# Simulation Quiz 2

### Electronics Enclosure Damping

Electronics are often housed in an enclosure as part of a system (computer, control system, etc.) This enclosure offers protection and may be mounted directly to a mechanical system such as a car, ship, aircraft, etc. These electronics may be subjected to harsh vibration environments. Consider a control unit in your car. When you drive over rough roads, the electronics are subjected to such a vibration environment. Understanding how the electronic PCB boards will vibrate, deform, and be stressed is of concern to those designing and certifying the electronics. In this problem, we will subject an electronics enclosure with an enclose PCB assembly to a harmonic based excitation, simulating periodic, cyclic excitation that may result in dynamic amplification of the PCB, and the associational unwanted deformations, stresses and strains. One key parameter to quantifying the magnitude of the deformations, stresses and strains is the damping that is specified for the system. In these simulation exercises, you will be setting up the simulation and extracting key results quantities.

Follow instructions to set up the simulation and get results BEFORE starting the quiz. Download the instructions and necessary simulation files from here.

Note: The Expected Completion Time for this quiz is 20 mins but, the Maximum Available Time to complete the quiz is 45 mins.

#### Total Number of Questions - 15

Times up!

Capturing Complex Response of Structures - Simulation Quiz 2

Complete the simulation and have all the results ready BEFORE starting the quiz.

Once you have finished the exam, click on the 'Mark Complete' button to save your progress and move to the next section.

1 / 15

In System B (“Harmonic Response”), right-click on the Frequency Response output corresponding to deformation in the x-direction, then select “Create Contour Result.” Select the best option that describes the contour result

2 / 15

In System A (“Modal”), for the first natural frequency, the max total deformation (eigenvector) occurs on component named _____.

3 / 15

In System A (“Modal”), the first natural frequency is _____.

4 / 15

In System A (“Modal”), review the Participation Factors in the z-direction. Now, in System B (“Harmonic Response”), review the Frequency Response of deformation in the z-directions. Select the option below that is a correct statement.

5 / 15

In System A (“Modal”), review the frequency and participation factor of Mode 7. Now, in System B (“Harmonic Response”), review the Frequency Response of deformation in the x-direction near the same frequency as Mode 7. Select the best option below that is correct.

6 / 15

In System B (“Harmonic Response”), review the Frequency Response of deformations in the x-, y-, and z-directions. Select the best option below that is correct.

7 / 15

In System B (“Harmonic Response”), considering all surfaces, the maximum amplitude of deformation from the frequency response plot in the y-direction is _____.

8 / 15

In System B (“Harmonic Response”), considering all surfaces, the frequency of the maximum amplitude of deformation in the x-direction occurs _____.

9 / 15

In System B (“Harmonic Response”), review the Frequency Response output in the x-direction. If the damping ratio was increased from 5% to 10%, what will happen? Without solving such a simulation, select the best option that correctly describes what will occur in such a case.

10 / 15

In System B (“Harmonic Response”), considering all surfaces, the maximum amplitude of deformation from the frequency response plot in the x-direction is _____.

11 / 15

In System B (“Harmonic Response”), review the Frequency Response of deformation in the x-direction. If the damping ratio was decreased from 5% to 0%, what will happen? Without solving such a simulation, select the best option that correctly describes what will occur in such a case.

12 / 15

In System A (“Modal”), which mode has the highest Participation Factor in the x-direction?

13 / 15

In System B (“Harmonic Response”), review the Frequency Response of deformations in the x-, y-, and z-directions within the frequency range of 250 to 500 Hz. From the output of maximum deformation, select the best option below that is correct.

14 / 15

In System B (“Harmonic Response”), review the Frequency Response output in the x-direction. If the damping ratio was decreased from 5% to 2%, what will happen? Without solving such a simulation, select the best option that correctly describes what will occur in such a case.

15 / 15

In System B (“Harmonic Response”), considering all surfaces, the frequency of the maximum amplitude of deformation in the y-direction occurs _____.