Equivalent Circuit Modeling of the Dielectric Properties of Rubber Wood at Low Frequency
Keywords:
Dielectric constant, dielectric loss factor, moisture content, universal capacitance, susceptibility, diffusive, quasi-dcAbstract
Dielectric properties of rubber wood were studied at various moisture contents and grain directions at low frequencies from 10-2 to 105 Hz. Results showed that the moisture content of wood affected the dielectric properties considerably. Dielectric data at different anisotropic directions, i.e., longitudinal, radial, and tangential and at various moisture contents were modeled using universal capacitance. The equivalent circuits for different dielectric processes observed in wood were expressed by the combinations of diffusive, quasi-dc elements together with nondispersive capacitance and resistance. Three equivalent circuits for wood with moisture contents-a) above fiber saturation point, b) below fiber saturation point, and c) very low moisture content or oven-dried wood-are obtained for three grain directions. The experimental data are in close agreement with the value obtained from equivalent circuit.References
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