NUMERICAL INVESTIGATION OF WATER ADDITION INTO INTAKE AIR IN MODERN AUTOMOBILES DIESEL ENGINES

In the present study, the effects of water addition into intake air (WAIA) on combustion, engine performance, and NO emission in diesel engines were investigated numerically. Here, Ferguson's thermodynamic-based zero-dimensional single-zone cycle model was used and improved with some new approaches for neat diesel fuel (NDF) and WAIA. After controlling the model's accuracy for NDF and WAIA, the effects of WAIA were first investigated in the Renault K9K diesel engine. For (5 and 7.5)% water ratios (WRs), effective power decreased by 4.26% and 7.37%, brake specific fuel consumption (BSFC) increased by 6.95% and 10.56%, and NO emission reduced by 12.43% and 16.39%, respectively. In the second application, the effects of (3, 6, and 9)% WRs on combustion, engine performance, and NO emission in the Renault M9R type diesel engine were investigated at 4000 rpm by using this developed model. For (3, 6, and 9)% WRs, BSFC increased by 0.97%, 3.39%, and 8.25%, and NO emission decreased by 10.31%, 17.66%, and 34.20%, respectively. For (3 and 6)% WRs effective power increased, and NO emission decreased significantly without considerable deterioration in the BSFC at 4000 rpm. Cylinder pressure values and heat release rate increased for (3 and 6)% WRs and decreased for 9% WR.