A Particle-Resolved CFD Model of the Combustion and Gasification Processes of Coke
Tóm tắt
With the aim of optimizing the processes near the tuyeres of a coke-fired cupola furnace, a mathematical model based on computational fluid dynamics was developed that takes into account the combustion and gasification processes of lump coke at the particle scale. Basic fluid mechanics equations were used for the modeling and were supplemented by additional transport properties. The main task was to define the equations with appropriate constants as well as specific sources and sinks that correspond to individual processes. To assure the accuracy of the calculated physics, the model was developed by simulating each single subprocess separately and comparing the simulation results with either well-known submodels or experimental results. Furthermore, the detailed flow around the particles was enhanced with mass and heat transfer, which requires the dynamic boundary layer to be resolved. Due to the high computational effort, the latter was one of the major challenges of this project. After the initial setup, the model was assessed using the simple geometry of a column of spheres as an example. The computed results showed the expected response to the boundary conditions and good agreement with experimental data from the literature.
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