Effects of steam addition and/or injection on the combustion characteristics: A review

Abstract

Due to increasing global energy demand and the fact that a major source of the required energy is generated from fossil fuels, the combustion process has turned into a topic of interest in converting fossil fuels to energy. An ideal combustion system is one that can combine high engine efficiency with low fuel consumption and low emissions. Increasing humidity is a technique used by researchers for influencing the combustion process. The present study aims to review previously conducted researches in this regard. Based on viewpoints of these researches, the reviewed studies were categorized into four groups: (1) the case studies used; (2) the methodology applied; (3) the design guidelines considered; and (4) the performance parameters studied. It can be concluded from the reviewed articles that nitrogen oxide (NOx) reduction is the most significant advantage of increasing humidity in the combustion process, and has led to the widespread use of this method. The other studied emissions either remained constant or their respective increases were negligible.