Experimental Investigation of the Effects of Water Injection into Inlet Air on Engine Performance and Exhaust Emissions in a DI Diesel Engine
Zehra Sahin Mustafa Tuti Orhan Durgun
AbstractIn the present study, the effects of water injection into intake air on the performance and exhaust emissions were experimentally investigated in a Renault K9K 700 type turbocharged common-rail DI automotive diesel engine. Experiments were performed under seven different loads such as (150, 140, 130, 120, 110, 100 and 90) Nm at 2000 rpm and under six different load such as (115, 100, 86, 72, 57, and 43) Nm at 4000 rpm for various water ratios (WRs). Here, water was injected into intake air by using an adapted carburetor, which main nozzle section is adjustable to give approximately 2 %, 4 %, 6 %, 8 %, 10 %, 12 % and 14 % (by vol.) water ratios. The test results showed that effective power values for selected WRs under 150 Nm at 2000 rpm increases. However, under other loads it takes nearly equal values to neat diesel fuel (NDF) until 6 % WR and after this ratio it starts to decreases. Effective power decreases generally at 4000 rpm. Break specific fuel consumption (bsfc) increases for light WRs (2% and 4%) and high WRs (10%, 12% and 14%) but it generally decreases for 6% and 8% WRs at 2000 rpm. bsfc generally increases for all of the selected operating conditions at 4000 rpm. NOx emissions decrease considerably with increasing WRs at 2000 rpm at 4000 rpm. HC decreases at 2000 rpm. However, opacity decreases until 6 % WR and after this ratio it starts to increases at this engine speed. HC decreases until 8 % WR and after this ratio it increases at 4000 rpm. Opacity is nearly equal to NDF until 6 % WR but after this ratio it increases at this engine speed