The Finite Element Method - Java applet

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Screenshot of the applet

Here we have made an applet were you can try out simple Finite Element analysis yourself. To start the applet, click link below, or use the "subthemes" button


Fem2D Java applet

(1024 x 768 screen resolution or more recommended)

Features:

GUIDELINES

Preprocessing:

The applet lets you choose several different models that you can play around with. The models are:

  • Model 1 - A flat plate
  • Model 2 - A flat plate with one rounded edge
  • Model 3 - A beam
  • Model 4 - A flat plate with semicircular cut-out
  • Model 5 - A cylinder liner (Exercise 3 in the course SIN 2046)
  • Model 6 - A simple frame corner (Exercise 10 in the course SIN 1040)
The following models can be used for stress concentration studies:
  • Model 7 - A flat plate with circular cut-out (a/b = 1)
  • Model 8 - A flat plate with elliptical cut-out (a/b = 2)
  • Model 9 - A flat plate with elliptical cut-out (a/b = 5)
If you want to change loads or boundary conditions, simply select a side or a node, and then use the left pane to edit it. Remember to push "Update side/node" when you are done.

You can choose what type of elements yo want to use in the analysis. Select between three-noded constant strain triangle or four-noded quadrilateral elements. You can then choose the number of elements, that is, the coarseness of the mesh, and you can change material and thickness. You are now ready to generate the mesh.

Mesh generation

After the mesh is generated, it will be displayed on the screen. The program will also do a quick validation of loads and boundary conditions. If there are any problems, a message will appear, and you should go back and change loads or bondary conditions. This validation fails when there are no loads, or it will react on boundary conditions if there are too few of them so they permit some kind of movement of the entire geometry, either translation or rotation.

If you want, click on an element to bring up data about it. You can now see wich internal number the element has, which nodes it consists of, and many metarial properties of the element. You are not, however, able to change anything.

You are now ready for analysis.

Analysis

The analysis consists of a lot of internal calulation, and may take a while if you have a lot of elements and a slow computer. The program will report the time of the analysis for comparison studies. After the calculations are done, you are ready for postprocessing.

Postprocessing

You will now see a contour plot of the stresses in the analysed model. Von Mises stresses are shown by default. You can now change the stresses you want to plot (x-stress, y-stress, shear stress or Von Mises-stress), or you can choose to plot displacements

You can display the original model and/or the mesh with the plot, and you can view the mesh and plot as deformed. Here you may want to increase the exaggeration factor of the deformed plot as deformations may be small.

In addition, you can select an element, and get stress data for that particular element. You will now see on the left side stress data for the centroid (x-stress, y-stress, Von Mises-stress and shear stress), and you will see the maximum and minimum nodal Von Mises-stress for the element.

When you are done, you can go back and change geometry, loads, boundary consitions or mesh properties. Good luck!