Difference between revisions of "Contrib:KeesWouters/shell/static"

Revision as of 17:21, 7 March 2010 (view source) Brigde (Talk | contribs) (→‎'''displacements''') ← Older edit		Revision as of 17:49, 7 March 2010 (view source) Keeswouters (Talk | contribs) m (→‎''Partitioning of the geometry'') Newer edit →
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	===''Partitioning of the geometry''===		===''Partitioning of the geometry''===
−	why: we need groups for loads and boundary conditions<br>	+	Why: we need groups for loads and boundary conditions. Partitioning the original geometry makes sure that the resulting mesh each group is meshed along its borders correctly and the mesh is connected between the groups<br/>
−	how: we define planes<br>	+	How: the geometry is divided by planes or 2D surfaces. These ''Tool objects'' need to divide the geometry completely in two seperate parts. In Salome several ''Tool objects'' can be choosen in one Partition operation.<br/>
	'''Create partition''' ''[Operations]->[Partition]'' <br>		'''Create partition''' ''[Operations]->[Partition]'' <br>

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Revision as of 17:49, 7 March 2010

Static analysis of a shell construction

[ .... under construction .... ]

This contribution is in close cooperation with Bridge.

In this example the following items are discussed:

• preproccesing:
• definition of geometry in Salome
• partitioning of the geometry and groups
• meshing of the geometry
• definition of the groups
• (maybe: python script which makes editing much easier ...)

• static analysis with pressure or force applied on a group or nodes

• postprocessing:
• viewing displacement in Salome
• determination of stresses

• interface ASTK

Definition of the geometry

planar shell Geometry:

• L = 11.38 m
  
• Thickness = 0.55 m
  

Loads:
[type] [group] [value]

• Presure1 (Fbot) = 29.5e3 Pa
  
• Presure2 (Fmain)= 25.8e3 Pa
  
• Presure3 (Ftop) = 24.3e3 Pa
  
• Presure4 (Fcentre1,Fcentre2)= 182.6e3 Pa
  

Boundary conditions:

• Lbot (DX=0.0, DY=0.0, DZ=0.0)
  
• Ltop (DZ=0.0)
  

Material:
Concrete

• E = 32e9 Pa
  
• Nu = 0.2
  

---

Create all points and lines using: [New Entity]->[Basic}->[Point] and [New Entity]->[Basic]->[Line]
 :

The coordinates are:

P1 = geompy.MakeVertex(  0.000,  0.00, 0.00) 
P2 = geompy.MakeVertex( 11.380,  0.00, 0.00)
P3 = geompy.MakeVertex(  0.433,  2.25, 0.00)
P4 = geompy.MakeVertex( 11.813,  2.25, 0.00)
P5 = geompy.MakeVertex(  1.875,  9.75, 0.00)
P6 = geompy.MakeVertex( 13.255,  9.75, 0.00)
P7 = geompy.MakeVertex(  2.010, 10.45, 0.00)
P8 = geompy.MakeVertex( 13.390, 10.45, 0.00)

P9 = geompy.MakeVertex(  5.300,  5.72, 0.00)
P10 = geompy.MakeVertex( 5.300,  7.05, 0.00)
P11 = geompy.MakeVertex( 9.830,  5.72, 0.00)
P12 = geompy.MakeVertex( 9.830,  7.05, 0.00)
P13 = geompy.MakeVertex( 5.300,  8.42, 0.00)
P14 = geompy.MakeVertex( 5.300,  9.75, 0.00)
P15 = geompy.MakeVertex( 9.830,  8.42, 0.00)
P16 = geompy.MakeVertex( 9.830,  9.75, 0.00)

---

Create one big face Ftotal [New Entity]->[Build]->[Face]
Ftotal: Line7,Line6,Line8,Line12,Line11,Line10,Line9,Line1

---

Create three wires [New Entity]->[Build]->[Wire]

• Wire1: Line3,Line4,Line5
  
• Wire2: Line17,Line18,Line19
  
• Wire3: Line13,Line14,Line15,Line16
  

---

Create vector [New Entity]->[Basic]->[Vector]
(0,0,1)
Create four extrusions [New Entity]->[Generation]->[Extrusion]

• Extrusion1: Wire1,vz
  
• Extrusion2: Wire2,vz
  
• Extrusion3: Wire3,vz
  
• Extrusion4: Line2,vz
  

---

Partitioning of the geometry

Why: we need groups for loads and boundary conditions. Partitioning the original geometry makes sure that the resulting mesh each group is meshed along its borders correctly and the mesh is connected between the groups
How: the geometry is divided by planes or 2D surfaces. These Tool objects need to divide the geometry completely in two seperate parts. In Salome several Tool objects can be choosen in one Partition operation.

Create partition [Operations]->[Partition]

• Part_main: Ftotal,Extrusion1,Extrusion2,Extrusion3,Extrusion4
  

Create two groups for boundary conditions [New Entity]->[Group]->[Create]
Shape type: line
Main Shape: Part_main

• Lleft: left lines: Line7,Line8,Line9
• Lright: right lines: Line10,Line11,Line12

Meshing

how
tria -quad?
linear vs quadratic elements

---

Triangle mesh

Set Mesh 1D: Composite Side discretisation


Set Mesh 1D Average lenght: 0,5


Mesh 2D settings: Netgen 2d


Mesh info:


Computed Mesh:


Convert to quad mesh

ASTK - Aster

Shell6.comm.zip http://www.caelinux.org/wiki/images/e/e4/Shell6.comm.zip - obsolete: bad bc

Postprocessing

displacements

local stresses

equivalent stresses