Influence of oscillation climate on cinetics and drying quality of spruce wood

Kinetiko in kakovost sušenja smrekovine (Picea abies (L) Karst.) smo raziskovali pri 3 različnih pogojih sušenjas standardnim postopkom z blago, ostro in oscilacijsko klimo. Uporabili smo stranske deske debeline 25 mm in jih osušili na končno vlažnost 11 %. Pri vseh postopkih smo z intervalnim odvzemom merili: povprečno vlažnost, vlažnostni gradient in zaskorjenje. Končna vlažnost osušenega lesa je bila pri vseh 3 eksperimentih podobna z zanemarljivim odstopanjem. Najvišji vlažnostni gradient smo izmerili pri standardnem programu z ostro klimo, sledil je standardni program z oscilacijsko klimo, najmanjši pa je nastal pri programu z blago klimo. Pri sušenju v oscilacijskih in ostrih klimatskih pogojih se je pojavila zaskorjenost. Stopnja zaskorjenosti pri ostri klimi je bila višja kot pri oscilacijski. Delovne hipoteze, da oscilacija klime omogoča kakovostnejše sušenje, nismo v celoti potrdili.Drying kinetics and drying quality of spruce wood (Picea abies (L.) Karst.) were investigated at 3 different drying conditions. Drying was performed using a standard procedure with mild, sharp and with oscillatory drying climatic conditions. 25 mm thick side boards were dried till they reached final moisture of 11 %. All procedures were compared by intermittent removal of samples and by measuring the following properties of wood: average moisture content, moisture gradient and casehardening. The final value of the dried wood moisture in all 3 experiments was the same with negligible variations. The maximum moisture content gradient was gained using a drying procedure with the sharp climate, medium by oscillatory climate, and the lowest in the standard program with a mild climate. The casehardening occurred when dried in oscillating and sharp climatic conditions. Rate of casehardening in sharp climate was higher than in the oscillatory climate. The working hypothesis that the oscillating climate enables better drying was not completely confirmed