Theoretical and experimental investigation of steam injected diesel engine with EGR

•EGR is applied to steam injected DI diesel engine to reduce NOx emissions.•This method reduces NO emissions up to 46% comparing steam injected diesel engine.•Combustion model was used to estimate emission and performance parameters.•Combustion model has quite well with the experimental results.

Steam injection technique newly proposed with EGR (exhaust gas recirculation) is applied into a direct injection diesel engine to decrease NOx emissions for the objective of reaching the new emission regulations. Experimental and combustion model as a theoretical methodology has been done. Steam injected diesel engine with EGR has been performed using a combustion model for 20% steam (S20) and 10% EGR (E10) ratios of fuel mass injected per cycle at full-load conditions. The results have been compared with S20 in terms of performance and NO, CO, CO2, and HC emissions. In the experimental results, NO emissions decreased up to 48.3% at the condition of S20 + E10 when compared to S20 with the increase of 3.5% in SFC (specific fuel consumption). As a result, when the small deterioration in the SFC is tolerated, the presented study could be used as an essential tool by the real-engine designers.