Recommendations for the Determination of the Dielectric Properties of Wood and Wood-Based Materials and for Their Use in Calculations

Abstract

The wide spectrum and intricate character of the correlations between the dielectric properties of wood and wood density, moisture content, temperature, orientation of the vector of the electric field strength relative to the fiber direction, and frequency make it difficult to calculate the interactions between electromagnetic fields and wood. These calculations are required for production processes, designing production facilities, as well as for the development of measuring instruments. In some cases, it is necessary to know the dielectric characteristics at fixed values of moisture content and temperature. During the heating and drying treatment of wood, its temperature or moisture content (or both) change, and usually the average values of the dielectric parameters should be used. Therefore, in order to ensure reliable results and conclusions, it is necessary to determine the correct values of the dielectric properties of a given material.