Determination of Hygrothermal Properties for Building Materials using Inverse Modeling Techniques

The paper presents the development of a method that determines building material and surface properties using relative simple and low-budget experiments, with the following conditions: (I) Constrained: the material is located in building constructions and only non destructive measurements are allowed. (II) Unconstrained: the material if is freely available for optimal testing. The latter comprehends an optimal design of an experimental set up for smart determination of heat and moisture properties using both normal and inverse modeling techniques. The preliminary results show that the inverse modeling method using MatLab is almost perfectly capable of reproducing the material parameters using the 3D Comsol simulations as input. However, using the actual measurements as input for the inverse modeling provides unsatisfactory results so far. It is concluded that the suggested methodology of the inverse problem technique seems promising for estimating material properties but requires that: (1) All measurements errors must be known; (2) The (measured) signals itself should deliver enough input power into the system; (3) The simulated objective data should be sensitive enough for changes in material properties.