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Code_Aster
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Version
8.2
Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
1/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
Organization (S):
EDF-R & D/MFTT















Instruction manual
U4.2- booklet: Mesh
Document: U4.25.01



Operator
DEFI_FLUI_STRU

1 Goal

To define the characteristics necessary to the dynamic study of a structure under flow.
By the choice of one of the key words factors, the user specifies the type of configuration
“structure-flow” studied: beam of tubes under transverse or axial flow, bunch of
order, coaxial hulls.
According to the type of configuration, the provided data make it possible to realize downstream:
·
a fluid study of coupling/structure: estimate of the coefficients of forces fluid-rubber bands
and calculation of the new modal parameters of the structure using the operator
CALC_FLUI_STRU
[U4.66.02],
·
projection on the modal basis under flow of one or several excitations
turbulent defined by their (S) density (S) spectral (S): operators
DEFI_SPEC_TURB
[U4.44.31] and
PROJ_SPEC_BASE
[U4.63.14]. One can then calculate the answer of
structure with the turbulent excitation, as well into temporal as into frequential.
Operator “DEFI_FLUI_STRU” produces a concept of the type
type_flui_stru
intended to be used
downstream by the operators
FONC_FLUI_STRU
[U4.35.02],
CALC_FLUI_STRU
[U4.66.02] or,
indirectly,
PROJ_SPEC_BASE
[U4.63.14].
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Code_Aster
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Version
8.2
Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
2/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
2 Syntax
typeflui [type_flui_stru] = DEFI_FLUI_STRU
(
/
FAISCEAU_TRANS: _F
(
COUPLING
=
/
“YES”
/
“NOT”
,
CARA_ELEM
=
will cara
,
[cara_elem]
PROF_VITE_FLUI
=
profv
, [function, formula]
PROF_RHO_F_INT
=
profrhoi,
[function, formula]
PROF_RHO_F_EXT
=
profrhoe,
[function, formula]
NOM_CMP =
/
“DX” [kN]
/
“DY”
/
“DZ”
,
COEF_MASS_AJOU
=
cm
, [R]
CSTE_CONNORS
=
cste
,
[l_R]
RHO_TUBE
=
rho
,
[R]
NB_CONNORS =
Nb
, [I]
/
TYPE_PAS
=
/
“CARRE_LIGN”
/
“TRIA_LIGN”
,
TYPE_RESEAU
=
/
tr
[I]
NOT =
not
,
[R]
),
/
BUNCH
=
_F
(
COUPLING
=
/
“YES”
[KN]
/
“NOT”
,
/
GRAPPE_2
=
/
“ASC_CEN”
[KN]
/
“ASC_EXC”
/
“DES_CEN”
/
“DES_EXC”
,
NODE
=
No
, [node]
CARA_ELEM
=
will cara
,
[cara_elem]
MODEL
=
model
,
[model]
COEF_MASS_AJOU=
cm1
,
[R]
RHO_FLUI
=
rho_f
, [R]
),
/
FAISCEAU_AXIAL
=
_F
(
/
GROUP_MA
=
l_grma, [l_gr_ma]
/
TRI_GROUP_MA
=
/
“root *”
/
“* root *”
/
“* root”
,
VECT_X
=
l_comp, [l_R]
PROF_RHO_FLUI
=
profrho
,
[function]
PROF_VISC_CINE
=
profvisc,
[function, formula]
/
CARA_ELEM
=
will cara
,
[cara_elem, formula]
/
RAYON_TUBE =
radius
, [R]
COOR_TUBE
=
l_coor
,
[l_R]
GRAVITY
=
l_g
,
[l_R]
ROUGHNESS
=
rug
,
[R]
CARA_PAROI =
will l_cara
,
[l_TXM]
VALE_PAROI =
l_vale
,
[l_R]
ANGL_VRIL
=
alpha
, [R]
),
/
COQUE_COAX
=
_F
(
MASS_AJOU
=
/
“YES”
[DEFECT]
/
“NOT”
,
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Code_Aster
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Version
8.2
Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
3/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A

