The most of methods for solving inverse problems of moisture transport are based on measuring moisture profiles in a 1-D approximation, u(x,t). The basic experiment setup is very common. A rod-shaped specimen has one of its face sides in a direct contact with water, and the other face is left free in contact with the surrounding air. The lateral sides are water- proof and vapor-proof insulated to ensure 1-D moisture transport. The moisture profiles in selected times are then measured by a proper method, as for instance NMR, X-ray attenuation, ¦Ă-ray attenuation, capacitance, microwave, etc.

In the practical solution of inverse problems of moisture transport, transient methods are usually preferred because the steady-state methods are very time consuming, the requirements for vapor tightness are higher than for the transient methods, and in addition, for some materials it is not possible to get any results because the steady state moisture profile is in the form of a constant moisture distribution. In this paper, we will show four selected transient methods which are commonly used in our laboratory.

Survey of four (4): Methods for solving inverse problems for moisture transport from moisture profile.

Matano method

Gradient method:

Difference method: Cerny R., Toman J., 1998, Determination of temperature- and moisture-dependent thermal conductivity by solving the inverse problem of heat conduction

Double integration method

Similar References

CERNY, R.: Thermal and Hygric Properties of Building Materials under Nonstandard Conditions. [PN] : Properties of Building Materials : Glasgow, 09.04.1997. Building Research Establishment, Glasgow: GB1997

CERNY, R. - CHAB, V. - PRIKRYL, P.:

CERNY, R. - DRCHALOVA, J. - TOMAN, J.: Numerical Analysis of Methods for Determining the Diffusivity of Liquid Moisture in Building Materials. [PN] : CIB W40 Meeting : Kyoto, 09.10.1997. Osaka Sangyo University, JP1997

CERNY, R. - SEMERAK, P.: An Analysis of Methods for Solving the Inverse Problems of Moisture Transport in Porous Materials. [RN] : In: Workshop 97. Part I. Prague : Czech Technical University. 1997. p. 45-46.

CERNY, R. - TOMAN, J.: A Difference Method for Determining the Thermal Conductivity of Porous Materials in Wide Temperature Range. [RP] : In: High Temperatures, High Pressures. 29, Vol.1 (1997), p. 51-57.

CERNY, R. - TOMAN, J.: Measuring and Calculating the Thermal and Hygric Properties of Insulating Building Materials over Wide Temperature and Moisture Ranges. [RN] : In: Insulation Materials. Testing and Applications. R. S. Graves. - 1. Ed.West Conshohocken : ASTM. 1997. p. 524-535. - ISBN 0-8031-2409-0.

CERNY, R. - TOMAN, J.: Solution of Inverse Problems of Heat Conduction in Building Materials. [RN] : In: Numerical Methods in Thermal Problems. Vol. 10. - 1. Ed. Swansea : Pineridge Press. 1997. p. 811-820. - ISBN 0-906674-89-1.

• liquid transport, moisture diffusivity
• measurement: hygrothermal properties : moisture diffusivity from moisture profiles
• measurement: moisture content
• surveys, reviews, statistics : determination of moisture diffusivity

1. Water and water vapor penetration through coatings  

1. A comparison of different techniques to quantify moisture content profiles in porous building materials
2. Determination of the liquid water diffusivity from transient moisture transfer experiments  

1. A comparison of different techniques to quantify moisture content profiles in porous building materials
2. A transient method for measuring the water vapor diffusion in porous building materials
3. Determination of temperature- and moisture-dependent thermal conductivity by solving the inverse problem of heat conduction
4. Determination of the liquid water diffusivity from transient moisture transfer experiments
5. Water and water vapor penetration through coatings