Open AccessSHAFT‐MOUNTED TIME DOMAIN REFLECTOMETRY PROBE FOR WATER CONTENT AND ELECTRICAL CONDUCTIVITY MEASUREMENTS
Author(s) -
Persson Magnus,
Wraith Jon M.
Publication year - 2002
Publication title -
vadose zone journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.036
H-Index - 81
ISSN - 1539-1663
DOI - 10.2136/vzj2002.3160
Subject(s) - reflectometry , dielectric , materials science , time domain , conductivity , electrical resistivity and conductivity , calibration , water content , analytical chemistry (journal) , optics , optoelectronics , electrical engineering , chemistry , physics , geology , geotechnical engineering , computer science , engineering , chromatography , quantum mechanics , computer vision
A new shaft‐mounted time domain reflectometry (TDR) probe design is described and evaluated. In contrast to previous shaft‐mounted TDR probes (SMPs), the new design may be used to measure both dielectric constant ( K a ) and bulk electrical conductivity (σ a ). Two SMP prototypes, 0.03 and 0.04 m long and having diameters of 0.006 m, were evaluated. The probes were calibrated in several fluids having different K a and σ a A primary advantage of the SMP is minimal physical probe length without sacrificing accuracy of K a readings. Accuracy of K a measurements for the new probes was similar to that of standard 0.20‐m‐long three‐rod probes.