GROUP_MA_INT
=
gr_ma_i
,
[gr_ma]
GROUP_MA_EXT
=
gr_ma_e
,
[gr_ma]
VECT_X
=
l_comp
,
[l_R]
CARA_ELEM
=
will cara
,
[cara_elem]
MATER_INT
=
mater_i
,
[to subdue]
MATER_EXT
=
mater_e
,
[to subdue]
RHO_FLUI
=
rho_f
, [R]
VISC_CINE
=
visco
, [R]
ROUGHNESS
=
rug
,
[R]
PDC_MOY_1
=
cde
,
[R]
PDC_DYN_1
=
cdep
,
[R]
PDC_MOY_2
=
cds
,
[R]
PDC_DYN_2
=
cdsp
,
[R]
),
INFORMATION =
/
1
[DEFECT]
/2, [I]
)
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Code_Aster
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Version
8.2
Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
4/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
3 Operands
3.1 Key word
FAISCEAU_TRANS
/
FAISCEAU_TRANS
Key word factor allowing to characterize a configuration of the type “beam of tubes under
transverse flow ". If the study is based on the definition of several areas of excitation, it
as many occurrences of the key word factor is necessary
FAISCEAU_TRANS
that areas.
COUPLING = “YES”
or
“NOT”
Indicator of the text type
[TXM]
specifying the taking into account or not forces
fluid-rubber bands. This operand must appear in at least one of the occurrences of
key word factor
FAISCEAU_TRANS
, and can be omitted in the others.
CARA_ELEM = will cara
Concept of the type
[cara_elem]
allowing to provide all the data relative to
geometry of the elements of the structure: useful for the estimate of the hydraulic diameter.
This operand must appear in at least one of the occurrences of the key word factor
FAISCEAU_TRANS
, and can be omitted in the others.
PROF_VITE_FLUI = profv
Concept of the type
[function]
allowing to provide the adimensionné profile speed
transverse along the tube. The parameter of the function is the curvilinear X-coordinate. This
operand must appear in all the occurrences of the key word factor
FAISCEAU_TRANS
.
PROF_RHO_F_INT = profrhoi
Concept of the type
[function]
allowing to provide the profile of density of
fluid interns with the tube, along the tube. The parameter of the function is the X-coordinate
curvilinear. This operand must appear in at least one of the occurrences of the word
key factor
FAISCEAU_TRANS
, and can be omitted in the others.
PROF_RHO_F_EXT = profrhoe
Concept of the type
[function]
allowing to provide the profile of density of
external fluid with the tube, the tube. The parameter of the function is the X-coordinate
curvilinear. This operand must appear in at least one of the occurrences of the word
key factor
FAISCEAU_TRANS
, and can be omitted in the others.
NOM_CMP = “DX” or “DY”
or
“DZ”
Indicator of the text type
[TXM]
specifying the direction according to which the forces act
fluid-rubber bands and/or turbulent forces. This operand must appear in with
less one of the occurrences of the key word factor
FAISCEAU_TRANS
, and can be omitted
in the others.
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Code_Aster
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Version
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Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
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A. ADOBES
Key
:
U4.25.01-G1
Page:
5/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
COEF_MASS_AJOU = cm
Value of the coefficient of added mass
cm
. This operand, if it is used, can not be
defined that in one of the occurrences of the key word factor
FAISCEAU_TRANS
, and can
to be omitted in the others.
CSTE_CONNORS
=
cste
List of two realities defining the interval of the constants of Connors for the method of
even name (see R4.07.04).
RHO_TUBE
=
rho
Density of the tube for the method of Connors
NB_CONNORS =
Nb
, [I]
Poins of discretization inside the interval numbers defined by the key word
CSTE_CONNORS presented above.
/
TYPE_PAS = “CARRE_LIGN”
or
“TRIA_LIGN”
Indicator of the text type
[TXM]
allowing to specify the type of pitch of
beam, defined by the arrangement of the tubes the ones compared to the others and
by the direction of the flow compared to the beam. This operand can
to appear only in one of the occurrences of the key word factor
FAISCEAU_TRANS
, and can be omitted in the others.
“CARRE_LIGN” =
not square line.
“TRIA_LIGN” =
not triangular line.
TYPE_RESEAU = tr
Whole indicator strictly lower than 1000 and positive defining
experimental configuration for which coefficients of coupling used
for the study were obtained [bib1]. This operand must appear in all
occurrences of the key word factor
FAISCEAU_TRANS
.
Note:
“tr” must appear in two files “cd.70” and “ck.71” which allows
to describe the evolution of damping and the stiffness added by the flow
according to the fallback speed
R
V
, the latter being calculated from
speed inter-tubes.

