Development of Mathematical Model of Heat Conductivity of Dry and Wet Mineral Wool

It is known that the moisture content of materials in the enclosing structures is not constant throughout the year, whereby the heat-shielding qualities of the enclosures change. The calculated parameters of the humid operating conditions A and B do not characterize the real heat loss of buildings. Design parameters of humidity operating conditions A and B do not characterize the real heat loss of buildings. Based on this, the thermal conductivity of mineral wool was studied depending on its porosity and humidity. Experimentally determined values of thermal conductivity of mineral wool were analyzed using the theory of effective media. Mineral wool was considered as a mixture of three phases: solid (basalt fibers), gaseous (air) and liquid (water). A mathematical model of thermal conductivity of mineral wool was developed, which makes it possible to estimate the thermal conductivity in wide density and humidity intervals by one experimental determination of thermal conductivity for a sample of one selected density and to construct a graphical dependence of thermal conductivity for mineral wool of any density in a wide range of its humidity.

V.N. KUPRIYANOV, Doctor of Sciences (Engineering), Corresponding Member of RAACS (This email address is being protected from spambots. You need JavaScript enabled to view it.)
A.M. YUZMUHAMETOV, Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.)

Kazan State University of Architecture and Engineering (1, Zelenaya Street, Kazan, 420043, Russian Federation)

1. Beregovoi A.M., Beregovoi V.A. Temperature-moisture state of external enclosure structures in the conditions of phase transitions of moisture and aggressive impact of the environment. Regional’naya arhitektura i stroitel’stvo. 2017. No. 3 (32), pp. 99–104. (In Russian).
2. Kupriyanov V.N., Safin I.Sh. Influence of external facing layers on processes of condensation of vaporous moisture in the protecting designs. Privolzhskij nauchnyj zhurnal. 2014. No. 1, pp. 46–51. (In Russian).
3. Ivantsov А.I., Kupriyanov V.N. The mode of operation of the multilayered wall protecting designs as basis of forecasting of their service life. Izvestiya KGАSU. 2014. No. 3 (29), pp. 32–40. (In Russian).
4. Petrov А.S., Kupriyanov V.N. Moisture condition of enclosing structures with due regard for variable value of vapor permeability of materials. Stroitel’nye Materialy [Construction Materials]. 2016. No. 6, pp. 40–44. (In Russian).
5. Kupriyanov V.N., Yuzmukhametov А.M., Safin I.Sh. Research of regularities of transfer of water vapor through a protection on model samples. Vestnik PTO RААSN. 2018. No. 21, pp. 169–175. (In Russian).
6. Pavlenko N.V., Pastushkov P.P., Kharkhardin A.N., Voitovich E.V. Study of relationship of structural and steam curing characteristics in nanostructured binder based foam concrete. Vestnik SibADI. 2016. No. 6 (52), pp. 80–86. (In Russian).
7. Pastushkov P.P., Pavlenko N.V., Korkina E.V. The use of a nominal definition operational humidity of insulating materials. Stroitel’stvo i rekonstrukciya. 2015. No. 4 (60), pp. 168–172. (In Russian).
8. Milena Jiricková, Zbysek Pavlik, Lukas Fiala, Robert Cerny. Thermal conductivity of mineral wool materials partially saturated by water. International Journal of Thermophysics. 2006. Vol. 27. Iss. 4, pp. 1214–1227. DOI: 10.1007/s10765-006-0076-8
9. Drochytka R., Zach J., Hroudova J. Non-destructive testing of influence of moisture on properties of autoclaved aerated concrete. E-Journal of Nondestructive Testing. 2011. URL: http://www.ndt.net/article/ndtnet/2011/36_Zach.pdf (дата обращения: 05.05.2018).
10. Antepara I., Fiala L., Pavlik Z. Moisture dependent thermal properties of hydrophilic mineral wool: application of the effective media theory. Materials Science (Medziagotyra). 2015. Vol. 21. No. 3, pp. 449–454.