MID-MOD

Mid-frequency vibro-acoustic modelling tools / Innovative CAE methodologies to strengthen European competitiveness

 Partecipanti

Mappa

 Word cloud

Esplora la "nuvola delle parole (Word Cloud) per avere un'idea di massima del progetto.

 Obiettivo del progetto (Objective)

'Noise and vibration have a very large impact on the competitiveness of transportation vehicles, not only driven by the increasing customer demand for vibro-acoustic comfort, but also by the tightening legal regulations regarding noise and vibration emissions and immissions. Since noise and vibration as functional performance attributes often conflict with other attributes, such as weight and CO2 emission, concurrent design and analysis procedures are required. Such processes involve multi-attribute optimisation and are facilitated by the use of Computer Aided Engineering (CAE) tools. Also, there is an increasing trend towards virtual prototyping to reduce costs and development times. As a result, good CAE tools are essential in modern vehicle design. Ideally CAE tools would be applicable in the whole frequency range of interest, which is the audio-frequency range. In practice specific methods are applicable in a limited frequency region. A class of deterministic “low frequency” methods is both well developed and well established. At “high frequencies” energy based methods are valuable, but less well-established. There is however a “mid-frequency” gap in current modelling capabilities: too high for deterministic and too low for energy based tools. This is important, since it strongly affects product performance and competitiveness. The lack of CAE tools for mid-frequency issues forms the target for this collaborative project. In this project a well balanced consortium of both academic and industrial partners will develop robust CAE tools, applicable for the analysis of mid-frequency noise and vibration problems. In a second stage, these tools will be applied on industrial problems, filling the currently existing gap. A third important aspect of the project is the dissemination of mid-frequency analysis and modelling skills throughout the EU engineering community to spread crucial knowledge and skills in strengthening EU transportation vehicle competitiveness.'

Introduzione (Teaser)

Vibration and noise can impede the regulatory certification of vehicles and compromise passenger comfort. New simulation tools developed by EU-funded scientists promise to minimise the effects, providing a competitive edge for related industries.

Descrizione progetto (Article)

Computer-aided engineering (CAE) tools have become standard fare for virtual prototyping in order to reduce time and cost of development. They are particularly useful for multi-attribute design considerations, such as when optimal design for noise and vibration reduction conflicts with optimal design for reduction of weight and carbon dioxide (CO2) emissions.

Well established deterministic CAE tools exist to model low-frequency (LF) noise and vibrations, and some energy-based (stochastic or probabilistic) high-frequency (HF) methods are also available. In order to fill the mid-frequency (MF) modelling gap, scientists initiated the EU-funded project MID-MOD.

During the first reporting period, scientists evaluated five deterministic (typically used for LF) and five probabilistic (typically used for HF) methodologies currently at the laboratory stage for their potential applicability to the MF vibration range problem in industry. Models are being assessed for their ability to adequately represent component, subsystem and full vehicle scenarios in both interior and exterior noise generation. Model formulations and validation are ongoing.

Application scenarios for the evaluation of interior and exterior acoustic truck issues have been defined. The latter will evaluate acoustic radiation and emission in the MF range of a truck silencer using a chosen deterministic theoretical method that will be validated with experimental results. Experimental measurements regarding internal car noise applications have commenced. The same deterministic method applied to the truck will be used to model acoustic radiation in the MF range from the signal horn. Component and subsystem levels have been defined for study of interior rail noise.

Noise and vibration have important effects on consumer satisfaction and regulatory certification, translating to impact on the competitive position of the transport sector. MID-MOD is providing important CAE simulation tools that are currently lacking in order to reduce the time and cost of new product development while enhancing the overall performance of novel designs.