The files “cd.70” and “ck.71” are read by the logical units 70 and 71. They
have both the following structure:


Line 1 of the file: a number of correlations present as a whole of
file (whole)

*** then, for each one of these correlations, a block made up of ***

Line 1 of the block: type of pitch of the network associated with the correlation (1 if
TYPE_PAS= “CARRE_LIGN”, 2 if TYPE_PAS= “TRIA_LIGN”)

Line 2 of the block
: tr (whole well informed on the level of the operand
“TYPE_RESEAU”)

Line 3 of the block: nbplages (a number of contiguous ranges fallback speed on
which added damping and the stiffness were interpolated by the user
in polynomial form)

Line 4 of the block: nbplages real, followed from two real A and B; nbplages
the first realities correspond to the values fallback speed - ordinates by
order ascending - lower limits of the contiguous nbplages; two realities
With and B are respectively smallest and largest values speed
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Code_Aster
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Version
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Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
6/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
reduced for which added damping and the stiffness were given
in experiments on a test bench in thermohydraulic similarity; they
thus delimit the range fallback speeds inside which
correlation can be interpolated starting from the values identified on test bench.
In general, one thus chooses the first of the real nbplages equal to A and the last
real nbplages equal to B.

Nbplages following lines
: each line corresponds to the interpolation
polynomial of the correlation of damping or the stiffness added in
range considered, the first range fallback speeds extending between
first and the second of the real nbplages. On each line, 11 coefficients are
to inform. These coefficients are them
()
11
1
I
I
defining the polynomial used
for the interpolation in the range considered. Thus, for the example, indicating Cd
the damping added by the flow. The expression which will be taken by it in
count according to the fallback speed
V
R
is as follows (the expression for
added stiffness is similar):
()
()
=
-
=
11
1
4
I
I
R
I
R
V
V
Cd
Following line: a line allowing to delimit the blocks associated with each
correlation, in general of the form: “
********** “

