Coal layer under microwave heating: analytical study under mixed boundary conditions I and II of the genus

Abstract

The relevance of the work is due to the prospect of the use of microwave radiation in the energy technologies of fuel use at the stages of preparation of solid fuels for coal-fired incineration, including drying and heat treatment. A few well-known results of laboratory experiments indicate structural effects, resulting in increased reactivity and reduction of unburnt fuel. Objective: to obtain an analytical expression for the temperature field in the coal array required for parametric analysis of technological conditions of microwave exposure. Methods: construction of analytically rigorous heat transfer problems, the solution of which is usually possible only in conditions of significant simplifications. If adopted by the constancy of the electrical and technological properties of coal physical picture of the process is determined by the incident on the coal layer of a plane electromagnetic wave that generates internal heat source of Buger law. The energy equation in the form of Fourier is solved independently of Maxwell equations. In this formulation the solution of allocated tasks is carried out by the method of integral transformation of Laplace. Results. The derived analytical solutions of temperature fields are received with mixed boundary conditions with fairly arbitrary changes in time and temperature of a surface flux density of fire on the border. For some special cases on this basis can be obtained an extensive series of simplified solutions available for parametric analysis of the rationale of optimal control parameters of the technology demanded by the engineering practice in project development and operation of microwave systems for processing of solid fuels in the energy sector.

Keywords

• coal
• microwave energy
• Maxwell equations
• Fourier heat equation
• Buger law
• mixed boundary conditions