STUDY OF THE PARAMETERS OF THE INITIAL WOOD HEATING TECHNOLOGY IN AN UNSATURATED ENVIRONMENT

UDC 674.04.047.3

  • Rudak Oksana Gennadievna − Master of Engineering, Senior Lecturer, the Department of Technology and Design of Wooden Articles. Belarusian State Technological University (13a, Sverdlova str., Minsk, 220006, Republic of Belarus). E-mail: oksrudak@mail.ru

DOI: https://doi.org/10.52065/2519-402X-2021-246-34-268–276

Key words: heating, technology, duration, temperature difference, degree of saturation.

For citation: Rudak О. G. Study of the parameters of the initial wood heating technology in an unsaturated environment. Proceedings of BSTU, issue 1, Forestry. Nature management. Processing of Renewable Resources, 2021, no. 2 (246), pp. 268–276 (In Russian).DOI: https://doi.org/10.52065/2519-402X-2021-246-34-268–276.

Abstract

The article presents the results of a study of the mechanisms of the initial heating of wood in an unsaturated environment. The main parameters of the technological process of heating sawn timber, which affect the duration of heating and the value of internal stresses (qualitative assessment), have been established. The graphical dependences of the temperature and humidity changes of the surface and inner layers of the samples in time were obtained, which characterize the kinetics of the initial heating of wood. To plan the experiment to determine the duration of the initial warm-up operation, the B-plan of the second order was used. Two-dimensional surfaces of the response function are constructed, presented in the form of a quadratic three-factor regression model. The results of an analytical calculation of the value of internal stresses arising on the surface of wood during heating in an unsaturated environment are presented. The analysis of the influence of technological factors, such as the temperature and degree of saturation of the processing environment, the initial temperature and moisture content of the wood, the thickness of lumber, on the basic laws of wood heating is carried out. Based on the research results, recommendations were developed for the technology of the initial heating of wood in an unsaturated environment. This work draws attention to the fact that with an increased degree of saturation and a temperature of the processing medium above 50°C, the microstructural elements of wood acquire elasticity and plasticity, which, in turn, contributes to the opening of pores, and, accordingly, prepares the moisture-conducting system of wood for subsequent drying.

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22.03.2021