*** fine of the block ***

If there are other correlations, Ligne 1 of the block corresponding to the correlation
following.
On the basis of number certain of tests, EDF worked out and validated a unit
correlations fluid-rubber bands allowing to simulate damping and
stiffness added to a structure by a flow. Supply of these
correlations in the shape of two files of a format conforms with that
specified Ci high will be studied on a case-by-case basis according to the request.
NOT = not
Step value reduced of the beam: report/ratio enters, on the one hand the distance between centers between 2
close tubes, and in addition the diameter external of the tubes. This operand
can appear only in one of the occurrences of the key word factor
FAISCEAU_TRANS
, and can be omitted in the others.
3.2 Key word
BUNCH
/
BUNCH
Key word factor allowing to characterize a configuration of the type “control rod”.
COUPLING = “YES” or “NOT”
Indicator of the text type
[TXM]
specifying the taking into account of the forces fluid-rubber bands.
The coupling fluid-rubber band, if it is taken into account, utilizes the coefficients
adimensional of forces fluid-rubber bands identified on model GRAPPE2, which are
used to represent a resulting force and a moment [bib2].
If
COUPLING = “YES”
, it is necessary to inform the following operands obligatorily, with
exception of
COEF_MASS_AJOU
who remains optional.
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Titrate:
Operator
DEFI_FLUI_STRU
Date:
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A. ADOBES
Key
:
U4.25.01-G1
Page:
7/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
/
GRAPPE_2 = “ASC_CEN”
or
“ASC_EXC”
or
“DES_CEN”
or
“DES_EXC”
Four possible choices corresponding to the various configurations
experimental for which the coefficients of forces fluid-rubber bands have
summer identified:
·
ascending flow stem of Centered control;
·
ascending flow stem of Offset control;
·
flow Descending stem from Centered control;
·
flow Descending stem from Offset control.
NODE = No
Identifier of the node (concept of the type
[node]
) where are applied the force and
moment resulting representing the action from the forces fluid-rubber bands.
CARA_ELEM = will cara
Concept of the type
[cara_elem]
providing all the data relative to
geometry of the elements of the structure: useful for the estimate of the diameter of
stem of control. This concept brings inter alia relative information
with the orientations of the elements.
MODEL = model
Concept of the type
[model]
providing information relating to the types of
elements of the structure.
COEF_MASS_AJOU = cm1
Value of the coefficient of added mass due to the local containment of the stem of
order on the level of the plate of housing. If modal characteristics
out of water at rest of the structure were calculated with the density
equivalent.
eq
water
beam
D
S
=
2
4
+
The coefficient
cm1
of mass added due to local containment to the level of
plate housing is given by the relation:
(
)
cm1
=
-
D H
2
2
where
D
indicate the diameter external of the stem;
S
is the surface of the cross-section
tube and
H
represent the thickness of fluid film on the level of containment.
Note:
When the user does not inform the operand
COEF_MASS_AJOU
,
cm1
is estimated automatically using this expression with
= 1.
RHO_FLUI = rho_f
Value of the density of the fluid surrounding the structure.
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Titrate:
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DEFI_FLUI_STRU
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A. ADOBES
Key
:
U4.25.01-G1
Page:
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
3.3 Key word
FAISCEAU_AXIAL
/
FAISCEAU_AXIAL
Key word factor allowing to characterize a configuration of the type “beam of tubes under
axial flow " [bib2].
Note:
If the study is carried out using a representation of the complete beam, one
authorize only one occurrence for this key word factor.
If the study is based on a simplified representation, one needs as many occurrences as there is
tubes in the simplified beam. Each tube of the simplified beam defines a class
of equivalence for the tubes of the real beam. Characteristics of the tubes of the beam
reality for the same class of equivalence (common radius, positions) are the subject of one
occurrence of the key word factor.

