v3.04.004 SSLV04 - Hollow cylinder with plane stresses#

Summary:

This test is taken from Guide VPCS (test SSLV04 /89) and its object is a hollow cylinder loaded with internal pressure.

This three-dimensional problem is treated with various models:

  • in \(3D\): 9 models (pentahedra, hexahedra, tetrahedra and pyramids, degrees 1 and 2),

  • in \(2D\) plane constraints: 4 models (triangles and quadrangles degrees 1 and 2, quadrangles with 9 knots),

  • in \(2D\) axisymmetric: 3 models (triangles and quadrangles degrees 1 and 2, quadrangles with 9 knots).

The tested functionalities are:

  • distributed pressure,

  • shape effect (with fixed or variable pressure),

  • mandatory trips,

  • stiffness matrices,

  • deformations and stresses at the nodes,

  • nodal reactions (K modeling),

  • use of MACR_LIGN_COUP on a mult_elas concept and a comb_fourier concept

(modeling I)

There are 16 models.

Reference Issue

Geometry

Coordinates of the points:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

0.100

0.200

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

0

Material Properties

The Young’s modulus of the material is equal to \(>\).

The Poisson’s ratio is equal to \(>\).

Boundary conditions and loads

Internal pressure:

\(>\)

Variable internal pressure (P modeling only):

\(>\) varies linearly from \(>\) to \(>\) to \(>\) to \(>\)

Reference solution

Calculation method used for the reference solution

In plane stress (cylinder with free edges at the ends)

\(>\)

We get:

for \(>\): \(>\); for \(>\): \(>\)

Transition to the Cartesian axis system:

\(>\)

with:

  • \(>\) in points \(>\) and \(>\),

  • \(>\) in points \(>\) and \(>\),

  • \(>\) at points \(>\) and \(>\).

Benchmark Results

Displacements \(>\) and constraints \(>\) at points \(>\).

Bibliographical references

  1. Guide VPCS. SSLV04 /89

  2. Y.C. FUNG. Foundations of solid mechanics. Prentice-hall, Inc. Englewood Cliffs. NJ. 1965 p.243-245.

    1. COURBON. Material strength p 649

Modeling A

Modelling characteristics

3D elements (PENTA6 and HEXA8).

Mesh obtained by extrusion from a \(>\) mesh similar to the mesh below (30 elements in the radial direction with gradual de-refinement and \(>\) elements in the circumferential direction).

+———————————+——————————-+——————-+———+———+———++++ |Following axis :math:`>`: |1 layer of elements | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ |Total thickness: |:math:`>` | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ | | | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ |Boundary conditions: | | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ | | | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ |Bow :math:`>`: :math:`>` | | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ |Face :math:`>` stuck in :math:`>` | | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ | |Face :math:`>` blocked normally | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ |Pressure on the face :math:`>` |:math:`>` | | +---------------------------------+-------------------------------+-------------------+---------+---------+---------++++ | | | | | || +———————————+——————————-+——————-+———+———+———++++ |Node names: |:math:`>`|\(>`|:math:\)>`| || +———————————+——————————-+——————-+———+———+———++++ | |:math:`>`|\(>`|:math:\)>`| || +———————————+——————————-+——————-+———+———+———++++

Mesh characteristics

Number of knots: 1922

Number of meshes and types: 900 PENTA6, 450 HEXA8 and 90 QUAD4 (inner skin sides).

Tested quantities and results

Location

Size

Reference

Reference Type

Tolerance

Field nor_ DNOR Point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

1.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

0.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

B Modeling

Modelling characteristics

3D elements (PENTA15 and HEXA20).

Mesh obtained by extrusion from mesh \(>\) below (F modeling)

+———————————+——————————-+——————–++ |Following axis :math:`>`: |2 layers of elements|| +———————————+——————————-+——————–++ |Total thickness: |:math:`>` || +———————————+——————————-+——————–++ | | || +———————————+——————————-+——————–++ |Boundary conditions: | || +———————————+——————————-+——————–++ | | || +———————————+——————————-+——————–++ |Bow :math:`>` | || +———————————+——————————-+——————–++ |Face :math:`>` stuck in :math:`>` | || +———————————+——————————-+——————–++ | |Face :math:`>` blocked normally | +---------------------------------+-------------------------------+--------------------++ |Pressure on the face :math:`>` |:math:`>` || +———————————+——————————-+——————–++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 2115

