LMS International has announced the release of its new Transient Acoustic Holography module within the LMS CADA-X Noise & Vibration testing software suite. Acoustic holography is an industrially proven technique that uses the measurements taken in one plane to predict what the readings would be in any other plane. As such it is ideal for source location, especially in multi-source environments, like in full vehicle NVH troubleshooting.
Until now acoustic holography has mainly been applied to stationary conditions. In order to analyze transient or pseudo-stationary conditions, LMS introduced Transient Acoustic Holography. This new tool enables the user to look at pressure changes at particular frequencies/orders as a function of time/rpm. It is therefore the ideal tool to localize, quantify and rank sound sources on transient sound signals such as engine run-ups.
The new LMS CADA-X module has been implemented in such a way that it does not require all data to be measured simultaneously -saving large amounts of money on microphones and high channel count systems.
Some of the key features of the new Transient Acoustic Holography:
Until now acoustic holography has mainly been applied to stationary conditions. In order to analyze transient or pseudo-stationary conditions, LMS introduced Transient Acoustic Holography. This new tool enables the user to look at pressure changes at particular frequencies/orders as a function of time/rpm. It is therefore the ideal tool to localize, quantify and rank sound sources on transient sound signals such as engine run-ups.
The new LMS CADA-X module has been implemented in such a way that it does not require all data to be measured simultaneously -saving large amounts of money on microphones and high channel count systems.
Some of the key features of the new Transient Acoustic Holography:
- The following analysis selections as function of rpm are available: a frequency range, a single order, a sum of single orders or a range of orders. These selections permit respectively the study of resonance, order, and modulation phenomena, as well as component studies
- Back - and forward propagation to predict acoustic fields anywhere from the source to the far field in a plane parallel to the hologram (measured) plane
- Pass-by noise predictions: you can predict pressure, intensity and velocity along an axis of a simulated moving source
- Simulation of source attenuation: you can define multiple sources and attenuate/amplify them individually or simultaneously for parallel or pass-by noise predictions.
With the upcoming Revision 3.5.C of LMS CADA-X, a time domain module will extend the acoustic holography family, which will be particularly suited to the study of very short transient phenomena (for example, less than a second). Typical applications in automotive development include the analysis and troubleshooting of a car door slam, gearshifts and starter motor noise.
LMS CADA-X Acoustic Holography is being used at major companies across different vehicle industries. Reference customers include Daewoo, Elasis, Ford, GM, Jaguar, Jatco, Pininfarina, PSA, Reiter, Renault, and Volkswagen.
About LMS International
LMS is an engineering innovation partner for companies in the automotive, aerospace and other advanced manufacturing industries. LMS enables its customers to get better products faster to market, and to turn superior process efficiency to their strategic competitive advantage. LMS delivers a unique combination of virtual simulation software, testing systems, and engineering services. We are focused on the mission critical performance attributes in key manufacturing industries, including structural integrity, handling, safety, reliability, comfort and sound quality. Through our technology, people and over 25 years of experience, LMS has become the partner of choice for most of the leading discrete manufacturing companies worldwide. LMS, a Dassault Systèmes Gold Partner, is certified to ISO9001:2000 quality standards and operates through a network of subsidiaries and representatives in key locations around the world.
LMS CADA-X Acoustic Holography is being used at major companies across different vehicle industries. Reference customers include Daewoo, Elasis, Ford, GM, Jaguar, Jatco, Pininfarina, PSA, Reiter, Renault, and Volkswagen.
About LMS International
LMS is an engineering innovation partner for companies in the automotive, aerospace and other advanced manufacturing industries. LMS enables its customers to get better products faster to market, and to turn superior process efficiency to their strategic competitive advantage. LMS delivers a unique combination of virtual simulation software, testing systems, and engineering services. We are focused on the mission critical performance attributes in key manufacturing industries, including structural integrity, handling, safety, reliability, comfort and sound quality. Through our technology, people and over 25 years of experience, LMS has become the partner of choice for most of the leading discrete manufacturing companies worldwide. LMS, a Dassault Systèmes Gold Partner, is certified to ISO9001:2000 quality standards and operates through a network of subsidiaries and representatives in key locations around the world.


