Experimental Determination of Heat and Moisture Transport Properties of AAC in the Range of Subzero to Room Temperatures

• Published in: International journal of thermophysics Vol. 40; no. 1; pp. 1 - 11
• Main Authors: Kočí, Jan, Maděra, Jiří, Jerman, Miloš, Černý, Robert
• Format: Journal Article
• Language: English
• Published: New York Springer US 2019; Springer Nature B.V
• Subjects: 20th Symposium on Thermophysical Properties; Aeration; Autoclaving; Building materials; Classical Mechanics; Condensed Matter Physics; Construction materials; Diffusivity; Geophysics; Heat conductivity; Heat transfer; Industrial Chemistry/Chemical Engineering; Mathematical analysis; Moisture content; Parameters; Permeability; Physical Chemistry; Physics; Physics and Astronomy; Porous materials; Specific heat; Temperature; Temperature dependence; Temperature effects; The 20th Symposium on Thermophysical Properties; Thermal conductivity; Thermodynamics; Water vapor; Thermal conductivity; Autoclaved aerated concrete; Temperature; Water vapor diffusion permeability; Moisture diffusivity; Moisture
• ISSN: 0195-928X; 1572-9567
• DOI: 10.1007/s10765-018-2464-2

Thermal and hygric parameters of porous building materials are often determined as single values only. Neglecting their dependence on temperature and moisture can though lead to higher uncertainties in hygrothermal and energy-related calculations. In this paper, thermal conductivity, specific heat capacity, water vapor diffusion permeability and moisture diffusivity of autoclaved aerated concrete are measured as functions of both temperature and moisture in the ranges characteristic for their application in building structures. Experimental results show temperature as a very significant factor affecting all parameters, but its combination with moisture in different forms is even more important. The combined effects of temperature and moisture are most remarkable for thermal conductivity and moisture diffusivity, which can vary within a range of two orders of magnitude. The water vapor diffusion permeability increases with decreasing temperature despite the decreasing amount of water vapor diffused through the sample. The specific heat capacity increases continuously with both temperature and moisture.