Number of meshes and types: 400 PENTA15, 100 HEXA20, 100, 40 QUAD8 (inner skin sides)

Tested quantities and results

Location

Size

Reference

Reference Type

Tolerance

Mesh MA751, point \(>\)

SIRO_ELEM

\(>\)

0.0

“ANALYTIQUE”

Normal stress at element face

\(>\)

60.0

“ANALYTIQUE”

0.5%

\(>\)

0.0

“ANALYTIQUE”

0.01

SIRO_ELEM

\(>\)

0.0

“ANALYTIQUE”

0.1

Tangential stress in the element plane

\(>\)

0.0

“ANALYTIQUE”

0.1

\(>\)

0.0

“ANALYTIQUE”

0.1

SIRO_ELEM

\(>\)

0.0

“ANALYTIQUE”

0.01

First constraint value

\(>\)

0.0

“ANALYTIQUE”

“”

0.01

tangential in the element plane

\(>\)

0.0

“ANALYTIQUE”

“”

0.05

SIRO_ELEM

\(>\)

100.0

“ANALYTIQUE”

0.15%

Second constraint value

\(>\)

0.0

“ANALYTIQUE”

“”

4.5

tangential in the element plane

\(>\)

0.0

“ANALYTIQUE”

“”

0.20

“ANALYTIQUE”

Mesh MA769, point \(>\)

“ANALYTIQUE”

SIRO_ELEM

\(>\)

-42.426

“ANALYTIQUE”

6.0%

Normal stress at element face

\(>\)

42.426

“ANALYTIQUE”

4.0%

\(>\)

0.0

“ANALYTIQUE”

0.01

SIRO_ELEM

\(>\)

0.0

“ANALYTIQUE”

0.01

Tangential stress in the element plane

\(>\)

0.0

“ANALYTIQUE”

0.01

\(>\)

0.0

“ANALYTIQUE”

0.03

SIRO_ELEM

\(>\)

0.0

“ANALYTIQUE”

0.01

First constraint value

\(>\)

0.0

“ANALYTIQUE”

“”

0.01

tangential in the element plane

\(>\)

0.0

“ANALYTIQUE”

0.01

SIRO_ELEM

\(>\)

70.711

“ANALYTIQUE”

3.5%

Second constraint value

\(>\)

70.711

“ANALYTIQUE”

4.5%

tangential in the element plane

\(>\)

0.0

“ANALYTIQUE”

“”

0.1

C Modeling

Modelling characteristics

3D elements (TETRA4).

\(>\) is on the \(>\) axis

+———————————+——————————-+——————————————————————–++ |Die-cutting: |21 equidistant nodes on segments :math:`>`, :math:`>`, and :math:`>`|| +———————————+——————————-+——————————————————————–++ | |21 knots equidistant on arcs :math:`>` and :math:`>` || +———————————+——————————-+——————————————————————–++ | | || +———————————+——————————-+——————————————————————–++ |Following axis :math:`>`: |1 layer of elements || +———————————+——————————-+——————————————————————–++ |Total thickness: |:math:`>` || +———————————+——————————-+——————————————————————–++ | | || +———————————+——————————-+——————————————————————–++ |Boundary conditions: | || +———————————+——————————-+——————————————————————–++ | | || +———————————+——————————-+——————————————————————–++ |Bow :math:`>`: :math:`>` | || +———————————+——————————-+——————————————————————–++ |Face :math:`>` stuck in :math:`>` | || +———————————+——————————-+——————————————————————–++ | |Face :math:`>` blocked normally | +---------------------------------+-------------------------------+--------------------------------------------------------------------++ |Pressure on the face :math:`>` |:math:`>` || +———————————+——————————-+——————————————————————–++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 1115

Number of meshes and types: 3724 TETRA4 and 1760 TRIA3 (inner skin sides)

Tested quantities and results

Location

Size

Reference Value

Reference Type

Tolerance

Field nor_ DNOR Point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

1.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

0.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

D Modeling

Modelling characteristics

3D element (TETRA10).

