A Thermo-Mechanical Model for a Counterflow Biomass Gasifier

Abstract:

This article presents a thermo-mechanical approach to investigate heat transfer between solid and fluid phases in a model gasifier. A two-temperature equation approach is applied in addition to a macroscopic model for laminar flow through a porous moving bed. Transport equations are discretized using the control-volume method and the system of algebraic equations is relaxed via the SIMPLE algorithm. The effects on inter-phase heat transfer due to variation of medium permeability, thermal conductivity and thermal capacity are analyzed. Results indicate that for smaller medium permeabilities, as well as for higher solid-to-fluid thermal capacity and thermal conductivity ratios, enhancement of heat transfer between phases is observed.

• Periodical: Defect and Diffusion Forum (Volume 354)
• Pages: 227-235
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.354.227
• Online since: June 2014
• Authors: Marcelo J.S. de Lemos
• Keywords: Counterflow, Heat Transfer, Model Gasifier, Moving Bed, Porous Media

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