Challenge

Week 4- Challenge

Objective:Creat 1D elements on the following component with given cross-section and DOF.

Procedure:

Import the geometry in hypermesh.
Make sure that geometry is clear for any edges and pin holes.
Now extract the midsurface Geometry-midsurface-extract.
Create seperate componenet for each bracket i.e. bracket 1 and bracket 2.
Now organize the midsurface to each component as created above.
Now as the meshing geometry is symmetrical split the surface horizontally or vertically.
In this case I have split the surface horizontally.
Around the holes use washer split for better meshing.
Now mesh the geometry 2D-Automesh-select surface-set element size 10-Mesh.
After meshing adjust the element quantity manually for better mesh flow.
As meshing is done on half spiltted surface reflect the entire mesh to other half of geometry.
For reflect got to tools-reflect-select elements-duplicate-select direction and base point and hit reflect.
Now go to next component and repeat above procedure for bellow component.
After completing above steps the geometry looks like this

To create 1D element property cards first create two properties for upper and lower bracket models.
And also create one material card.
Property card consists of Pshell as property and enter the thickness value 2.5 and 2 resp.
In material card insert E,RHO,Nu values of steel material by default.

Case I)

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

First to creaate ROD,BEAM,BAR elements create a cross section respectively.
Go to 1D-Hyperbeam-Standard section and add respective values given as above-create.
Now for creating RBE2 link go to 1D-Rigids-Select indepenedent node as calculated and select dependent nodes as element nodes of washer.
After creating RBE2 go to rod and select respective nodes from upper and lower bracket and create.
Assign Rod property to created element and also DOF's.

Case II)

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

To create 1D beam element go to 1D-Hyperbeam-Standard section and add respective values given as above-create.
Now for creating RBE3 link go to 1D-Rigids-Select indepenedent node as calculated and select dependent nodes as element nodes of washer.
After creating RBE3 go to rod and select respective nodes from upper and lower bracket and create.
Assign Beam property and material to created element and DOF's.
After completion of above steps the model look like this.

Case III)

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

To create 1D bar element go to 1D-Hyperbeam-Standard section and add respective values given as above-create.
Now for creating RBE3 link go to 1D-Rigids-Select indepenedent node as calculated and select dependent nodes as element nodes of washer.
After creating RBE3 go to rod and select respective nodes from upper and lower bracket and create.
Assign bar property and material to created element and DOF's.
After completion of above steps the model look like this.

Case IV)

Apply mass at D amd E locations.

Case V)

Join the two components with Spring elements.

To create spring element at prescribed location go to 1D-spring-Select property spring-element type CELAS1-create.

Conclusion:

I)Creation of 1D elements such as BAR,ROD and BEAM are important in full body analysis of any assembly component of automobile.

II)Connectvity and Rigid body creations are very important aspects.

III) 2D meshing also important for getting accurate results.

Gdrive link:https://drive.google.com/open?id=1JTcYBDcqFUPn_EUSZvHnwhr9KLUD8CwC

Ship work like this
in your own course.