Computing the Heat Balance of Boiling Pits during Defrosting of Frozed Logs in them

An approach for computing the heat balance of boiling pits during defrosting of logs in them intended for veneer production has been presented. With the help of our own non-stationary model, the defrosting times of beech logs with a diameter of 0.4 m, initial temperature of -10 °C, and moisture content of 0.6 kg.kg
⁻¹
were determined at water temperatures in the pit equal to 70, 80 and 90 °C. Using the determined logs' defrosting durations and the mentioned approach, the change in the total energy required to completely defrost the logs in the pit from their initial average mass temperature of -10 °C to 0 °C and that required for each of the individual components of the heat balance was calculated. Computer simulations were conducted for a concrete pit with overall dimensions 8.0 × 2.6 × 2.5 m, working volume of 20 m
³
, and a degree of filling with logs equal to 25, 50, and 75%. The approach can be applied to compute heat balances of pits both during defrosting only and during complete defrosting and subsequent boiling of frozed logs to a desired final average mass temperature required for the mechanical processing of the plasticized logs.