Creating 1D elements on given component with given cross-section and DOF
OBJECTIVE:
To create 1D elements on given component with given cross-section and DOF.
THEORY:
1) HyperWorks - HyperWorks is a complete CAE software made by Altair engineering. It consists all the modules of CAE i.e. modelling, meshing, solver. It is a complete package of finite element procedure. Preprocessing, Solving and Postprocessing can be done using Hyperworks. Other than Hypermesh, HyperWorks also includes OptiStruct, RADIOSS, MotionView, MotionSolve, FEKO, etc.
2) Hypermesh - Hypermesh is an inbuilt meshing software which comes along with Hyperworks. It is a meshing tool. It can also be used to model simple geometries, and its most important function is meshing. Meshing is an important process in finite element method. The accuracy of the solution depends upon the type of mesh you choose and the complexity of the problem.
3) Finite Element Analysis (FEA) - The process of dividing or discretizing our geometry into finite nodes and elements and solving it for stress and strains is known as FEA.
4) Meshing - The particular process of discretization used in FEA is known as meshing.
5) Rigids - Rigids are also known as RBE2 elements. They have infinite stiffness. They never bends, rotate or move. Only the nodes can move in rigids. In RBE2, the load distribution is uniform irrespective of the position from the load.
6) RBE3 - In RBE3, the load distribution depends on the distance from the load. Load distribution is more on the nodes closer to the load.
7) Rods - Rods are used for compression and tension. But sometimes they are used for rotation as well (limited).
8) Bars - In bars, all the 6 dofs are used and they are used for symmetrical sections.
9) Beams - Beams are similar to bars but also used for asymmetrical sections also.
SPECIFICATIONS:
a.
Rod element:- with only translational DOF and RBE2 link
Cross-Section: BOX- Dimension a= 12 mm
dimension b=10 mm
Thickness t= 0.75 mm
b. Beam element:- with all DOF and RBE3 link
Cross-Section: I Section- Dimension a= 8 mm
Dimension b= 10 mm
Dimension c= 8.5 mm
Thickness t1= 0.75 mm
Thickness t2= .6 mm
Thickness t3= .6 mm
c. Bar element:- with only x and y DOFs With RBE3 link
Cross-section: CROSS section- Dimension DIM1= 5 mm
Thickness DIM2= 1.2 mm
Dimension DIM3= 10 mm
Thickness DIM4= 1.2mm
d. & e. apply the mass of magnitude 10 with RBE2 link
f. Join the two components with Spring elements
PROCEDURE:
I. Importing geometry
File-Import-Geometry-(Select file)-Import
II. Extracting midsurface and deleting solid part
Step 1: Extracting midsurface
Geom-midsurface-(Select the surface)-extract
(Here rename the component as 'Bracket_1')
Step 2: Create a new component
(Right-click) Component-create
(Here rename as 'Bracket_2')
Step 3: Deleting the solid part and wireframe
Step 4: Moving one midsurface to 'Bracket_2'
Tool-organize-(Select the surface)-Give dest component="Bracket_2"
Step 5: Changing colour
III. Meshing the brackets
Step 1: Creating washer split
Geom-quick edit-Give offset value='5'-(Select the lines)
Step 2: Meshing each bracket
2D-automesh-(Select the surface)-Give element size='8'-mesh
V. Creating material
(Right-click on the model tree) Create-material
Give material name as "Steel".
Give E='210000', Nu='0.3'
VI. Creating properties
(Right-click on the model tree) Create-Property
We have to create properties for 'Bracket_1', 'Bracket_2', 'Rod', 'Beam', 'Bar' and spring
Give card image based on the property as given below:
| SERIAL NO. |
PROPERTY |
CARD IMAGE |
| 1 |
Bracket_1 |
PSHELL |
| 2 |
Bracket_2 |
PSHELL |
| 3 |
Rod |
PROD |
| 4 |
Beam |
PBEAM |
| 5 |
Bar |
PBAR |
| 6 |
Spring |
PBUSH |
VII. Creating rod, beam, bar and mass elements
a) Creating rod
Step 1: Creating RBE2 link
1D-rigids-(Select the nodes)-Uncheck 'dof1', 'dof2' & 'dof3'-create
Step 2 : Creating rod
1D-rods(Select the nodes)-Give property='Rod'
b) Creating beam
Step 1: Creating RBE3 link
1D-rbe3-(Select the nodes)-Uncheck all the dofs-create
Step 2: Creating beam
1D-bar-(Select the nodes)-Give property='Beam' and elem type='CBEAM'-Give the orientation
c) Creating bar
Step1: Creating RBE3 link
1D-rbe3-(Select the nodes)-Uncheck 'dof1', 'dof2','dof4' and 'dof5'
Step 2: Creating bar
1D-bar-(Select the nodes)-Give property='Bar' and elem type='CBAR'-Give the orientation
d) Creating masses
Step 1: Creating RBE2 link
1D-rigids-(Select the nodes)-create
Step 2: Creating mass
1D-masses-Give magnitude='10'-Give elem type='CMASS1'-Give property='Bracket_1' or 'Bracket_2'-create
VIII. Creating springs
1D-springs-(Select the nodes)-Give property='Spring' and elem type='CELAS1'
IX. Creating cross-section
1D-Hyperbeam-Select 'Standard section' (from left options)-Select 'HYPERBEAM' (from standard section library)-create
a) Creating box cross section
a= 12 mm
dimension b=10 mm
Thickness t= 0.75 mm
b) Creating I section
Dimension a= 8 mm
Dimension b= 10 mm
Dimension c= 8.5 mm
Thickness t1= 0.75 mm
Thickness t2= .6 mm
Thickness t3= .6 mm
c) Creating cross section
Dimension DIM1= 5 mm
Thickness DIM2= 1.2 mm
Dimension DIM3= 10 mm
Thickness DIM4= 1.2mm
X. Assigning cross-section to components
(Select components one by one)-Specify the correct beam section for each.
RESULT:
1)The geometry was imported and meshed.
2)1D elements were created on the given component with given cross-section and DOF.
