Code_Aster ®
Version
8.2
Titrate:
Operator CALC_CHAM_ELEM


Date:
22/02/06
Author (S):
A. Key ASSIRE, J.M. PROIX
:
U4.81.03-I1 Page
: 1/4

Organization (S): EDF-R & D/AMA

Handbook of Utilization
U4.8- booklet: Postprocessing and dedicated analyzes
Document: U4.81.03

Operator CALC_CHAM_ELEM

1 Goal

To calculate an elementary field, in thermics and accoustics, starting from fields already calculated of
cham_no_ type *. Nature of the sizes concerned:

·
in thermics the starting field is a field of temperature, and one can calculate flow
thermics,
·
in accoustics the starting field is a field of pressure, and one can calculate the intensity
accoustics, and acoustic pressure.

These fields are calculated:
·
maybe with the nodes of the element _ELNO. For a given node, they are different from an element
with the other,
·
maybe at the points of integration _ELGA.

Let us note that one can also have access to the field (at the points of Gauss!) co-ordinates of
points of Gauss, obtained directly starting from the model.

·
Product a concept of the cham_elem_ type * or * indicates the name of the size.

For mechanics, the fields (forced or deformations, efforts generalized, energy,
indicators…) must be calculated with ugly command CALC_ELEM [U4.81.01].

Handbook of Utilization
U4.8- booklet: Postprocessing and dedicated analyzes
HT-62/06/004/A

Code_Aster ®
Version
8.2
Titrate:
Operator CALC_CHAM_ELEM


Date:
22/02/06
Author (S):
A. Key ASSIRE, J.M. PROIX
:
U4.81.03-I1 Page
: 2/4

2 Syntax

chamel
[cham_elem_ *] = CALC_CHAM_ELEM



(
MODELE =
Mo, [model]




CHAM_MATER
=
chmater,
[cham_mater]



CARA_ELEM

=
carac
,
[cara_elem]



# Selection of the meshs concerned with calculation
/
TOUT =
“OUI”,
[DEFAUT]





/ | GROUP_MA
=
l_grma,
[l_gr_maille]






|
MAILLE = l_mail,



[l_maille]



INST

= N,
[R]


/
0.,
[DEFAUT]




/
# options
thermics





OPTION =
/
“FLUX_ELNO_TEMP”,








/
“FLUX_ELGA_TEMP”,





TEMP
=
temp,
[cham_no_TEMP_R]




EXCIT
=_F
(CHARGE = l_charge,
[l_char_meca]









/COEF_MULT = cm,
[R]
/
FONC_MULT

=
Fm,
[function]
[tablecloth]
[formula]








)



MODE_FOURIER
=/nh,





[I]



/
0,
[DEFAUT]



/
# options
acoustics





OPTION=/
“PRES_ELNO_DBEL”,








/
“PRES_ELNO_REEL”,







/
“PRES_ELNO_IMAG”,





PRES
=
near,
[cham_no_PRES_C]



/
# different
options





OPTION=
“COOR_ELGA”,



);

# standard of produced field: [cham_elem_ *] with:

If
OPTION
: then
[*] - >

# options thermal:

FLUX_ELGA_TEMP
FLUX_R
FLUX_ELNO_TEMP
FLUX_R

# options acoustic:

PRES_ELNO_DBEL
DBEL_R
PRES_ELNO_IMAG
PRES_R
PRES_ELNO_REEL
PRES_R

# different
options




COOR_ELGA
GEOM_R
Handbook of Utilization
U4.8- booklet: Postprocessing and dedicated analyzes
HT-62/06/004/A

Code_Aster ®
Version
8.2
Titrate:
Operator CALC_CHAM_ELEM


Date:
22/02/06
Author (S):
A. Key ASSIRE, J.M. PROIX
:
U4.81.03-I1 Page
: 3/4

3 Operands

3.1 Operands
MODEL/CHAM_MATER/CARA_ELEM

MODELE = Mo,

Name of the model on which the option is calculated.

CHAM_MATER = chmater,

Material field associated with the model Mo.

CARA_ELEM = carac,

Elementary characteristics associated the model Mo, if it contains elements of structure or
if the isoparametric elements are affected of a local reference mark of anisotropy.

3.2
Selection of the meshs concerned with calculation

The key words TOUT = “OUI”, GROUP_MA and MAILLE make it possible the user to choose the meshs
on which it wishes to make its elementary calculations of postprocessing.

/ALL = “YES”

All the meshs (carrying finite elements) will be treated. It is the default value.

/ | GROUP_MA
= l_grma

| MAILLE
= l_maille

Only the meshs included in l_grma and/or l_maille will be treated.

3.3 Options
thermics

The options of elementary calculation in thermics can be calculated starting from a field of
temperature:


TEMP = temp

The options available are:


| “FLUX_ELGA_TEMP”,

| “FLUX_ELNO_TEMP”,
Their significance is given in [U4.81.01].

3.4 Options
acoustics

The options of elementary calculation in accoustics can be calculated starting from a field of
complex pressure:


PRES = near

The options available are:

|
“PRES_ELNO_DBEL”

Calculation of the pressure by element to the nodes in decibels.

|
“PRES_ELNO_REEL”
“PRES_ELNO_IMAG”

Calculation of the real and imaginary parts of the field of pressure by element to the nodes.

3.5 Option
COOR_ELGA

Calculation of the co-ordinates of the points of Gauss of each element (continuous mediums 2D and 3D).
Handbook of Utilization
U4.8- booklet: Postprocessing and dedicated analyzes
HT-62/06/004/A

Code_Aster ®
Version
8.2
Titrate:
Operator CALC_CHAM_ELEM


Date:
22/02/06
Author (S):
A. Key ASSIRE, J.M. PROIX
:
U4.81.03-I1 Page
: 4/4

4
Examples of calculations with CALC_CHAM_ELEM

4.1 Flow with the nodes starting from the field of temperature temp in
axisymmetric FOURIER mode 1

epsno = CALC_CHAM_ELEM



(MODELE = moaxfour,


TEMP = temp,
OPTION
=
“FLUX_ELNO_TEMP”, MODE_FOURIER
=
1



);

Handbook of Utilization
U4.8- booklet: Postprocessing and dedicated analyzes
HT-62/06/004/A

Outline document