It is proposed to apply a method for identifying thermal effusivity in order to monitor the percolation of water in a soil by means of a noninteger order model. This model is expressed in the form of a linear relation connecting the fractional derivatives of the temperature at a point of the system to the fractional derivatives of the stress applied, namely a flux. These derivatives are replaced by their discrete definitions and the model coefficients are identified from experimental measurements by a method of linear least squares. Flux sensors are used to measure the flux and temperature simultaneously in the access plane to the system, enabling the thermal impedance to be calculated. The study is made up of two parts: The first part consists in establishing in the laboratory a correlation between the effusivity and water content of a sample of ground studied by traditional methods. The second part constitutes the in situ tests, where with the flux sensors and the application of the method, the effusivity of the ground can be estimated and thus the water content deduced.
ASJC Scopus subject areas
- Materials Science (miscellaneous)
- Ceramics and Composites
- Polymers and Plastics