Bottom-up approach for microstructure optimization of sound absorbing materials
نویسندگان
چکیده
منابع مشابه
Bottom-up approach for microstructure optimization of sound absorbing materials.
Results from a numerical study examining micro-/macrorelations linking local geometry parameters to sound absorption properties are presented. For a hexagonal structure of solid fibers, the porosity phi, the thermal characteristic length Lambda('), the static viscous permeability k(0), the tortuosity alpha(infinity), the viscous characteristic length Lambda, and the sound absorption coefficient...
متن کاملEfficient finite element approach for structural-acoustic applications including 3D modelling of sound absorbing porous materials
This thesis presents efficient finite element solutions of poro-elasto-acoustic coupled problems using modal-based approaches adapted to non conservative problems, combined with an interpolation method in frequency, based on Padé approximants. The performance of the proposed methods and their combination is demonstrated on several 1D to 3D coupled problems. Conclusions are drawn to provide indi...
متن کاملOn measurement of mechanical properties of sound absorbing materials
This paper is an overview of quasistatic measurement technique used to determine mechanical properties of sound absorbing materials. Experimental context and behaviour of polymer foam and rock wool are summarized. Concerning parameters are: static and dynamic strains, dynamic effects such as skeleton resonance and coupling with saturating fluid. Material anisotropy and frequency dependance of c...
متن کاملSemantic Query Optimization for Bottom-Up Evaluation
Semantic query optimization uses semantic knowledge in databases (represented in the form of integrity constraints) to rewrite queries and logic programs to achieve eecient query evaluation. Much work has been done to develop various techniques for optimization. Most of it, however, is applicable to top-down query evaluation strategies. Moreover, little attention has been paid to the cost of th...
متن کاملSchlieren photography to study sound interaction with highly absorbing materials.
Strong absorption of sound is often caused by the conversion of sound energy into heat. When this happens, it is not possible to study the interaction of sound with the absorbing material by means of reflected sound characteristics, because there is no reflected sound. Detecting for example the distance that sound travels in a strongly absorbing material, can be done by heat detection systems. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Journal of the Acoustical Society of America
سال: 2008
ISSN: 0001-4966
DOI: 10.1121/1.2945115