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煤气化模拟(文献)

Introduction

    This study provides a description of CPFD (Snider 2009) modeling for fluid-solid flow with solids and gas chemistry. The example chemistry is pyrolysis of solids and homogenous gas chemistry in a high temperature thermal environment. The example problem, illustrating the computational method, is a large three dimensional gasifier.
    For the most part, mathematical models of separated particulate multiphase flow have used either a continuum approach for both phases (Gidaspow, 1986, Batchelor, 1988, Jackson, 2000) or a continuum approach for the fluid and a Lagrangian computational-particle model for particle phase (Cundall and Strack, 1979, Amsden, et al,, 1989, Snider 2001, Godlieb, et al, 2007). The two-fluid continuum approach averages both fluids and solids by a statistical procedure (typically ensembleaveraging) and treats the solids phase as a pseudo continuum. The averaging procedure leads to many
unclosed terms which must be modeled (Jackson, 2000), and much progress has been made in the modeling of such terms as the particle-particle-stresses and particle viscous-stresses in dense particle flows using spatial gradients of average particle properties (Batchelor, 1988, Gidaspow, 1994). The two-fluid continuum approach has trouble modeling flows with a distribution of particle types and sizes because separate continuity and momentum equations must be solved for each size and type (Gidaspow, 1994, Risk, 1993). Size variation and different solid materials affect the bed dynamics with possible solids segregation, and the solid size distribution can produce or suppress gas flow patterns such as gas streaming (Karri, et al. 2004). In thermal, reacting flows, the solid not only changes size from pyrolysis, but the rate of reactions and temperatures can depend on solids surface area, type of solid material and discrete solids temperature.
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2011-6-7 17:48:00 efluid说

可以下载了

2011-5-12 10:07:00 石靖宇说

怎么下载不了啊


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