Figure 1: Meshed mudguard.

Response Dynamics is a crucial analysis before the product construction. A mechanical engineer must be aware of the dynamic phenomena that occur in the structure. The combination of static and dynamic simulation will assure us that it will remain within safe limits during its operation.

This blog article is a presentation on how to perform a Random Event simulation by using Simcenter 3D Response Dynamics (SOL103). Random base excitation is prevalent in the space, automotive, and electronics industries. The purpose is to simulate the random response of a mudguard.

The activated response dynamics solver has already a Simcenter Nastran sol103 solution which will be used to calculate the structure’s Modes. You can change the amount of the Modes by pressing right-click on the Subcase- Dynamics.

Figure 2: Steps to change the number of modes.

 The next step is to activate the Response Dynamics wizard and press the button:

In the tree that creates in the Simulation Navigator, you can visualize and modify the mode’s characteristics.

For the characterization of the dynamic phenomenon, you must create an Event to select the type of Excitation that you want to simulate.

It is time to discuss the response of the structure in Figure 1. The excitation (.afu file) that the structure receives is the following and specified in the Event section:

Figure 3: Used excitation for the response dynamics.

This excitation is loaded through the holes, in the direction of the y-axis.

Post-process is the last step of the analysis. You can select nodes to see the displacement or velocity or acceleration in the frequency spectrum.

Figure 4: Two points of interest.

Figure 5: Displacement/Frequency plot.

Figure 6: Acceleration/Frequency plot.

The frequency spectrum from 5Hz to 100Hz, these points are not close to the eigenvalues of the structure and the displacements are not maximized. So, the structure works within safe limits.

Figure 7:Peak results for acceleration.

With these steps, anyone can simulate the response on a dynamic load.

We at FEAC hope that this blog post has been interesting and that you will be able to create a nice FE Analysis after reading this. If you have any questions, you are always welcome to contact us at support@feacomp.com