Premium
Numerical Modeling of a Capacitance Probe Response
Author(s) -
Rosny G.,
Chanzy A.,
Pardé M.,
Gaudu J-C.,
Frangi J-P.,
Laurent J-P.
Publication year - 2001
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj2001.65113x
Subject(s) - capacitance , dielectric , capacitance probe , mechanics , electrode , finite element method , materials science , constant (computer programming) , numerical analysis , numerical modeling , soil water , computational physics , physics , thermodynamics , mathematics , optoelectronics , mathematical analysis , geology , computer science , soil science , quantum mechanics , programming language , geophysics
Capacitance sensors are one of the common means of characterizing the soil dielectric constant. Their design depends on their expected applications. In particular, the electrode geometry has a critical influence on the extension of the probed region. Moreover, the soil may not always be viewed as a medium of statistically uniform dielectric constant (because of packing effects, air sheath in the vicinity of the electrodes, stones). Numerical modeling for the behavior of a particular probe was developed. It is based on solutions of the Maxwell's equations in the quasi‐static approximation, by a finite element method. This modeling was compared with laboratory measurements in various media (air, ethanol) where heterogeneity was inserted in the vicinity of the electrode. The numerical model reproduces very well the probe response when millimetric scale perturbations were introduced. The numerical model appears to be a promising tool to investigate more deeply the capacitance probe measurements, for instance the extension of the measurement volume or the significance of measurements in highly structured soils.