Risk Analysis and Basic Screening

Use SnRD to identify Squeak and Rattle issues.

Risk Analysis & Basic Screening use case describes the basic screening analysis that the S&R analyst would perform. Starting from a NVH FE-model, built for other purposes, the analyst wants to define a first set of E-lines to assess the S&R performance of a system. Typically, this first analysis will occur at the early stage of the virtual development process, thus a lack of input might be a road blocker for the S&R CAE engineer. Therefore, the SnRD simple process will close this gap by offering automation and a set of default settings enabling this first analysis.

Typical information lacking at this stage of the development are:
  • Interface to be analyzed
  • Dimensions and properties
  • Loading Conditions
Objective
  • Create FE model prepared for analyzing Squeak and Rattle
    • Create Rattle E-Lines using Auto method.
  • A SineSweep loadcase, with user settings.
  • Run analysis, create summary page and export PPT report.
Starting Point
  • Clean FE model- no SnRD information.
Below is an illustration of the workflow-
Figure 1.
In this usecase, you will perform the following steps-
  1. Import tutorial model
  2. Define Interfaces.
  3. Create Evaluation Lines at interfaces.
  4. Create SineSweep based Dynamic event and export solver deck.
    • Solve the .FEM solver deck to obtain results and files.
  5. Use the solver deck, E-Lines definition file and to post process results.
    • Generate histograms, contour plots, etc.
  6. Generate PPT report HyperWorks Report tool.

Files Required

Files required to complete the usecase.

Use the files in the <HyperWorks Installation Directory>\hwdesktop\demos\snr\001_Model folder

Step 1: Import Model

Using the Import task, you will import the required set of files.

Below are the steps to import files model, DTS and material files:

  1. Using the file browser option in the Model Import field, browse and select tutorial_ip_snr_model.hm file.
  2. Click Import.
    This will import the selected model to the session.
    Figure 2.

Step 2: Define the Interface Between Components by Creating Geometric Lines

Create geometric lines which will be used to define the interfaces to evaluate.

Create Geometric Lines

Use Create Geometric Lines tool to create geom lines in the model.

  1. In the HyperWorks toolbar, from View option, select QuickReviewComps.
    Figure 3.
    This isolates only the components which are needed for squeak and rattle assessment.
  2. From Setup group, select Define Interface.
    Figure 4.
    A guide bar will appear.
  3. Click to open advanced options.
    Figure 5.
  4. Enable Min check box and enter 800 as the input value,
  5. Select the complete model from graphics area.
  6. Click .
    This will create the geometric lines at the component edges in the model.

Step 3: Create E-Lines

Create and Manage all the E-Lines in the model.

Create E-Lines

Use Create E-Lines tool to create E-Lines at the interfaces.
  1. From Setup group, select Create E-Line tool.
    Figure 6.
    A guide bar will appear.
  2. Select all the components for Components option.
  3. Select all the lines for Lines option.
  4. Click .
    This creates 11 E-Lines in the model.
    Figure 7.

Realize All E-Lines

Using the Manage E-Lines tool, realize all the E-Lines in the model.
  1. From Setup group, select Manage E-Line.
    Figure 8.
    A guide bar will appear.
  2. Select to Realize All or only the E-lines of a specific type.
  3. Click .
    A user message will appear. Click Yes.
    Figure 9.
    This realizes all the E-Lines in the model.
    Figure 10.

Manage E-Lines

From the Realize All E-Lines process you see that there are duplicate interfaces created. Using the Manage E-Lines tool, review and delete duplicate E-Lines.
  1. From Setup group, select Manage E-Lines > Review E-Lines.
    Figure 11.
    Review E-Lines table will appear.
    Figure 12.
  2. Optional: Scan through E-lines and delete possible duplicates.
    1. Click .
      A user message appears. Click Yes to delete selected lines.
      Figure 13.
You can revert to original view with all components visible.

Step 4: SineSweep Loadcase Setup and Export OptiStruct File

Setup a SineSweep Loadcase and export the solver file. Solve the file using OptiStruct to obtain output files.

SineSweep Loadcase Setup

  1. From Setup group, select Dynamic Event.
    Figure 14.
    A guide bar will appear.
  2. Click to view advanced options. Define 4 as the input value for Output Frequency under Time Step option. Accept other default values.
    Figure 15.
  3. From the graphics area, select the node shown in the below image.
    Figure 16.
    A microdialog will appear.
    Figure 17.
  4. Select D- displacement.
  5. Select SineSweep for Load Curve.
  6. Select Z for load direction.
  7. Click .
    This creates the SineSweep loadcase with the load collectors and other entities required for the simulation. You can view the model browser for the new entities that are created.
  8. Curve Editor window appears.
    Review the SineSweep load curve and close the window once done.

Export OptiStruct Solver File

  1. From Analyze group, select Export OptiStruct Solver File.
    Figure 18.
  2. Model Export window will appear.
    Figure 19.
  3. Click Export.
    A folder selection window will appear.
  4. Browse and select the required folder.
    This will export the OptiStruct solver deck file to the selected folder. Click Close to close the model export option.
Use the exported .FEM solver deck to solve on OptiStruct solver. Once done, two output files are generated: .H3D and .PCH. These files will be used in the Post Processing of results.

Step 5: Risk Assessment

Evaluate risks for Squeak and Rattle with the Risk Assessment tool.

  1. Open Risk Assessment tool.
    Figure 20.
  2. Select model file (.fem) if not already selected.
  3. Select .pch file generated after solving the model file.
    Sinesweep loadcase is selected in Load Step list.
  4. In Rattle Tab, Select Relative Displacement MAG.
  5. Click Plot.
    Relative Displacement plot for the E-Lines are plotted in the HyperView window.
    Figure 21.
  6. Optional: Plot the remaining of the results to perform detailed study.

Step 6: Generate Summary Report

Export a Squeak and Rattle summary report using HyperWorks Report tool.

Learn more about HyperWorks Report tool.
  1. In the active HyperWorks session, click Report.
    This launches the Report ribbon..
    Figure 22.
  2. Click Capture .
    Figure 23.
    Select Capture Session from the Add Module window. This launches the Report tab and the report module is added in the tree.
  3. Click Export.
    Figure 24.
    This will execute the module and generate outputs. A file browser window will appear.
  4. Enter SnR Risk Summary Report in the File Name and click Save.
    This generates the document report and will launch automatically.
    Figure 25.