Structural Acoustics and Vibration Session 1pSA: Measurement and Modeling of Structures with Attached Noise Control Materials II 1pSA3. Investigations on the sensitivity of the relationships between sound absorption characteristics and microstructure related parameters for polyurethane foams
نویسندگان
چکیده
Straightforward semi-phenomenological models have been developed for highly porous polyurethane foams to predict the macroscopic nonacoustic parameters involved in the classical Johnson-Champoux-Allard model (i.e., porosity, airflow resistivity...) from microstructure properties (i.e, strut length, strut thickness and reticulation rate). These microstructure properties are measured using sophisticated optical methods (i.e., optical microscope, SEM) and a large variability can be observed due to great complexity of the 3D microstructure; variability which also depends on the precision of the measurement device. This work investigates how the variability associated with the model inputs affects the model outputs (i.e., non-acoustic parameters, surface impedance and sound absorption coefficient). The sensitivity analysis is based on the Fourier Amplitude Sensitivity Test (FAST). It helps quantify the correlation between the input parameters and identify the parameters contributing the most to output variability, thus requiring precise measurement. This study illustrates the preponderant impact of the reticulation rate (i.e, open pore content) on acoustic performances and guides the user on the required optical measurement device.
منابع مشابه
Effect of non-acoustic properties on the sound absorption of polyurethane foams
In this paper the influence of non-acoustic properties on the sound absorption coefficient of polyurethane foams as a porous medium is investigated. Biot’s equations with transfer matrix method, as the solution approach are employed to evaluate the sound absorption coefficient of selected polyurethane foams. The major issue is the dependency of non-acoustic properties on each other which makes ...
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