MATHEMATICAL MODELS FOR THERMAL CONDUCTIVITY- DENSITY RELATIONSHIP IN FIBROUS THERMAL INSULATIONS FOR PRACTICAL APPLICATIONS

Relationship between thermal conductivity (λt) and density (ρ) of mineral wool insulations has a wide band of measured data, follows some form of median curve which is called reference curve. Departures from this curve are mainly due to the fact that manufacturing conditions change. But the deviation from the curve should be in a limited range because it will affect the quality conformity. With finding t λ = f(ρ) as a reference curve and using routine test results it is possible to note the changes in quality of the products. On the other hand λt may be evaluated indirectly using ρ measurements and the established reference curve for a specific production line. For finding the suitable model for λt = f(ρ), a large amount of data was studied in this article. Different semi-empirical models were presented and statistically compared with the experimental results to evaluate the best one.