Theoretical study of wood waste briquetting taking into account nonlinear strengthening of the raw materials
The study is aimed at developing the theoretical description of the process of briquetting wood raw materials. The purpose of this article is to unify the approach to building a model for pressing a wood material as an elastic-viscous-plastic body and consider its hardening in accordance with the power-law dependence of the plasticity limit on density. The study is based on the analysis of the results obtained earlier in the field of mathematical modeling of the pressing of hardening wood materials. The implementation of the proposed dependencies is carried out using the methods of approximate solution of differential equations in the Maple computer mathematics system. The developed unified model makes it possible to predict the stress that occurs in the briquetted wood material and, therefore, to estimate the pressing pressure required to form a briquette with a given strength. An important feature of the proposed model is that the replacement of the equation for the plasticity limit or its parameters does not require a revision of its entire structure. It has been established that the implementation of the numerical solution of the differential equation of the relationship between stress and strain of an elastic-viscous-plastic body with the inclusion of a nonlinear dependence of the ultimate strength in the modern Maple computer mathematics system did not cause computational difficulties. The prospect of further research is to conduct additional experiments in order to clarify the nonlinear dependence of the plasticity limit on density and other physical, mechanical and qualitative parameters of the processed raw materials.