Simulation Analysis of Temperature Field of Step Heating Furnace

Abstract In this study, a step-heating furnace was selected as the subject of investigation. Computational fluid dynamics (CFD) simulations were conducted using Fluent software to develop mathematical models for gas flow, combustion, and slab heating processes within the furnace. The k-ε turbulence model was used to simulate the gas flow, while an unmixed combustion model was utilized to represent the combustion process. For radiation heat transfer, the DO model was employed. The impact of varying oxygen volume fractions (20%,25%,30% and 35%) in the combustion gases and fuel on the furnace temperature and the heating of the slabs was analysed through these models. The simulation outcomes indicated that an increase in oxygen concentration led to a gradual rise in flue gas temperatures within the combustion zone, along with a more even temperature distribution throughout the furnace. Specifically, when the oxygen volume fraction was increased from 20% to 35%, the maximum furnace temperature rose by 213 K. This elevation in temperature accelerated the heating rate of the slabs, thereby enhancing the efficiency of the heating process; the mean discharge temperature of the slabs was observed to be 115K higher.