\(>\) is on the \(>\) axis

+———————————+——————————-+——————————————————————-++ |Die-cutting: |11 equidistant nodes on segments :math:`>`, :math:`>` and :math:`>`|| +———————————+——————————-+——————————————————————-++ | |11 knots equidistant on arcs :math:`>` and :math:`>` || +———————————+——————————-+——————————————————————-++ | | || +———————————+——————————-+——————————————————————-++ |Following axis :math:`>`: |1 layer of elements || +———————————+——————————-+——————————————————————-++ |Total thickness: |:math:`>` || +———————————+——————————-+——————————————————————-++ | | || +———————————+——————————-+——————————————————————-++ |Boundary conditions: | || +———————————+——————————-+——————————————————————-++ | | || +———————————+——————————-+——————————————————————-++ |Bow :math:`>`: :math:`>` | || +———————————+——————————-+——————————————————————-++ |Face :math:`>` stuck in :math:`>` | || +———————————+——————————-+——————————————————————-++ | |Face :math:`>` blocked normally | +---------------------------------+-------------------------------+-------------------------------------------------------------------++ |Pressure on the face :math:`>` |:math:`>` || +———————————+——————————-+——————————————————————-++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 1395

Number of meshes and types: 652 TETRA10 and 480 TRIA6 (inner skin sides)

Tested quantities and results

E Modeling

Modelling characteristics

Elements C_PLAN (TRIA3 + QUAD4)

Mesh \(>\) similar to the mesh below (30 elements in the radial direction with gradual deraffination and \(>\) elements in the circumferential direction).

Boundary conditions:

+———————————+——————————+++ |Side :math:`>` stuck in :math:`>` ||| +———————————+——————————+++ | |side :math:`>` locked normally | +---------------------------------+------------------------------+++ |Pressure on :math:`>` :math:`>` ||| +———————————+——————————+++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 961

Number of meshes and types: 900 TRIA3, 450 QUAD4

Tested quantities and results

Location

Size

Reference Values

Reference Type

Tolerance

Field nor_ DNOR Point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ DNOR point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

0.1%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

1.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

0.0

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

Field nor_ PRES point \(>\)

Normal vector, component \(>\)

-0.707

“ANALYTIQUE”

1.5%

F Modeling

Modelling characteristics

Elements C_Plan **** (**** QUAD8 **** **+** TRIA6 ****) **

Boundary conditions:

side \(>\) stuck in \(>\)

side \(>\) locked normally

press on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 591

Number of meshes and types: 200 TRIA6, 50 QUAD8

Tested quantities and results

Modelling characteristics

Modeling C_PLAN **** (**** QUAD9 **** )

Boundary conditions:

side \(>\) stuck in \(>\)

side \(>\) locked normally

pressure on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 441

Number of meshes and types: 100 QUAD9

Tested quantities and results

Modelling characteristics

Elements AXIS **** (**** TRIA3 + QUAD4 **** )

Boundary conditions:

node \(>\) stuck in \(>\) press on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 113

Number of meshes and types: 40 QUAD4, 80 TRIA3

Tested quantities and results

Modeling I

Modelling characteristics

Elements AXIS **** (**** TRIA6 **** + QUAD8 )

Boundary conditions:

Node \(>\) stuck in \(>\) press on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 175

Number of meshes and types: 20 QUAD8, 40 TRIA6

Tested quantities and results

Results from MACR_LIGN_COUP on the AE segment:

The NON_REGRESSION tests are done on the tables from MACR_LIGN_COUP applied to a CHAMP_GD. They are the “AUTRE_ASTER” reference values for tables from MACR_LIGN_COUP applied to a mult_elas result.

Location

Size

Reference value

Reference type

Precision

Point

ABSC_CUR

Field

Component

\(>\)

0000

DEPL

DX

“NON_REGRESSION”

\(>\)

0.005

DEPL

DX

“NON_REGRESSION”

\(>\)

0.1

DEPL

DX

NON_REGRESSION “

\(>\)

0000

DEPL

DX

1.35511346318

“AUTRE_ASTER”

\(>\)

0.005

DEPL

DX

1.35531703991

“AUTRE_ASTER”

\(>\)

0.1

DEPL

DX

1.35511346318

“AUTRE_ASTER”

The same procedure is used to test the result of MACR_LIGNE_COUPE applied to a comb_fourier concept.

