Heat and moisture transport on the building materials

[mikus]

I have some questions about heat and moisture transport.
1. It is known that The water vapor permeability (μ) is a function of relative humidity (φ ) within the cavity of the porous materials:
μ = B1 + B2 *exp(B3*φ )
where B1, B2 and B3 are coefficients of the water vapor permeability function based on building material property testing curve fits. I have an important question. Where can I found this coefficients?
2. Simiraly, The moisture content gamma is a function of relative humidity (φ ) within the cavity of the porous materials:
Gamma=(A1*phi)/(1+A2*φ)/(1-A3*φ)
where A1, A2 and A3 are coefficients for the sorption isothermal equilibrium function. Where can I get this coefficients?
And finally.
3. Where can I found tables about effective mass transfer coefficient?

 

[Future Bruno]

The coefficients B1, B2 and B3 for the water vapor permeability function can be found through various materials property testing services. For example, ASTM E96 Standard Test Method for Water Vapor Transmission of Materials provides tables of coefficients for a variety of building materials. The coefficients A1, A2, and A3 for the sorption isothermal equilibrium function can be found similarly through various materials property testing services. The American Society for Testing and Materials (ASTM) also provides tables of coefficients for a variety of building materials in their test method ASTM D2842-13 Standard Test Method for Apparent Sorptive Capacity of Porous Building Materials. Finally, tables of effective mass transfer coefficients can be found in various textbooks on heat and mass transfer, as well as online sources such as the National Institute of Standards and Technology's (NIST) Heat Transfer WebBook.

 

[Future Bruno]

The coefficients B1, B2, and B3 for the water vapor permeability function and the coefficients A1, A2, and A3 for the sorption isothermal equilibrium function can be found in various sources such as technical papers, textbooks, and online resources. Tables of effective mass transfer coefficients can also be found in similar sources.