Dr. Zhang

Team 2

Bryan Hays

ENME 414

Crushing can case study

Aluminum soda cans are ubiquitous in society. There is a lot of engineering that goes into these cans. They are required to contain a beverage under pressure, while at the same time, it must be easily opened and easily compacted for recycling. We have all crushed and empty can with our hands. Have you ever wondered what happens in the Aluminum? Using ALGOR, we can see what kind of stresses and strains are present in the material of the can when a crushing force is applied to the sides and top of a model can. ALGOR is also capable of showing us the final deformed shape of the can.

In this case study, we will use ALGOR’s Superdraw modeler to create the can model, then, once ALGOR runs its analysis, we can view the results using ALGOR’s Superview tool.

Using the Superdraw III Interface.

The can model is created by revolving an outline of the can about the z-axis. We then assign to this shell we create a thickness and the physical properties of aluminum.

• Start ALGOR with Roadmaps
• Choose the yz plane view from the View Utilities palate
• Click the line button from the add CAD objects menu
• Specify the points to determine the line by typing them into the X, Y, Z boxes at the bottom right of the Superdraw window
• Enter the coordinates (0,0,.2), (0,1.75,0), (0,2,.25), (0,2,5), (0,1.75,5.25), (0,1.7, 5.2), (0,0,5.2) and click "done"
• Choose "select:point" then click on the long side
• From the menu choose "construct:divide:number" enter 10
• Click"divide:done" do this for the angled parts at each end of the long side, but enter 3 instead of 10
• Select in the menus "select: all" then "modify: copy" Click the box next to "join all copies" so that join all copies is selected
• Click"number" and enter 20 for the number of repetitions then "done"
• Click "quick RMS:angle" and enter the angle as 18 then click "done"
• Click "rotate last"

… And voila, there is your can!

Now we can put boundary conditions on the model.

• From Menu choose "FEA add: stress and dynamic analysis: boundary conditions"
• Click "change values" and uncheck Rx, Ry, and Rz then click "done"
• Choose color 3 as the active color by clicking where it says"C=1" at the bottom of the window and then clicking "3"
• Click "box apply" and then draw a box around only the lowest set of nodes on the model

  Do the same thing for the topmost set of nodes but re-check Rx, Ry, and Rz and uncheck Tx, Ty, and Tz

The boundary conditions will show up on the model. Now you can add some forces.

• Make color 1 active
• From the menu select " FEA add: stress and dynamic analysis: nodal forces: vector: Z: negate: done"
• Then select "magnitude" enter 1 "done"
• Select "load case" enter 1 "done"
• Select "box apply" and select the top 2 layers of nodes when seen from the front
• Click "vector: Y: done: box apply" and select 6 visible nodes on the left side in the center of the left side
• Click "vector: Y: negate: done: box apply" and select 6 visible nodes on the right side in the center of the right side
• Save and Save often

There are your forces. Now we move on to specifying material properties.

• Click "element data" at the bottom of the window
• Choose "linear stress and dynamics"
• Click the box under "element" choose "plate," type <can> in the tag area "ok"
• Click under "data"

  This will bring you to a no-mouse area, use the arrow keys to navigate

• Start with "elements: type: plate" <esc>
• Then "elements: info: vebuke"
• Then "elements: group" and <tab> over to "lib" hit <enter> and choose aluminum
• Next "elements: color" and enter .02 for thickness of color 0
• Move over to "global: load case" type 20<enter>10<enter><esc>
• Go to "decode: run"
• Click "create" when you dump back into Superdraw III
• "file: exit"

Now it is time for some analysis.

• Start by clicking "Run Time Options" then check the top box as well as the 5^th one from the top
• Click "up" and select "analyze"
• When it is finished, select" view analysis results"

Using Superview to check the Analysis

Follow these directions from the ALGOR tutorial that help to show you some of the different stresses and strains calculated by ALGOR

• "Stress-di: Hidden l" <Esc> gives a different view
• "Light: material" another way to look at things
• <F9>"Stress-di:Eq+other" look at equivalent stresses
• <F9>"Files:Sav param" save the results you are checking on
• "Displaced: Calc scal: Displ on" how it looks after the forces are applied
• Stress-di:Post: strAin di: maX prin" max principal strain
• "von Mises" von Misses stress
• <F9>"strEss di: Precision" precision contour

This is neat and useful stuff.

With some knowledge and some clicking you can easily model other parts.

A little about ALGOR.

ALGOR is not the most intuitive software to learn. It takes quite a bit of practice before one begins to understand how to make things work. Once you do get the hang of ALGOR, you will notice some of its strengths and weaknesses. The modeler in ALGOR is very weak in comparison to pro/engineer and other modeling packages. A nice way to deal with more complex models is to create them in Pro/Engineer and import them into ALGOR as an IGES file. The meshing of the 3-d model can be done in Pro/FEM or ALGOR.

For simple models like the one we created here, the ALGOR modeler is sufficient. One of its strong points is the ability to assign different parts, forces, and conditions as different groups, colors, and layers. It is important to assign things different colors so that they can be easily removed should you make a mistake. Deleting or choosing particular parts and conditions is another area where ALGOR’s Superdraw III is lacking, so be sure to keep everything neat. Meshing can be done using the Houdini program and results visualization is done in Superview.