A CFD-based Combustion Model of an Entrained Flow Biomass Gasifier

Department of Chemical Engineering, University of Sydney, Sydney, NSW 2006, Australia
Applied Mathematical Modelling (Impact Factor: 2.25). 03/2000; 24(3):165-182. DOI: 10.1016/S0307-904X(99)00025-6


The Silences of the Archives, the Reknown of the Story.
The Martin Guerre affair has been told many times since Jean de Coras and Guillaume Lesueur published their stories in 1561. It is in many ways a perfect intrigue with uncanny resemblance, persuasive deception and a surprizing end when the two Martin stood face to face, memory to memory, before captivated judges and a guilty feeling Bertrande de Rols. The historian wanted to go beyond the known story in order to discover the world of the heroes. This research led to disappointments and surprizes as documents were discovered concerning the environment of Artigat’s inhabitants and bearing directly on the main characters thanks to notarial contracts. Along the way, study of the works of Coras and Lesueur took a new direction. Coming back to the affair a quarter century later did not result in finding new documents (some are perhaps still buried in Spanish archives), but by going back over her tracks, the historian could only be struck by the silences of the archives that refuse to reveal their secrets and, at the same time, by the possible openings they suggest, by the intuition that almost invisible threads link here and there characters and events.

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Available from: David Frederick Fletcher, Jun 24, 2014
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    • "Eulerian–Lagrangian strategies provide an alternative framework that typically relies on simpler closures, where individual particle trajectories are solved using Newton's laws of motion, and models are required for interphase exchange and particle collisions . Because of the added computational expense of tracking individual particles, Eulerian–Lagrangian methods coupled with a chemistry model have only recently been applied in three dimensions (Bruchmüller et al., 2012; Li et al., 2013), but are typically limited to two-dimensional flows with a relatively small number of particles (e.g., Fletcher et al., 2000; Papadikis et al., 2009; Oevermann et al., 2009; Rabinovich et al., 2010; Wu et al., 2010). "
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    Full-text · Article · Jan 2015 · Chemical Engineering Science
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    • "If coupled with chemical reactions computation is more and more complicated and expensive (Wang et al., 2009). Most reported multiphase CFD models in literature are either for biomass gasification in entrained flow gasifiers or for fluidized bed gasification using EEM (Xue et al., 2011; Fletcher et al., 2000; Nguyena et al., 2012). Recently, Papadikis et al. (2008, 2009) used two-and three-dimensional Eulerian framework combined with only one discrete particle for simulating fast pyrolysis of biomass in fluidized bed gasifiers. "
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    ABSTRACT: A comprehensive three-dimensional numerical model is developed to simulate forestry residues gasification in a fluidized bed reactor using Eulerian-Lagrangian approach. The complex granular flow behaviors and chemical reaction characteristics are addressed simultaneously. The model uses an Eulerian method for fluid phase and a discrete particle method for solid phase, which takes particle contact force into account. Heterogeneous and homogenous reaction rates are solved on the Eulerian grid. The numerical model is employed to study the gasification performance in a lab-scale pine gasifier. A series of simulations have been performed with some critical parameters including temperature, equivalence ratio and steam to biomass ratio. The model predicts product gas composition and carbon conversion efficiency in good agreement with experimental data. The formation and development of flow regimes, profiles of particle species, and distributions of gas compositions inside the reactor are also discussed.
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    • "(4)), they effectively provide the thermal energy that is needed for the other endothermic reactions in the gasifier. The reactions take place as follows [12] [13] [14] [15] [16]: "
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