Section » 2022-11-25 13:11:39

hello

i did not try to run your files

but i do not think this post is in the proper section (Development) as i attach an example where EXCENTREMENT looks like working as expected

what are the dimension of  the T section

jean pierre aubry

#3 Re: Code_Aster usage » problems with the bi-linear leaf spring example » 2022-11-23 15:58:13

the views on gmsh seem quite all right to me
try and follow exactly what is explained in chapter 5.2 (5.2.1 to 5.2.4) in my book and you should obtain the desired results
this is the base of Gmsh which is quite simple and has not really changed from the very beginning (about 20 years ago)

as ubuntu and almost all the other distro do not know enough about finite elements the provided package of Gmsh are incomplete and useless with code aster, always use the one from the Gmsh download site

at this point i can hardly advise more
except that the mesh seems far too refined for this very problem (maybe elements could be 3 too 4 times larger without decreasing the quality of the solution)

one more remark on semantic
case 4 and 5 of my example are static non linear and in no way a dynamic analysis as there is no speed  involved and the time used is without any dimension

#4 Re: Code_Aster usage » problems with the bi-linear leaf spring example » 2022-11-22 16:17:18

it would help if you could post all the files of the problem
regarding coloring of the result in gmsh, if the scalar bar shows 1.16 (which is the good result) this is due to bad handling
appendix B and somewhere else in the book that are tips about howto
maybe a screen cap of Gmsh main window + option window would help

#5 Re: Code_Aster usage » Wrong bending moment from SIEF_ELGA in POU_D_EM » 2022-11-22 15:11:49

hello james-x

what i suggest is just only the normal way, not  "my" way at all

maybe reading my book chapter 4.14 would clarify what
RESULTANTE,  MOMENT, etc mean in POST_RELEVE_T
i have a specific sentance about MOMENT

please read it

jean pierre aubry

#6 Re: Code_Aster usage » problems with the bi-linear leaf spring example » 2022-11-22 13:46:47

hello

1- could you post the message file as a text file it is easier to read

2- what do you call "a reference to a solution, to get a reasonable result" ?

jean pierre aubry

#7 Re: Code_Aster usage » Neutral axis orientation of beam » 2022-11-21 09:33:14

why did not it work ?
it works for me on example !

#8 Re: Code_Aster usage » hotspots in plate stress, when plates are glue-connected » 2022-11-18 14:24:59

hello Johannes

well you did what i was thinking of!!

this does not add very much to the understanding of the problem
but
many years ago i worked in the pressure vessel industry
the CODAP french reglementation about pressure vessels with similar topics to ASME
specified that in case of finite element analysis peak stress as high as 3 times the allowable could be ignored within a small specified area where abrupt change of geometry, thickness, etc occurred
(i do not remember all the exact figures!)

but this was a wise statement

jean pierre aubry

#9 Re: Code_Aster usage » Wrong bending moment from SIEF_ELGA in POU_D_EM » 2022-11-18 14:19:47

hello

i do not think this POST_RELEVE_T will give the bending momment in a beam
maybe you should read my book and the doc

i usually do

RESU=CALC_CHAMP(
	reuse =RESU,RESULTAT=RESU,
	CONTRAINTE='EFGE_ELNO', #EFGE_ELNO contient N, VZ, MFY, etc
);
IMPR_RESU (
	_F(RESULTAT=RESU, NOM_CHAM='EFGE_ELNO',),

jean pierre aubry

#10 Re: Code_Aster usage » hotspots in plate stress, when plates are glue-connected » 2022-11-17 10:33:26

hello Johannes

i just tried out with your files

there are strange things  indeed

1- with 15.2 i  have an error in STAT_NON_LINE

2- with 14.6 if i change the gravity direction from z to y i have an altogether different stress pattern

this just a beginning

jean pierre aubry

#11 Re: Code_Aster usage » problems with the bi-linear leaf spring example » 2022-11-15 11:13:03

my own runs on 15.4 linux version
refuse ORIE_PEAU keyword and accept only ORIE_PEAU_3D
how is it possible that the windows version be different from the linux one?

as far as i know the windows version is a private venture not officially supported

but you are right the problem is not here
is is not either in the array declaration
it seems to me that it is just a matter of power of the komputer
how many cpu did you set (i do not whether this setup is available in aster study)

also the quadratic mesh is not really a practical option look at 13.4 and 13.7 in the book
the time values printed in 13.4 in the book are from a rather powerful komputer i had at the time
with my more modest today's laptop a complete run is rather in the order of 18000 s, yes 5 hours for result_5 on a quadratic mesh

i am of the old school i do not use asterstudy
i run directly code aster either from astk or as_run

edit
the difference in ORIE may come from the fact that i use
salome_meca-lgpl-2021.1.0-1-20220405-scibian-9.sif

