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FEA Series Part 2: Data Alter Using IF Conditions


In Part 1 of this series, we were looking at a connecting rod data set.

Von Mises Stress was calculated from the stress vectors, and then we showed areas of high stress using the contour color cutoff parameter. In this video we will be analyzing the same data set to find a stress threshold using an IF condition.

We will start this process with the Von Mises stress already calculated and value blanking toggled on to hide the crankshaft and cylinder.

To calculate the stress threshold we will be using the Specify Equations dialog and enter the following:

{maxStress} = IF ({Von Mises Stress}>402, 1, 0)

MaxStress is the variable we are calculating. The IF keyword follows the same functionality as Excel’s IF function where the first parameter is the test condition. In this case, we are looking for the regions where Von Mises Stress is higher than 402. The MaxStress variable will be set to the next two parameters if the point satisfies or fails the test condition, respectively.

Once calculated, the contours are toggled on to show the newly calculated variable. This is done by going into Contour Details and changing the variable being defined.

At this point, we can start to see the regions where the stress threshold is being crossed. However we are expecting to see only values of 0 or 1. Any colors not blue or red are places where Tecplot 360 is interpolating between the two values. We would like to skip this interpolation and go into the Zone Style dialog and set the contour type to primary value flood.

The resulting plot shows the regions where the Von Mises stress tolerance is being met or exceeded.

Thanks for watching!