The main objective of this work consists in a computational study on the co- ring of biomass with coal in an industrial-scale furnace used for power generation. Particular attention is be paid to investigating the possible e ect of the biomass/coal ratio on ame shape and wall heat ux distribution. One of the issues in the use of pulverized coal (PC) ring for electricity production is the emission of carbon dioxide, which remains a signi cant environmental problem because of climate e ects. In this regard, the utilization of biomass as a co- red fuel has proved to be a signi cant option for the mitigation of greenhouse gas emissions due to the sustainable nature of biomass. Generally, a small amount of biomass co- ring does not require signi cant modi cations to existing burners and boiler systems using pulverized coal (PC). However, to optimize the working parameters and e ciency of PC boilers and burners it is necessary to calculate the maximum biomass/coal ratio allowing existing burners to be used without signi cant modi cations, which may cause additional costs. Such calculations can be carried out using Computational Fluid Dynamics (CFD) models and software. In this work we carried out 3D CFD-based numerical parametric runs to study the in uence of the biomass-blending ratio on the ame behavior and overall heat transfer balance of the boiler. Two di erent blending ratios (20% and 30% of biomass) were studied. We showed numerically, that increase in biomass/coal blending ratio leads to decrease in the overall heat ux. However, the intensity of this change depends strongly on the coal and biomass composition. Main ndings are illustrated and analyzed. The ANSYS-Fluent 16.2 software was utilized. The so called Euler-Lagrange model in the form of Discrete Particle Model (DPM) coupled with di erent models is going to be utilized in 3D CFD simulations. Turbulent ow, cola/biomass particles oxidation reaction, homogeneous chemistry, particle- ow interaction, radiation will be modeled using following models: 1. Turbulent ow: steady-state RANS k-epsilon RNG. 2. Coal/biomass devolatilization: single rate reaction model with multiple-species volatilize gas composition. 3. Cola/biomass particles oxidation: multiple-surface-reaction model based on Baum and Street submodel. 4. Turbulence-chemistry interaction: Finite-Rate/ Eddy-Dissipation model. 5. Particle- ow interaction: discrete particle model for dilute ows. 6. Radiation: P2 - WSGGM-cell-Based model. Applied to PC combustion a nal overall model described above has been validated against experimental data published in the literature. Very good agreement has been achieved.
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