Synergetic influence of urea addition on performance and emissions of hydrogen–diesel dual fuel engine

An important measure that shows the total amount of greenhouse gases released into the environment is the carbon footprint by using fossil fuels. Sustainable alternatives are seen as an effective step in both preventing the depletion of fossil fuels and combating climate change. To overcome these negative consequences, the use of area with hydrogen is becoming increasingly popular among fuel researchers. However, the application of hydrogen as a fuel can potentially increase NOx emissions. For this reason, water–urea solution of 5% by volume was added to diesel–hydrogen dual fuel engine. Subsequently, the intake manifold was supplied with 1 LPM of hydrogen. Different engine loads were evaluated, while diesel engine was operated at 1500 rpm rated speed. As a result, the addition of 5% urea and 1 LPM of hydrogen to diesel led to a decrease in BSFC by 23% and an improvement in thermal efficiency by 25% compared to diesel fuel. Blend of diesel oil with urea and hydrogen decreased EGT by 2% lower than diesel oil. NOx, CO, HC and CO₂ concentrations were decreased by 5, 61, 13 and 53%, respectively, when diesel was mixed with urea and hydrogen about diesel oil. Engine performance may be improved, and exhaust pollutants can be reduced by utilizing diesel oil combined with hydrogen and urea as an alternative fuel.