Location

Size

Reference value

Reference type

Precision

Point

ABSC_CUR

Field

Component

\(>\)

0000

DEPL

DX

“NON_REGRESSION”

\(>\)

0.005

DEPL

DX

“NON_REGRESSION”

\(>\)

0.1

DEPL

DX

NON_REGRESSION “

\(>\)

0000

DEPL

DX

5.8999716105E-05

“AUTRE_ASTER”

\(>\)

0.005

DEPL

DX

5.90000189066E-05

“AUTRE_ASTER”

\(>\)

0.1

DEPL

DX

5.89997161037E-05

“AUTRE_ASTER”

J Modeling

Modelling characteristics

Elements AXIS **** (**** QUAD9 **** )

Boundary conditions:

node \(>\) stuck in \(>\) press on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 205

Number of meshes and types: 40 QUAD9

Tested quantities and results

Modelling characteristics

Elements 3D **** (**** PENTA6 **** **** and HEXA8 )

Mesh obtained by extrusion from mesh \(>\) below (modeling E)

+———————————————————–+——————————-+—————————————-++ |Following axis :math:`>`: |2 layers of elements || +———————————————————–+——————————-+—————————————-++ |Total thickness: |:math:`>` || +———————————————————–+——————————-+—————————————-++ | | || +———————————————————–+——————————-+—————————————-++ |Boundary conditions: | || +———————————————————–+——————————-+—————————————-++ | | || +———————————————————–+——————————-+—————————————-++ |Node :math:`>`: :math:`>` face :math:`>` stuck in :math:`>` | || +———————————————————–+——————————-+—————————————-++ | |Face :math:`>` blocked normally | +-----------------------------------------------------------+-------------------------------+----------------------------------------++ |Face :math:`>` |radial displacement imposed on :math:`>`|| +———————————————————–+——————————-+—————————————-++

Node names:

\(>\)

\(>\)

\(>\)

plan \(>\)

\(>\)

\(>\)

\(>\)

plan \(>\)

\(>\)

\(>\)

\(>\)

Node names:

\(>\)

\(>\)

\(>\)

plan \(>\)

\(>\)

\(>\)

\(>\)

plan \(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 513

Number of meshes and types: 400 PENTA6, 100 HEXA8, 100, 40 QUAD4 (inner skin sides)

Remarks

In this case, the load is in forced displacement, unlike other models. We are testing the reactions.

Tested quantities and results

Location

Size

Reference Value

Reference Type

Tolerance

\(>\)

Field REAC_NODA, comp FX

1.0884 E—3

“AUTRE_ASTER”

0.7%

Field REAC_NODA, comp FY

4.5084 E—4

“AUTRE_ASTER”

1.7%

\(>\)

Field REAC_NODA, comp FX

2.1768 E—3

“AUTRE_ASTER”

1%

Field REAC_NODA, comp FY

9.0170 E—4

“AUTRE_ASTER”

1.3%

\(>\)

Field REAC_NODA, comp FX

1.0884 E—3

“AUTRE_ASTER”

0.7%

Field REAC_NODA, comp FY

4.5084 E—4

“AUTRE_ASTER”

1.7%

\(>\)

Field REAC_NODA, comp FX

1.1636 E—3

“AUTRE_ASTER”

0.7%

Field REAC_NODA, comp FY

1.8429 E—4

“AUTRE_ASTER”

0.6%

\(>\)

Field REAC_NODA, comp FX

1.0045 E—3

“AUTRE_ASTER”

1%

Field REAC_NODA, comp FY

6.1550 E—4

“AUTRE_ASTER”

1%

\(>\)

Field REAC_NODA, comp FX

2.3272 E—3

“AUTRE_ASTER”

0.5%

Field REAC_NODA, comp FY

3.6858 E—4

“AUTRE_ASTER”

0.6%

\(>\)

Field REAC_NODA, comp FX

2.0090 E—3

“AUTRE_ASTER”

0.7%

Field REAC_NODA, comp FY

1.2310 E—3

“AUTRE_ASTER”

0.8%

Remarks

We check that the nodal forces of reactions are zero at all nodes, except on the nodes of surface \(>\) and surfaces \(>\) and \(>\).

