NVH, Frequency Domain, Fatigue

The objective of the training course is to introduce the frequency domain vibration, fatigue and acoustic features of LS-DYNA to users, and give a detailed look at the application of these features in vehicle NVH simulation.

This course is recommended for engineers who want to run NVH or other frequency domain vibra­tion, fatigue and acoustic simulation problems with LS-DYNA. This course is useful for engineers and researchers who are working in the area of vehicle NVH, aircraft/spacecraft vibro-acoustics, engine noise simulation, machine vibration testing and simulation, etc.

Contents

• Introduction
  NVH theory and lab testing technology, overview of LS-DYNA frequency domain features and applications, frequency domain vs. time domain, Fourier transforms
• Frequency Response Function (FRF)
  Modal superposition method, damping, nodal force/resultant force FRF
• Steady State Dynamics (SSD) with harmonic loading
  Large mass method for enforced motion, Equi­valent Radiated Power (ERP), mode expansion with LS-PrePost
• Random vibration with PSD loading
  Correlated and uncorrelated multiple PSD excitations, acoustic wave, pre-stress condition
• Acoustics
  Rayleigh method, Kirchhoff method, BEM, FEM, acoustic panel contribution analysis, vibro-acoustic problems, Muffler transmission loss analysis, ATV and MATV techniques, acoustic eigenvalue analysis, incident waves, half-space problem, weighted SPL, radiated sound power
• Response spectrum analysis
  Input earthquake spectrum, modal combination methods (SRSS, CQC, etc.), multi input spectra
• Fatigue
  Fatigue analysis in harmonic/random vibration environment, Miner’s rule, S-N curves, Dirlik method
• Advanced topics
  SEA (Statistical Energy Analysis), brake squeal analysis; NVH based on IGA
• Workshop