Tinianov, B: Predicting Thermal Conductivity Using Acoustic

This monograph describes a novel technique for the prediction of the thermal performance of low density fiber glass insulation and other related fibrous insulation materials using anacoustic apparatus. The project aim is to create a technology for in situ quality control testing of such fiber glass batts during production yielding substantial cost savings for the manufacturer. The project scope is twofold - the development and validation of an experimental acoustic technique, and a model of the relationship between the heat transfer and acoustical attenuation. Experimental laboratory results show excellent correlation between the thermal conductivity and the propagation constant. Correlation of calculated propagation constant magnitude versus measured thermal conductivity gave an R2 of 0.94 for the range typically manufactured fiber glass batt materials. Given the promise of such highly correlated measurements, the acoustic technique could be used to continuously predict the thermal conductivity of the material during its production, replacing current off-line methods. Test cycle time is reduced from tens of minutes to seconds.