In the last two decades, the interest in the use of solid biomass as a fuel for power generation, together with the continuous tightening of regulations, has motivated the improvement of accurate design techniques which are required to optimize the combustion process, new technologies, and simultaneously control pollutant emissions to the environment. The present review presents an overview of the existing CFD methodologies to model the entire interaction in a grate-fired boiler. This is an important task that delivers a meaningful and trustworthy conclusion that will benefit the community of researchers and engineers.
To date, several studies have been conducted experimentally and numerically. However, although it is difficult to draw a general conclusion about which strategy or models are the most appropriate to the combustion simulation inside a biomass grate-fired boiler, in general, numerical studies have been contributed to a better understanding of the development of this phenomenon, its analysis, and its optimization. Nonetheless, in the last years, a growing trend for integrated bed models inside the CFD models was observed. This approach has become popular due to the rapid advances in computational power and the requirement to obtain more detailed information on the phenomenon. This work is essential to the next task related to the development of a numerical model of biomass combustion grate-fired boiler. It will contribute to the results of industry-academic collaboration applying scientific research to understand and improve the combustion process inside an industrial boiler.