Numerical assessment of interchangeability potential for syngas-fueled rotary engine

Abstract

The syngas-fueled rotary engine can be considered as a promising solution for small–scale decentralized power generation due to high specific power, engine simplicity, smoothness and a low tendency for abnormal combustion. Since the decisive feature of syngas refers to feedstock flexibility, in this study we consider syngas with various compositions, produced from biomass, coal and natural gas, as a primary fuel for rotary engines. It was shown that rotary engine performance, efficiency and emission are mostly affected by the balance between combustion promoters and diluents in the air-syngas mixture. Particularly, high hydrogen concentration and lower inert content result in maximum power, heat release and thermal efficiency for stoichiometric and lean conditions. For the rotary engine with a homogeneous charge of the fuel, the combustion process is characterized by the weak influence of turbulence, while the laminar flame speed is an influential parameter in combustion behavior. The high magnitude of specific fuel consumption makes it difficult for engine operation at lean conditions. Although, the lean mixture cannot provide enough high flame temperature for NOx formation. The CO2 emission is affected by the hydrogen to carbon ratio. The opposite trend is observed between NOx and CO emission pathways due to oxygen availability. The power generation system based on the syngas-fueled rotary engine with syngas produced by not only well-known technology such as gasification or steam reforming but novel concepts (non-catalytic partial oxidation) can provide sustainability to the energy sector and reduce consumption of fossil fuels..