To be able to use a simplified representation of the beam, it is necessary that the modal base
calculated in air is equivalent to the modal base in air complete of the real beam;
each tube of the simplified beam must thus be a tube equivalent to each class of
real tubes. For example, for a class of NR real tubes, Young modulus E and of
density
, a possible equivalent tube is characterized by a Young modulus
And a density
NR
.
/GROUP_MA = l_grma
If the study relates to the complete beam: list groups of meshs
corresponding to the tubes of the beam (concepts of the type
[group_ma]
).
If the study is based on a simplified representation: the use of
this operand is obligatory and excludes the recourse to
TRI_GROUP_MA
. One is awaited
concept of the type
[group_ma]
corresponding to the one of the equivalent tubes of
simplified beam.
/TRI_GROUP_MA = “root *”
or
“* root *”
or
“* root”
Argument of the text type
[TXM]
defining the root of the names of the groups of
meshs corresponding to the tubes of the beam. The use of this operand is not
sell by auction that if the study is carried out using a representation of the beam
complete. The root can be a prefix, an intermediate character string or
a suffix.
VECT_X = l_comp
List of three realities giving the components of the directing vector of the beam in
total reference mark. The beam having to be directed according to one of the axes of the total reference mark,
only three sets of components are acceptable: (1., 0., 0.) , (0., 1., 0.) or (0., 0., 1.). This
operand is obligatory if the study relates to the complete beam, and must appear with
less in one of the occurrences of the key word factor if the study rests on one
simplified representation.
PROF_RHO_FLUI = profrho
Concept of the type
[function]
defining the profile of density of the fluid
surrounding the tubes. The parameter of the function is the co-ordinate of space
corresponding to the axis of the total reference mark directing the beam of tubes. This operand is
obligatory if the study relates to the complete beam, and must appear at least in one
occurrences of the key word factor if the study is based on a simplified representation.
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Titrate:
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DEFI_FLUI_STRU
Date:
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A. ADOBES
Key
:
U4.25.01-G1
Page:
9/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
PROF_VISC_CINE = profvisc
Concept of the type
[function]
defining the kinematic profile of viscosity of the fluid
surrounding the tubes. The parameter of the function is the co-ordinate of space
corresponding to the axis of the total reference mark directing the beam of tubes. This operand is
obligatory if the study relates to the complete beam, and must appear at least in one
occurrences of the key word factor if the study is based on a simplified representation.
/CARA_ELEM = will cara
Concept of the type
[cara_elem]
providing all the data relative to
geometry of the elements of the structure: radius of each tube. This concept
is to be provided only if the study relates to the complete beam.
/
RAYON_TUBE = radius
Radius of the tubes of the real beam for the same class of equivalence. This
operand is used only if the study rests on one
simplified representation.
COOR_TUBE = l_coor
List co-ordinates of the centers of the tubes of the real beam pertaining to
the same class of equivalence. This operand is used only in the case
where the study is based on a simplified representation.
GRAVITY = l_g
List of four realities defining the standard and the orientation of the vector gravity
G
in
total reference mark. It is necessary to provide in the order the data (G, has
p
, B
p
, C
p
) such as:
G
X
Y
Z
=
+
+
+
+
G has
B
C
has
B
C
p
p
p
p
p
p
2
2
2
The default values are: G = 9.81; has
p
= 0. ; B
p
= 0. ; C
p
= ­ 1.
RUGO_TUBE = rug
Value of the absolute roughness of the walls of the tubes, being used for the estimate of the coefficient
of axial friction. This operand is obligatory if the study relates to the beam
complete, and must appear at least in one of the occurrences of the key word factor if
the study is based on a simplified representation. A characteristic value for one
smooth steel is 10
­ 5
measure.
CARA_PAROI = will l_cara
List arguments of the text type
[TXM]
giving the names of the characteristics
geometrical of the chamber wrapping the beam. The licit arguments are them
following:
·
“TESTSTEMYÇ”
,
“ZC”
and
“R”
in the case of a circular chamber:
“TESTSTEMYÇ”
,
“ZC”
co-ordinates of the center in any plan X = X
0
along the axes of the total reference mark
perpendiculars with the beam and ordered such as (
X
,
Y
,
Z
) is direct if
X
is
the axis of the total reference mark directed according to the beam.
“R”
radius.
·
“TESTSTEMYÇ”
,
“ZC”
,
“HY”
and
“HZ”
in the case of a rectangular chamber:
“TESTSTEMYÇ”
,
“ZC”
co-ordinates of the center in any plan X = X
0
.
“HY”
,
“HZ”
dimensions of
sides of the chamber parallel respectively with the directions
Y
and
Z
.
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Titrate:
Operator
DEFI_FLUI_STRU
Date:
31/01/06
Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
10/20
Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
VALE_PAROI = l_vale
List realities giving the values of the geometrical characteristics, in correspondence
with the list of the names received for
CARA_PAROI
.
ANGL_VRIL = alpha
Swing angle (in degrees) around the directing axis of the beam for a chamber
rectangular. This operand is obligatory if one defines a rectangular chamber by
CARA_PAROI
and
VALE_PAROI
. It is prohibited in the case of a circular chamber.
Note:
Operands
CARA_PAROI
and
VALE_PAROI
are obligatory when the study carries
on the complete beam. When the study is based on a simplified representation,
these operands must appear together in at least one of the occurrences of
key word factor
FAISCEAU_AXIAL
. The operand
ANGL_VRIL
must also be
present under the same occurrence if a rectangular chamber is defined.
Example:
Total reference mark
(
)
X y Z
,
beam axis
y
HY
TESTSTEMYÇ
