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Full Vehicle NVH
Access the Assemble, Analyze, NVH Tools, NVH Post, and Physics AI ribbons.
Post-Processing and Diagnostics
Define radiation conditions and create emissivity models.
Multiple Sample Analysis
Post-process results from a Multiple Sample Analysis, including plotting a spread of responses (+/-95% and mean).
Multiple Sample Analysis, Loads MSA - Display
Plot responses for runs with highest and lowest responses for a particular frequency or a range of frequency.

Welcome
What's New
View new features for HyperMesh NVH 2024.1.
Get Started
Learn the basics and discover the workspace.
Tutorials
Discover NVH functionality with interactive tutorials.
Full Vehicle NVH
Access the Assemble, Analyze, NVH Tools, NVH Post, and Physics AI ribbons.
- Assembly
  Learn how to create, open, import and save models.
- Analysis
  Set up the simulation model, materials, domains and boundaries.
- NVH Tools
- Prepare Module
  Create, organize and manage the CAE parts.
- Post-Processing and Diagnostics
  Define radiation conditions and create emissivity models.
  - Load an NVH Utility
  - Integrated Diagnostics
    Calculate a response, perform contribution analysis, plot results, and perform diagnostic studies and study response changes.
  - Modal Participation
    Plot modal/panel participation curves from an OptiStruct .h3d file or an MSC Nastran .f06/.pch file.
  - Grid Participation
    The Grid Participation utility allows you to plot panel grid participation results and then use advanced scaling contour capabilities to isolate key contributing areas.
  - Energy Distribution
    Visualize the distribution of energy within a full vehicle NVH model, as a way to understand what components are dominating the vehicle response.
  - Transfer Path Analysis
    Identifies the complex contribution of the excited structure through attachment points to a response in the responding structure.
  - Design Sensitivity Analysis
    Design sensitivity represents a change in response with respect to a change in a design variable, which is typically used for optimization.
  - Order Analysis
    Generates and post-processes engine order related data from an OptiStruct or Nastran frequency response analysis that contains either RPM-based loading subcases or order-based loading subcases.
  - Modal FRF
    Calculate a frequency response based on modal results.
  - Model Correlation
    The Model Correlation utility determines the degree of similarity or correlation between two sets of results.
  - Radiated Sound
    The Equivalent Radiated Sound utility post-processes the results of exterior structure-borne radiated sound.
  - Global Modes
    Identifies global modes from an OptiStruct or Nastran modal analysis.
  - Flow Induced Noise/General Signal Processing
    The General Signal Processing utility processes the time domain pressure results from CFD simulations and visualizes the results in both the time and frequency domain.
  - Green House Noise
    Post-process the pressure result of a vehicle panel obtained from ultraFluidX.
  - Mount Optimization
    Predicts powertrain rigid body mode frequencies and kinetic energy distribution, which play a critical role in optimizing the mount stiffness and layout configuration, by decoupling powertrain rigid body modes and reducing vibration transmission.
  - Optimization, RBDO
    Optimizes sensitive parameters for multiple sample analysis results using the RBDO or Deterministic approach.
  - Multiple Sample Analysis
    Post-process results from a Multiple Sample Analysis, including plotting a spread of responses (+/-95% and mean).
    - Multiple Sample Analysis, Structures MSA - Load
      Load a .tpl template file from a Structures MSA analysis.
    - Multiple Sample Analysis, Structures MSA - Display
    - Multiple Sample Analysis, Loads MSA - Load
      OptiStruct/Nastran *.pch file that has transfer function results for wheel sensitivity or driveline sensitivity.
    - Multiple Sample Analysis, Loads MSA - Display
      Plot responses for runs with highest and lowest responses for a particular frequency or a range of frequency.
  - Deterministic Optimization
    Reads results from an OptiStruct optimization run and processes the results to review the overlay of the NVH responses, baseline versus optimized. Compare changes in the design variable values, baseline versus optimized.
  - Display Options
    Customize plots using the following options
  - Filter Contributors
    Filters contributors to a smaller set of data.
High Frequency NVH
High frequency NVH is an implementation of Statistical Energy Analysis (SEA), and is used to predict and analyze the vibration and acoustic response of complex dynamic systems.
Squeak and Rattle
Create and evaluate evaluation lines and optimize interfaces to eliminate squeak and rattle issues.

View All Altair HyperWorks Help

Multiple Sample Analysis, Loads MSA - Display

Plot responses for runs with highest and lowest responses for a particular frequency or a range of frequency.

Figure 1. NVH-Utilities Browser - Display tab (Loads MSA)

It is also possible to review the randomized values used for the variables in a particular run. From the Parameter Effects tab, plot sensitive parameters contributing to response scatter at a particular frequency. Before using this tab, you must first load a file from in the Load tab.

Run Info

Allows you to visualize responses for highest and lowest responses. Also allows review of parameter values used in specific run.

Speed Selection: Select an option to choose specific speed or speed range.
Specific Speed: Enter a specific speed or use the slide bar to select a frequency value.
Speed Range: Speed range indicates the available range, based on your result PCH file. Using the From and To fields, you can customize your own frequency band.
Show Highest, Lowest and Nominal: See the runs with highest, lowest and nominal runs.
Show highest runs: Select the number for which the you want to see the runs with highest responses.
Show lowest runs: Select the number for which the you want to see the runs with lowest responses.
Display Options: The Display Options dialog allows you to customize the plot, including scale, weighting, and the plot layout.
Display: Click Display to display the response plots, for chosen number of highest/lowest runs.
Run Directory: Select the directory with Multiple Sample Analysis runs.
Run Number: Click the response curve and the corresponding run number is listed. It is also possible to enter the run number manually.
Contributors: Review of randomized parameter value used in selected HyperStudy run.

Figure 2. Response for highest, lowest, and nominal runs with respect to vehicle speed (bottom X-axis) and frequency corresponding to imbalance planes (top X-axis)