L Modeling

Modelling characteristics

Elements 3D **** (**** PYRAM5 **** )

+———————————————————–+——————————-+———————————————-++ |Following axis :math:`>`: |each parallelepiped is divided into 6 pyramids|| +———————————————————–+——————————-+———————————————-++ |Total thickness: |:math:`>` || +———————————————————–+——————————-+———————————————-++ | | || +———————————————————–+——————————-+———————————————-++ |Boundary conditions: | || +———————————————————–+——————————-+———————————————-++ | | || +———————————————————–+——————————-+———————————————-++ |Node :math:`>`: :math:`>` face :math:`>` stuck in :math:`>` | || +———————————————————–+——————————-+———————————————-++ | |Face :math:`>` blocked normally | +-----------------------------------------------------------+-------------------------------+----------------------------------------------++ |Pressure on the face :math:`>` |:math:`>` || +———————————————————–+——————————-+———————————————-++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 342

Number of meshes and types: 600 PYRAM5 620 QUAD4 (inner skin sides)

Tested quantities and results

Modelling characteristics

Elements 3D **** (**** PYRAM13 **** )

+———————————————————–+——————————-+———————————————-++ |Following axis :math:`>`: |each parallelepiped is divided into 6 pyramids|| +———————————————————–+——————————-+———————————————-++ |Total thickness: |:math:`>` || +———————————————————–+——————————-+———————————————-++ | | || +———————————————————–+——————————-+———————————————-++ |Boundary conditions: | || +———————————————————–+——————————-+———————————————-++ | | || +———————————————————–+——————————-+———————————————-++ |Node :math:`>`: :math:`>` face :math:`>` stuck in :math:`>` | || +———————————————————–+——————————-+———————————————-++ | |Face :math:`>` blocked normally | +-----------------------------------------------------------+-------------------------------+----------------------------------------------++ |Pressure on the face :math:`>` |:math:`>` || +———————————————————–+——————————-+———————————————-++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 1703

Number of meshes and types: 600 PYRAM13 620 QUAD8 (inner skin sides)

Tested quantities and results

N Modeling

Modelling characteristics

Elements 3D **** (**** PENTA15 **** **** and HEXA20 )

Mesh obtained by extrusion from a \(>\) mesh similar to the mesh below (8 elements in the radial direction, \(>\) elements in the circumferential direction) and duplicated to have a complete section of the cylinder (over 360°).

+—————————————————————+———+——————-+———+———+++ |Following axis :math:`>`: |1 layer of elements | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |Total thickness: |:math:`>` | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ | | | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |Boundary conditions: | | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ | | | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |Face :math:`>` stuck in :math:`>` face :math:`>` stuck normally | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ | | | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |Pressure on the face :math:`>` |:math:`>` | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |shape effect on sections |:math:`>` | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ | | | +---------------------------------------------------------------+---------+-------------------+---------+---------+++ |Node names: |:math:`>` |:math:`>`|\(>`||| +---------------------------------------------------------------+---------+-------------------+---------+---------+++ | |:math:\)>` |:math:`>`|:math:`>`||| +—————————————————————+———+——————-+———+———+++

Mesh characteristics

Number of knots: 8832

Number of meshes and types: 1024 PENTA15, 512 HEXA20, 512, 1176 QUAD8 and 2048 TRIA6.

Remarks

Contrary to previous models, the background effect applying to the sections at the ends of the cylinder is taken into account here.

Tested quantities and results

O Modeling

Modelling characteristics

Elements C_PLAN **** (**** QUAD8 **** + TRIA6 )

Mesh \(>\) similar to the mesh below (8 elements in the radial direction, \(>\) elements in the circumferential direction) and duplicated to have a complete section of the cylinder (over 360°).

Boundary conditions:

side \(>\) stuck in \(>\)

side \(>\) locked normally

pressure on \(>\) \(>\)

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 3840

Number of meshes and types: 1026 TRIA6, 512 QUAD8

Tested quantities and results

P modelling

Modelling characteristics

Elements 3D (PENTA15 and **** HEXA20 **** ) — same mesh as N modelling

Mesh obtained by extrusion from a \(>\) mesh similar to the mesh below (8 elements in the radial direction, \(>\) elements in the circumferential direction) and duplicated to have a complete section of the cylinder (over 360°).

