DIELECTRIC PROPERTIES OF MATERIALS AND MEASUREMENT TECHNIQUES
- 1 January 1990
- journal article
- research article
- Published by Taylor & Francis in Drying Technology
- Vol. 8 (5) , 1123-1142
- https://doi.org/10.1080/07373939008959939
Abstract
The dielectric properties of materials are defined, and the nature of their dependence on moisture content, frequency of the applied electric field, temperature of the material, and density of particulate materials is discussed. Dielectric properties of liquid water are summarized. The influence of moisture content, frequency, temperature, and density on the values of the dielectric constant and loss factor, real and imaginary parts of the relative complex permittivity, respectively, are illustrated for several different kinds of materials. Examples include dielectric properties for the cereal grains corn and wheat, pecans, and pulverized coal. Techniques for the measurement of dielectric properties of materials at high frequencies and microwave frequencies useful for dielectric heating and drying applications are discussed briefly, and numerous publications describing these methods in greater detail are cited for reference.Keywords
This publication has 31 references indexed in Scilit:
- Dielectric properties of selected minerals at 1 to 22 GHzGeophysics, 1989
- Composite model of the complex permittivity of cereal grainJournal of Agricultural Engineering Research, 1989
- Automatic System for Dielectric Properties Measurements from 100 kHz to 1 GHzTransactions of the ASAE, 1989
- Automatic material characterization at microwave frequenciesIEEE Transactions on Instrumentation and Measurement, 1988
- A Mathematical Model for Estimating the Dielectric Constant of Hard Red Winter WheatTransactions of the ASAE, 1985
- Throughput Variables for Rotary Extrusion MaceratorsTransactions of the ASAE, 1981
- Dielectric relaxation spectroscopy of liquids: frequency domain and time domain experimental methodsJournal of Physics E: Scientific Instruments, 1980
- Frequency and moisture dependence of the dielectric properties of hard red winter wheatJournal of Agricultural Engineering Research, 1976
- Electrical Properties of Agricultural Products-A Critical ReviewTransactions of the ASAE, 1973
- A Bridge Method for Dielectric Measurements of Grain and Seed in the 50- to 250-MHz RangeTransactions of the ASAE, 1970