This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Carpet Hybrid Foam Spacer: An Ultra-Absorbing Lightweight Floor Insulator
Technical Paper
2016-01-1851
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The noise treatments weight reduction strategy, which consists in combining broadband absorption and insulation acoustic properties in order to reduce the weight of barriers, depends strongly on surface to volume ratio of the absorbing layers in the reception cavity. Indeed, lightweight technologies like the now classical Absorber /Barrier /Absorber layup are extremely efficient behind the Instrument Panel of a vehicle, but most of the time disappointing when applied as floor insulator behind the carpet.
This work aims at showing that a minimum of 20 mm equivalent “shoddy” standard cotton felt absorption is requested for a floor carpet insulator, in order to be able to reduce the weight of barriers. This means that a pure absorbing system that would destroy completely the insulation properties and slopes can only work, if the noise sources are extremely low in this specific area, which is seldom the case even at the rear footwells location. The proposed Carpet hybrid foam spacer technology is answering to the question by using the hybrid foam-foam 3D solution, applied as floor insulator with encapsulated rigid EPS or EPP foam spacers in the PUR foam spring layer, depending on the overall available thicknesses.
The ultra-absorbing properties are obtained thank to the upper dense (90 to 140 kg/m3), resistive, tortuous and stiff foam layer having an average thickness of more than 15 mm up to 20 mm. The latter layer is also working as an equivalent barrier of its weight per unit area thank to its bending stiffness and to the airtight hybrid intermediate interpenetration layer between the upper absorbing and lower insulating foam layers (18 dB/oct slopes). All existing floor insulator technologies will be compared to one another using the Finite Transfer Matrix Method, as well as poroelastic finite elements method for various overall thicknesses from 30 mm to 100 mm. A Ray-Tracing model will be used as well, in order to quantify the absorption effects at ear point of this floor carpet insulator.
Authors
Topic
Citation
Duval, A., Hoang, M., Marcel, V., and Dejaeger, L., "Carpet Hybrid Foam Spacer: An Ultra-Absorbing Lightweight Floor Insulator," SAE Technical Paper 2016-01-1851, 2016, https://doi.org/10.4271/2016-01-1851.Also In
References
- Duval , A. Faurecia acoustic light-weight concept Congrès SIA Confort automobile et ferroviaire Le Mans, France 2002
- Duval , A. , Rondeau , J-F. , Deshayes , G. , Lhuillier , F. et al. Generalized light-weight concept: a comprehensive acoustic package weight reduction strategy Congrès SIA Confort automobile et ferroviaire Le Mans, France 2006
- Zhang , Ch. , Monet-Descombey , J. , Lhuillier , F. , Duval , A. et al. Numerical and experimental study of light-weight concept under automobile applications conditions SAE Styrian Noise Vibration & Harshness Congress Graz, Austria 2008
- Duval , A. , Rondeau , J-F. , Dejaeger , L. , Lhuillier , F. et al. Generalized Light-Weight Concepts: A New Insulator 3D Optimization Procedure 2013-01-1947 SAE NVC Conference Grand Rapids (MI) 2013
- Duval , A. , Rondeau , J-F. , Lhuillier , F. , Deshayes , G. et al. Faurecia vehicle acoustic synthesis method: A hybrid approach to simulate interior noise of fully trimmed vehicles Congrès SIA Confort automobile et ferroviaire Le Mans, France 2004
- Duval , A. , Rondeau , J-F. , Bossart , R. , Gagliardini , L. et al. Vehicle acoustic synthesis method 2nd generation: an effective hybrid simulation tool to implement acoustic lightweight strategies Journée SFA/Renault/SNCF Guyancourt, France 2005
- Rondeau , J-F. , Duval , A. , Chanudet , P. , Gagliardini , L. et al. Vehicle acoustic synthesis method: run-up simulation and 3D design of weight reduction technologies Congrès SIA Confort automobile et ferroviaire Le Mans, France 2008
- Duval , A. and Bischoff , L. Stiff textiles or felts glued on light impervious layers: a new "green" light septum fiber technology SAPEM 2011 conference Ferrara, Italy 2011
- Duval , A. , Dejaeger , L. and Marcel , V. Optimization and 3D design of a dual density stiff hybrid injected foam-foam insulator SAPEM Conference Stockholm, Sweden 2014
- Allard , J.-F. and Atalla , N. Propagation of sound in porous media 2nd John Wiley & Sons 2009
- Atalla , N. , Panneton , R. and Debergue , P. A mixed displacement-pressure formulation for poroelastic materials J. Acoust. Soc. Am. 104 3 1444 1452 1998
- Omrani , A. , Mebarek , L. and Hamdi M.A Transmission loss modeling of trimmed vehicle components ISMA Leuven 2006
- Dauchez , N. , Sahraoui , S. and Atalla , N. Convergence of poroelastic finite elements based on Biot displacement formulation J. Acoust. Soc. Am. 109 1 33 40 2001
- Duval , A. , Dejaeger , L. , Bischoff , L. , and Morgenstern , C. Trim FEM Simulation of a Headliner Cut Out Module with Structureborne and Airborne Excitations SAE Technical Paper 2012-01-1524 2012 10.4271/2012-01-1524
- Gaudaire , F. et al. Une méthode de tirs de rayon pour caractériser la propagation sonore dans les volumes complexes Congrès SIA Confort automobile et ferroviaire Le Mans, France 2000