An experimental study to analyze influence of porous media combustor on performance and emission characteristics of a DI diesel engine

Abstract

In this work, the performance analysis of a diesel engine fitted with a porous medium (PM) combustor is investigated. Three different sizes of Silicon carbide (SiC) porous medium such as 10, 20, and 30 Pores Per Inch (PPI) were evaluated. The porous medium was installed into the piston bowl to study the variation in performance, combustion and emission characteristics. Results show that heat recuperation capability of the porous medium leads to an increase in the air/fuel mixture homogenization and helps in reducing Oxides of Nitrogen (NOx). It was noted that at full load with 10 PPI PM, NOx emission significantly reduced by 37% when compared to the base findings. The increasing trend of unburned hydrocarbons, carbon monoxide, and smoke emissions reveals that there is a reduction in combustion pressure, temperature and lack of availability of oxygen inside the PM. Marginal drop-in thermal efficiency is also observed with all PM. Amongst three different PPI porous mediums, 10 PPI SiC ceramic porous medium combustor was found to be superior from the point of performance, combustion and emission characteristics.