The 2D Eulerian Approach of Entrained Flow and Temperature in a Biomass Stratified Downdraft Gasifier

Abstract

This paper describes a “1-D+2-D” numerical model used to simulate the gasification of pine wood pellets in a stratified downdraft gasifier whereby Eulerian conservation equations are solved for particle and gas phase components, velocities and specific enthalpies. The model takes into account the biomass particle process such as heating up, drying, primary pyrolysis of biomass, secondary pyrolysis of tar, homogeneous reactions and heterogeneous combustion/ gasification reactions and particle size change. This CFD model can be used to predict temperature profiles, gas composition, producer gas lower heating value and carbon conversion efficiency and the reactor performance when operating parameters and feed properties are changed. The standard κ-ε and RNG κ-ε models were used to simulate the turbulent flow conditions.