2C. Path Operations To Compare Stress at different positions

We have to define path but instead of using locations of points to define path, we can use a set of nodes.

In this section, you will plot

1. Von Mises Stress at node 195, 201 and 207

2. Von Mises Stress at node 2020, 2030 and 2030

Here we will concentrate on the first plot.

GENERAL POSTPROC -> Path Operations

Then, you will see the following window. Type the number of nodes in the order you want them to appear on the plot. The first node is 195. Then press Enter using your keyboard. You will notice that the "Count" variable has been incremented. Then type the second node which is 201. Press Enter key on your keyboard. Type the last node which is 207. Then click OK.

                                    

Then you will see the following window. Type in the name of the path. In the "Number of divisions" box, enter 0. Enter 3 for the box, "Number of data sets".

What we have to do next is to specify which values of stresses we want to plot.

PATH OPERATIONS -> Map onto Path

We have now selected the Von Mises Stress. Now, we will want to just plot the graph.

PATH OPERATIONS -> Plot Path Items

PLOT PATH ITEMS -> On Graph

Highlight SEQV which represents Von Mises Stress.

You will then get the following graph. The plot provided by ANSYS is actually misleading. Along the path you have chosen you would not expect the Von Mises stress to vary by much. The plot shows a variation of approximately ± 5%, but that variation appears large due to the auto-scaling of Y-axis values by ANSYS. Oscillations in stress values for distance values between 0 and 1.5 are not physical. They are caused by our somewhat coarse mesh.

Below you will see a plot of the Von Mises stress along the path defined by nodes 2020, 2030 and 2040. The plot yields the expected result that the Von Mises stress along this path decreases (roughly by a factor of z) as one moves from the crankshaft (left) end to the pedal (right) end.