Turbulence Modelling on Fluidized Bed Gasification

Abstract

Energy generation from carbon based solid materials, such as coal by a gasification process increasingly gets an essential research subject, as current energy sources getting to a close. Waste material management is also great significance to dispose them sustainably and efficiently from environment. There is, therefore, the need of advanced modelling approach to maximize the efficiency of coal-derived synthesis gas, and to optimize process parameters for designing a new gasifier. Hence, two-dimensional (2-D) gasification system was initially simulated by using commercial code ANSYS FLUENT. Devolatilization and char combustion chemical reactions of the process were modelled by User Defined Functions (UDF) to simulate their chemical kinetics more accurately. After mesh independency study and model validation performed, RANS based turbulence models were examined to find out best turbulence modelling approach. Performance evaluation was done and energy efficiency of the gasification system were also calculated.

Keywords

• Solid waste material,Waste management,Gasification,Combustion,Turbulence,Modeling,CFD

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