Coupling a CFD code with a solid phase combustion model

Combustion is an important technology widely applied for conversion of coal and biomass. Large scale development and optimization require mathematical modeling which, allowing quantitative representation of various phenomena, is a powerful tool for process design, prediction of combustor performances, understanding of pollutants evolution, analysis of process transients and examination of strategies for effective control. An unreacted-core-shrinking model is used to describe drying, pyrolysis, gasification and combustion of single thick wood particles under conditions representative of packed bed reactors. A parametric analysis indicates that simulation results are strongly affected by the dynamics of the gas phase. Hence, the solid phase combustion model has been extended to include a description of the multi-dimensional gas phase processes in accordance with the assumptions usually made in commercial CFD codes.