ZC
HZ
Z
X
alpha
Note:
If the study is carried out with the taking into account of the grids of the beam
tubes, the user must inform each of the eight operands which follow. One
recall that the geometry of a grid is a prismatic network at square base.
It can exist several types of grid; for example, grids of end and them
grids of mixture in the fuel assemblies. Grids of the same type
are characterized by identical dimensions and coefficients.
LONG_TYPG = l_hg
List realities giving the lengths of each type of grid of the beam of tubes.
length of a grid is its dimension according to the direction of the beam.
LARG_TYPG = l_dg
List realities giving the widths of each type of grid. The width of a grid is its
dimension in the plan perpendicular to the beam axis (i.e. the length of
dimensioned network).
EPAIS_TYPG = l_tg
List realities giving the thicknesses of each type of grid. What is called
thickness of grid, it is the thickness of the network constituting the grid in a section
perpendicular with the beam axis.
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Titrate:
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DEFI_FLUI_STRU
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A. ADOBES
Key
:
U4.25.01-G1
Page:
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
Example of grid:
Total reference mark
(
)
X y Z
,
beam axis
y
y
roast
dg
Hg
tg
RUGO_TYPG = l_rugg
List realities giving the height of roughness of each type of grid. These roughnesses
are used for the estimate of the coefficient of axial friction of each grid.
COEF_TRAI_TYPG = l_cdg
List realities giving the coefficient of drag of each type of grid. These coefficients
of drag allow to calculate the efforts of drag exerted by each grid on
the axial flow of the fluid.
COEF_DPOR_TYPG = l_cpg
List realities giving the slope (with null angle of attack) of the coefficient of lift of each
type of grid, which one supposes slightly tilted. These coefficients allow
to calculate the efforts of lift exerted by each grid on the flow of the fluid.
COOR_GRILL = l_zg
List co-ordinates “y” (along the beam axis) of the points of discretization of
each grid. These co-ordinates correspond to the points mediums (with mid- length)
grids.
TYPE_GRILL = l_itypg
List entireties defining the type of each grid.
3.4 Key word
COQUE_COAX
/COQUE_COAX
Key word factor allowing to characterize a configuration made up of two hulls
cylindrical coaxial separated by an annular play in which a fluid [bib2] runs out.
MASS_AJOU = “YES”
or
“NOT”
Indicator of the text type
[TXM]
by which the user specifies the taking into account or not
effects of added mass, in addition to the effects of added damping and stiffness.
GROUP_MA_INT = gr_ma_i
Identifier of the group of meshs (concept of the type
[group_ma]
) corresponding to
internal hull.
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Titrate:
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DEFI_FLUI_STRU
Date:
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Author (S):
A. ADOBES
Key
:
U4.25.01-G1
Page:
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
GROUP_MA_EXT = gr_ma_e
Identifier of the group of meshs (concept of the type
[group_ma]
) corresponding to
external hull.
VECT_X = l_comp
List of three realities giving the components of the directing vector of the axis of revolution
of the two hulls in the total reference mark. The axis of revolution of the hulls having to be one
axes of the total reference mark, only three sets of components are acceptable: (1., 0., 0.) ,
(0., 1., 0.) or (0., 0., 1.).
CARA_ELEM = will cara
Concept of the type
[cara_elem]
bringing all the geometrical characteristics of
elements.
MATER_INT = mater_i
Concept of the type
[to subdue]
bringing all the physical sizes characteristic of
material constitutive of the internal structure.
MATER_EXT = mater_e
Concept of the type
[to subdue]
bringing all the physical sizes characteristic of
material constitutive of the external structure.
RHO_FLUI = rho_f
Density of the fluid.
VISC_CINE = visco
Kinematic viscosity of the fluid.
ROUGHNESS = rug
Absolute roughness of wall of the hulls. A characteristic value for a smooth steel is
10
­ 5
measure.
PDC_MOY_1 = cde
Stationary part (average) of the singular loss ratio of load of input.
PDC_DYN_1 = cdep
Non stationary part (dynamic) of the singular loss ratio of load of input.
PDC_MOY_2 = cds
Stationary part (average) of the singular loss ratio of load of exit.
PDC_DYN_2 = cdsp
Non stationary part (dynamic) of the singular loss ratio of load of exit.
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Titrate:
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DEFI_FLUI_STRU
Date:
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A. ADOBES
Key
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Page:
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
Note:
1)
Values of the various average singular loss ratios of load and
dynamic are given, in complements, for various configurations
geometrical usual of input and exit (see hereafter [§6]).
2) By convention, a mean velocity of flow positive means that
the flow is done in the direction growing of the parameter of space along the axis
of revolution of the structures. Contrary, a mean velocity of flow
negative means that the flow is done in the direction decreasing of the parameter
of space. The sign mean velocity of flow thus fixes the positions
of input and exit. So that there is no ambiguity on these positions, one will take care
in
CALC_FLUI_STRU
[U4.80.03] to define a range of the same speeds signs.
3)
Model MOCCA_COQUE used for the resolution of the coupling fluid-structure
require, for each mode selected, to identify the command of hull on the deformation.
Commands of hull
K
I
identifiable are such as:
I
K
NR
2
where NR indicates it
a number of nodes of the mesh on a circumference, i.e at a fixed altitude.
commands of hull
K
I
precisely identified are such as
I
K
NR
4
, with the same one
definition for
NR
.
One advises to use a mesh with at least 20 nodes on the circumferences
hulls. A minimum number of 8 nodes is necessary.

