Mathematical description of the operating temperature in regimes for autoclave steaming and subsequent air conditioning of wood

Abstract

ABSTRACT A mathematical description of the operating temperature of each of the five constituent stages of regimes for autoclave steaming and subsequent air conditioning of wood has been proposed. This description has been included in the boundary conditions of two coupled own non-stationary temperature-energy models of the autoclave steaming process of wooden prisms intended for veneer production. Using these models, calculation of the durations of the initial part and of the whole regimes for steaming of beech prisms have been carried out. The variables were an initial wood temperature of 0 and –20 °C, moisture content of 0.4, 0.6, and 0.8 kg·kg−1, and cross-section dimensions of the prisms 0.3 × 0.3 m and 0.4 × 0.4 m; steaming autoclave with a diameter of 2.4 m, length of 10.6 m, and loading level of 40, 50, and 60% at limited thermal power of 500 kW suplied to the autoclave. The simulations carried out using Visual Fortran showed a good agreement of the proposed mathematical description with many previously obtained experimental results and confirmed the possibility of its being applied in the boundary conditions of various non-stationary models of autoclave treatment processes (steaming, impregnation, desired property modification) of wood and other materials.