EFFECTS OF SIMULATED WOOD DRYING SCHEDULES ON DRYING TIME AND ENERGY CONSUMPTION AT AN EXPERIMENTAL KILN

Abstract

Wood conventional timber drying is the process in which the heat transfer from the warm air to wood and the mass transfer from wood to air are encountered. It is difficult to obtain exact solutions of the differential heat and mass transfer equations applied to the drying process, due to many process variables, therefore numerical modeling gives important information about the process. We used in the paper a simulation model, developed for a single board drying, in order to obtain how the drying time and energy consumption are influenced by 64 different drying schedules as combinations of three factors, air temperature (50-80oC), velocity (0.5-0.8m/s) and relative humidity (20-35%), each at four levels. The relationship between the factor settings and the responses (drying time and energy consumption, respectively) was acquired by means of the multiple quadratic regression model. It was found that the temperature had the main effect on both, drying time and energy consumption. Instead, the velocity had very little effect on these ones.