#12 Re: Code_Aster usage » as_run does not work for me » 2022-11-14 08:43:12

hello

i experienced the same problem

the problem seems to be on existing rcdir
it looks like the developer did what they could to prevent us doing what you are trying to do

i hope this will be fixed in a later release

with quite a few hours (and the same amount of headache) to solved the problem that way

1- launch salome shell
singularity run -B /dedalus /home/dedalus/salome_meca-lgpl-2021.1.0-1-20220405-scibian-9.sif shell

2- within the shell run this command
Singularity> astk --rcdir /home/dedalus/.astkrc-154 (name is for example)
this will create this rcdir directory
and will populate it
i does not look like being automatically as it was the case previously
this will take a lot of time in the container (i do not know why)
use this command for any subsequent use of astk

3- set you problem within astk and run it
again navigating in the directories will take a long time
this will create a working . export file

4- later you can modify this . export and run it with
as_run the.export file
you can modify it for any other problem later on once you know (by experience) what to modify

jean pierre aubry

#14 Re: Code_Aster usage » problems with the bi-linear leaf spring example » 2022-11-14 08:11:47

hello

thanks for trying my examples

i expect all this troubles with the CAD files and or Gmsh will smooth down with a bit of experience

i have to investigate why the original files of the book do not run properly for result_5 in code_aster 15.4

with your own file i detected some errors
i include a corrected file with some comments
then it runs for all 5 results with good results

i do not even understand how it can run at all with the keyword errors
which version are you using?
post the message file to understand what is wrong

jean pierre aubry

#15 Re: Code_Aster usage » Neutral axis orientation of beam » 2022-11-08 09:11:50

as a former naval engineer i understand what you want
quite a long time ago i investigated about that with the following conclusions:

i did not find any way (or keyword) to apply this to the beam properties

the only way seems to apply EXCENTREMENT keyword to the plate properties
this implies that the meshing has its plane in the neutral fiber of the beam

which is cumbersome and highly impractical if you have a hull reinforced with longitudinal stringers supported by transverse  frames some of which are larger sections web frames!!

however i have never tried to use SECTION='GENERALE'for the beams and giving the properties relative to the mid plane of the plating

#16 Re: Code_Aster usage » Neutral axis orientation of beam » 2022-11-07 15:55:55

hello

you may find the beginning of an ansver in chapter 6.3 of my book

jean pierre aubry

#17 Re: Code_Aster usage » Missing normal stress in shell with beam » 2022-11-07 15:40:05

i just said this is a strange way to proceed to put CARA_ELEM and load onto entities that have not been assigned a MODEL properties
i have always tried to avoid that expect i my first junior days at code_aster

with you new set of file

are you sure that the set put under elemprop is  describing what you imply in section.png
i.e the beam is offset
i am not

regarding the stress in shell elements i suggest you read chapter 8 of my book
i prefer using several POST_CHAMP and CALC_CHAMP in that case

#18 Re: Code_Aster usage » Missing normal stress in shell with beam » 2022-11-07 13:57:09

hello

there are very strange things in your .comm file

you use GROUP_MA='SHM' to assign the DKT model
and then you use GROUP_MA='S0' to assign the elements properties
and GROUP_MA='M0' to assign the material
and 'EP0' to apply a load

no wonder you get meaningless results

use the same groups in a coherent manner

jean pierre aubry

#19 Re: Code_Aster usage » my new book "Beginning DYNAmics with code_aster" is available » 2022-11-04 15:30:22

hello miib

regarding whether this is for beginners or not, i took the pain to explain that on chapter 1.1 to 1.3
after that what is a beginner?

using it for 3D models?
why not?
try it by yourself!

jean pierre aubry

#20 Re: Code_Aster usage » Pourquoi jean pierre aubry est-il banni ? » 2022-11-03 15:58:59

hello paster

had you asked me a question about code_aster i may have known about it

i am sorry but i cannot explain you how to get banned !!!!!!!!!

jean pierre aubry

#21 Re: Code_Aster usage » Questions on Code_Aster » 2022-11-03 10:21:37

hello

i will answer any practical question (if a know the answer) you may ask here

but i will certainly not answer such a questionnaire
moreover if it requires to identify oneself with a google account

à bon entendeur salut

jean pierre aubry

#22 Code_Aster usage » satisfaction and pride » 2022-11-03 10:03:21

jeanpierreaubry
Replies: 3

from what i did here
i retained a certain satisfaction

from what i did here
i retained a certain pride

satisfaction and pride
for  a while were lost

satisfaction and pride
from now on will resume

thanks to all who showed me some support

jean pierre aubry

#23 Re: Code_Aster usage » Pourquoi jean pierre aubry est-il banni ? » 2022-11-03 09:56:17

hello mathieu

thanks

for a while i have been very sad and angry

jean pierre aubry

#24 Code_Aster usage » strange » 2022-11-01 12:09:19

jeanpierreaubry
Replies: 14

i am unable to answer some posts

#25 Re: Code_Aster usage » boundary condition of a cylindrical shaft » 2022-11-01 12:06:44

hello miib

could you be bit more explicit about what you propose