Multiphysics Simulations of Entrained Flow Gasification. Part II: Constructing and Validating the Overall Model

In this paper, we describe the construction, validation, and application of a multiscale model of entrained flow gasification. Part I of the paper focused on the validation of the turbulence and particle turbulent dispersion submodels. In part II, the impact of suggested improvements in these submodels on the predictions of key output parameters is analyzed through appropriate sensitivity analyses. In addition, adaption of the moving flame front (MFF) model of char consumption to gasification computational fluid dynamics (CFD) and its impact on the overall predictions is presented. The accuracy of the integrated gasifier model is demonstrated by comparing its predictions with experimental data from pilot and research-scale Mitsubishi Heavy Industries (MHI) gasifiers and a laboratory scale gasifier from Brigham Young University (BYU). Finally, a practical limit on mesh refinement for RANS simulations of two-phase reacting flows, governed by solution stability, is discussed.