CALCULATION OF THE THERMAL ENERGY AND ITS COMPONENTS REQUIRED FOR THAWING LOGS
Keywords:
frozen logs, frozen bound water, frozen free water, thawing, thermal energyAbstract
An approach for calculating the thermal energy and its components required for thawing logs intended for veneer production is proposed. The approach is based on the use of two personal mathematical models. The influence of all combinations between 5 values of the initial wood temperature from −1 °C to −40 °C and 3 values of the wood moisture content above the hygroscopic range (0.4 kg·kg-1, 0.6 kg·kg-1, and 0.8 kg·kg-1) on the thermal energy and its four components required to thaw beech logs with a diameter of 0.4 m at operating temperature of the heating medium of 80 °C was investigated. The obtained results show that this energy changes in the range from 31.66 kWh·m-3 (at −1 °C and 0.4 kg·kg-1) to 95.36 kWh·m-3 (at −40 °C and 0.8 kg·kg-1). The approach could be applied to determine the energy required to thaw various frozen capillary-porous materials in practice.
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