Address: 17 Naberezhnaya Severnoy Dviny, Arkhangelsk 163002 Russian Federation. Northern (Arctic) Federal University named after M.V.Lomonosov. Office 1425

Phone / Fax: (818-2) 21-61-18



Kinetics of Drying of Wood Profile Blanks

Версия для печати
Creative Commons License
These works are licensed under a Creative Commons Attribution 4.0 International License.

P.V. Biley, R.A. Rokun'

Complete text of the article:

Download article (pdf, 0.4MB )






The drying process of profile blanks of solid wood has a number of features. First of all it is a variable cross-section along the length of a blank, which poses a number of challenges to form the staples or packages, to select the modes, technologies and drying equipment. The beechwood is selected as an experimental material, which is often used for firewood. The
drying process is a complex process of heat and mass transfer which includes the heat exchange between the wood surface and the medium, thermal conductivity and moisture conduction inside the material, evaporation of moisture on its surface. To study the heat and mass transfer it is necessary to know the distribution of moisture in the cross section of material. Basically, the nature of moisture distribution inside the material is considered for the research in the form of a parabolic or cosine dependence. The cosine dependence is described by the drying rate law in the form of moisture balance. Moisture evaporates from the material surface. The resulting physical and mathematical model is the starting position for the methodology of the kinetics experimental studies of drying process. The moisture content of the central and surface layers of wood, change in the average moisture content at the drying process, linear dimensions of blanks, operational parameters of the drying process (the environmental temperature and the equilibrium moisture content of wood) are determined experimentally. The paper presents formulas, determining the coefficients of drying, moisture conduction, moisture-yielding ability, mass exchange Nusselt and Fourier numbers.
According to the experimental data the drying curves reflecting the change in the moisture content during the drying process and the drying rate curves, which help to determine the kinetic characteristics of the process, should be constructed. The drying rate during the test is reduced by more than six times. The obtained values of drying and moisture coefficients can be used in the theoretical equations to determine the duration of the drying process. Kinetics general characteristics of drying process are dimensionless Nusselt and Fourier


P.V. Biley, Doctor of Engineering Sciences, Professor R.A. Rokun', Postgraduate Student


National Institute of Forestry of Ukraine, General Chuprynka str., 103, Lviv, 79057,
Ukraine; e-mail:,


wood, moisture content, drying coefficient, moisture conduction, moisture- yielding ability, criteria, kinetics.


1. Biley P.V. Sushka drevesiny tverdykh listvennykh porod [Wood Drying of Solid Hardwood]. Moscow, 1992. 224 p.
2. Kays W.M. Convective Heat and Mass Transfer. New York, 1966.
3. Lykov A.V., Mikhaylov Yu.A. Teoriya teplo- i massoperenosa [The Theory of Heat and Mass Transfer]. Leningrad, 1963. 535 p.
4. Lykov A.V. Teplomassoobmen [Heat and Mass Transfer]. Moscow, 1978. 480 p.
5. Alyushin S.Zh., Berezovskiy V.Yu., Biley P.V., Buryshev S.A., Prikhod'ko N.V., Strelkov S.A. Sushka drevesiny [Drying of Wood]. Kiev, 2004. 440 p.
6. Shubin G.S. Teoriya teplovoy obrabotki i raschet protsessov sushki drevesiny [Theory of Heat Treatment and Calculation Processes of Wood Drying]. Moscow, 1973. 248 p.
7. Chudinov B.S. Voda v drevesine [The Water in the Wood]. Novosibirsk, 1984. 270 p.
8. Bіley P.V., Petrishak І.V., Sokolovs'kiy І.A., Soroka L.Ya. Teplomassoobmіnnі protsesi derevoobrobki derevini (Pіdruchnik) [Heat and Mass Transfer Processes of Wood Processing]. Lvіv, 2013. 376 p.
9. Brunner-Hildebrand. Die Schnittholztrocknung. Hannover, 1987. 322 p.
Received on February 08, 2015

Kinetics of Drying of Wood Profile Blanks


Make a Submission


Lesnoy Zhurnal (Russian Forestry Journal) was awarded the "Seal of Recognition for Active Data Provider of the Year 2024"