Homework, Quizzes, Simulation Examples — Damping Effects — Lesson 4

Simulation Examples

Several simulation examples are provided here. Each of them comes with a description file, video instruction, and Ansys simulation file. All of the simulations are conducted using Ansys simulation software. Download the student version of Ansys software here.

(1) Cabinet Enclosure Vibration

Installed electronic devices/components experience vibration loads. This vibration may cause damage to the components or the connections (solder) between them. An analysis of an assembly subjected to vibration will provide better insight into the deformation pattern and frequency response of the system. Without damping, the peak displacement of a requested vertex at resonance boosts up to 105 mm. Add a damping coefficient of 0.025 and check the frequency response result on the same vertex. Download the zip file and extract the contents. Go through the Readme file. Follow along with the provided How To Video file.

(2) High-Frequency Damper Using Viscoelastic Materials

This example shows a simulation of the harmonic response analysis of a viscoelastic damper. The effect of viscoelasticity is emphasized by comparing two models with and without a viscoelastic material. The maximum deformation with the damper decreases by an order of magnitude at the testing frequency range. Download the zip file and extract the contents. Go through the Readme file. Follow along with the provided How To Video file.

(3) Acoustic Analysis of a Small Speaker

Designing a speaker involves conducting a structure–acoustic analysis: the structure (speaker) generates acoustic waves and releases energy into the air, and the air impedance influences the structural behavior in turn. This analysis can improve the design in terms of material selection, component thickness and other parameters to obtain optimal performance in the operating frequency ranges (bass, midrange, and treble). When selecting materials for a speaker, an important parameter is damping. Explore the simulation with the instruction files and discover how the sound pressure level changes with frequency. You are encouraged to alter the material damping values and see how the sound pressure changes. Download the zip file and extract the contents. Go through the Readme file. Follow along with the provided How To Video file.

Homework

(1) Automotive Suspension System with Shock Absorber

A shock absorber in a car's suspension system can help the car dampen the vibrations caused by, for instance, a bump on the road. In this simulation, the process of simulating in Ansys Mechanical the response of a simple car suspension system to a bump is described. Viscous damping from the shock absorber will be the focus of this simulation. Follow the instructions to replicate the simulation and obtain the response with and without a damper. Answer the questions below.

(a) At the damping value of 0.5 lbf.s/in, what is the damping ratio of the whole suspension system? (Hint: compare the maximum deformation magnitude at different vibration cycles.)

(b) Apart from the damper, what other types of damping can be added to a shock absorber? Add your design to the simulation and test the new shock absorption effect. (Hint: think about a flat tire and an inflated one.)

Download the zip file and extract the contents. Go through the Readme file. Follow along with the provided How To Video file.

 

(2) GoPro Harmonic Analysis

This simulation presents a simulation of harmonic analysis on a GoPro camera. It is likely for a GoPro camera to undergo low-frequency vibrations under service load, so it is essential to detect and avoid resonance-caused potential damage to the components.  Follow the instructions to replicate the simulation and answer the questions below.

(a) Does the damping in these two joints help if the GoPro falls from a height to the ground? What design criteria is needed in this case?

(b) Assuming the GoPro is used by a skier who skis on a bumpy slope, estimate the load frequency range. Does it agree with the frequency range requested in the simulation?

Download the zip file and extract the contents. Go through the Readme file. Follow along with the provided How To Video file.