3.5 Key word
INFORMATION
INFORMATION = 1
or
2
Level of impression.
If
INFORMATION
= 2 one prints the characteristics of the configuration in the file
MESSAGE
.
If
INFORMATION
= 1 pitch of impression.
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Titrate:
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Key
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
4 Complements concerning the configurations of the type
“beams of tubes under transverse flow”
4.1
Definition of the characteristics of the beam
Four operands
TYPE_PAS
,
TYPE_RESEAU
,
NOT
and
COEF_MASS_AJOU
are optional. None
value is not taken by defect. At the time of the definition of these characteristics, three use potential
are offered:
·
TYPE_PAS
,
TYPE_RESEAU
and
NOT
are present.
COUPLING = “YES”
The forces fluid-rubber bands will be taken into account during a dynamic calculation. The coefficient of
mass added is calculated according to the pitch and of the type of pitch.
·
TYPE_PAS
,
TYPE_RESEAU
,
NOT
and
COEF_MASS_AJOU
are present.
COUPLING = “YES”
The forces fluid-rubber bands will be taken into account during a dynamic calculation. The coefficient of
mass added is defined by the user.
·
COEF_MASS_AJOU
is present.
COUPLING = “NOT”
Only the added mass due to the fluid is taken into account (not coupling).

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5
Complements concerning the configurations “hulls
cylindrical coaxial "
One provides hereafter the values of the singular loss ratios of load for some
particular geometrical configurations of input-output.
5.1
Singular loss ratios of load of input

Configuration (1)
cde = 0,5
cdep = 0
Hull
intern
Hull
external
Z
0
R


H
1
Configuration (2)
cde
0,5
=
-




1 R H
R H
2
2
1
1
cdep = 0
R
1
R
2
H
2
0
R
Z
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DEFI_FLUI_STRU
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Instruction manual
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Configuration (3)
cde = 0
cdep = 0
R
Z


R
1
Configuration (4)
cde
=
-






=
-




1 R H
R H
R H
R H
R H
R H
1
1
2
2
2
2
1
1
2
2
1
1
2
2
2
1
cdep = 0
H
1
R
H
2
R
2
Z
0
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Key
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Page:
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Instruction manual
U4.2- booklet: Mesh HT-62/06/004/A
Configuration (5)
cde 0,5
cdep
cde
=
-




=
1 R H
R H
H
2
2
1
1
1
R
H
2
R
1
H
1
R
2
0
Z

5.2
Singular loss ratios of load of exit

Configuration (1)
cds = 1
cdsp = 0
Hull
external
Hull
intern
L
Z
R
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H
2
Configuration (2)
cds
=
-




1 R H
R H
2
2
3
3
2
cdsp = 0
R
H
3
R
3
Z
L
R
2


Configuration (3)
cds = 0
cdsp = 0
R
Z
L

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H
2
R
2
Configuration (4)
cds
0,5
=
-






1 R H
R H
R H
R H
3
3
2
2
2
2
3
3
2
cdsp = 0
R
H
3
R
3
Z
L


L
H
3
H
2
R
2
Configuration (5)
cds
cdsp
cds
=
-




= -
1 R H
R H
2
H
2
2
3
3
2
3
R
R
3
Z
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U4.2- booklet: Mesh HT-62/06/004/A
6 Bibliography
[1]
NR. GAY: Flustru Version 2.0 - general Presentation. Note of use - source FORTRAN of
software. Note technical EDF/DER HT-32/93.05A.
[2]
L. PEROTIN, Mr. LAINET: Integration of various models of excitations fluid-rubber bands
in Code_Aster: specifications HT-32/96/014/A.