+—————————————————————————————————————-+——————————-+——————-++ |Following axis :math:`>`: |1 layer of elements|| +—————————————————————————————————————-+——————————-+——————-++ |Total thickness: |:math:`>` || +—————————————————————————————————————-+——————————-+——————-++ | | || +—————————————————————————————————————-+——————————-+——————-++ |Boundary conditions: | || +—————————————————————————————————————-+——————————-+——————-++ | | || +—————————————————————————————————————-+——————————-+——————-++ | |Face :math:`>` blocked normally | +----------------------------------------------------------------------------------------------------------------+-------------------------------+-------------------++ |Face :math:`>` stuck in :math:`>` | || +—————————————————————————————————————-+——————————-+——————-++ |Pressure on the face :math:`>` |:math:`>` || +—————————————————————————————————————-+——————————-+——————-++ |shape effect on sections |:math:`>` || +—————————————————————————————————————-+——————————-+——————-++ | | || +—————————————————————————————————————-+——————————-+——————-++ |With :math:`>`: pressure as a linear function of time equal to :math:`>` to :math:`>` and :math:`>` to :math:`>` || +—————————————————————————————————————-+——————————-+——————-++

Node names:

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

\(>\)

Mesh characteristics

Number of knots: 8832

Number of meshes and types: 1024 PENTA15, 512 HEXA20, 512, 1176 QUAD8 and 2048 TRIA6.

Remarks

Contrary to N modeling, here we test a pressure and a shape effect that vary as a function of time. A linear variation in pressure leads to a linear variation in stresses.

Tested quantities and results

Summary of results

Summary of max errors in %

3D

Location

mod A

mod A

mod B

mod D

mod L

mod M

mod M

mod N

mod P

elem

pe6, h8

pe15, h8

pe15, h20

te4

te10

py5

py13

pe15, h20

pe15, h20

pe15, h20

geom

45°

45°

45°

45°

45°

45°

360°

360°

360°

nb no

1922

2115

2115

1115

1395

342

1703

8832

8832

Depl.

A, E B, F

0.08 0.10

0.09 0.07

0.17 0.30

0.04 0.04

0.21 0.16

0.00 0.00

0.00 0.00

0.00 0.00

\(>\)

A, E B, F

4.59 5.24

0.39 0.07

10.45 7.78

4.41 0.95

11.74 5.24

0.11 0.11

1.64 0.09

1.64 0.09

\(>\)

A, E B, F

5.70 1.89

0.92 0.01

9.46 2.46

1.80 0.49

57.57 4.75

0.81 0.08

1.64 0.09

1.64 0.09

\(>\)

A, E B, F

Good Good

Good Good

Good Good

Good Good

Good Good

Good Good

0.87 0.04

0.87 0.04

\(>\)

A, E B, F

0.15 0.90

0.26 0.06

2.89 0.81

0.27 0.28

3.46 4.95

0.07 0.09

0.03 0.01

0.03 0.01

C_PLAN

Location

mod E

mod F

mod G

mod O

Type of elements

tria3, quad4

tria6, quad8

quad9

tria6, quad8

Modeled geometry

45°

45°

45°

45°

360°

Number of nodes

961

961

591

441

384

Travel

A, E B, F

0.07 0.09

0.09 0.07

0.00 0.00

0.01 0.00

Constraints \(>\)

A, E B, F

4.65 5.19

0.39 0.06

0.27 0.02

1.44 0.08

Constraints \(>\)

A, E B, F

5.68 1.40

0.90 0.04

0.16 0.05

1.44 0.08

Constraints \(>\)

A, E B, F

Good Good

Good Good

Good Good

Good Good

Constraints \(>\)

A, E B, F

0.16 1.23

0.23 0.07

0.20 0.09

0.10 0.00

AXIS

Location

mod H

mod I

mod J

Type of elements

tria3, quad4

tria6, quad8

quad9

Number of nodes

113

113

175

205

Travel

A, E B, F

0.01 0.01

0.00 0.00

0.00 0.00

Constraints \(>\)

A, E B, F

5.66 Good

0.17 Good

0.17 Good

Constraints \(>\)

A, E B, F

Good Good

Good Good

Good Good

Constraints \(>\)

A, E B, F

1.29 1.00

0.09 0.07

0.09 0.02

Constraints \(>\)

A, E B, F

Good Good

Good Good

Good Good

  • The results are more accurate with items of order 2.

  • The problem is more suited to axisymmetric modeling. The results are better.

  • The meshes remain insufficient for 3D elements of order 1: constraints and deformations of the A, C, E and L models (especially for the L modeling in PYRAM5).

  • Pyramids give results similar to other 3D elements, with equivalent meshes.

  • N and P models with constant or variable shape effect and pressure give good results.