A study on a solution to reduce emissions by using hydrogen as an alternative fuel for a diesel engine integrated exhaust gas recirculation

Abstract

Although diesel engines are the most reliable energy source in the transport industry, increasingly strict emissions targets and the rapid depletion of oil resources have spurred researchers to try. Research to use alternative fuels for diesel. Hydrogen is one of the best alternatives to traditional fuel. Hydrogen has its own benefits and limitations in its use as an alternative fuel in diesel engines. On the other hand, one of the effective methods to improve combustion efficiency on existing engines without changing a lot of engine structure is to add a small amount of hydrogen gas or hydrogen rich gas to the engine. Hydrogen has fast diffusion, flammable and fast burning characteristics, so when it is ignited in a mixture with traditional fossil fuels in engine cylinder, it will increase the burning speed of the fuel mixture and helps fuel burn completely, thereby increasing combustion efficiency and reducing engine emissions. A study on supplying hydrogen or hydrogen-rich gas to diesel engines right on the engine intake through the EGR flue gas recirculation system to improve combustion, improving efficiency and reducing engine emissions will have high scientific and practical significance. In this paper, an experimental study was conducted on four stroke diesel engine driving a generator. The engine is supplied with hydrogen-rich air on the intake charge by integrating an exhaust gas recirculation (EGR) system with a flow of 25 l/min. In this study, the authors focused on the evaluation of specific fuel consumption, thermal efficiency and emission characteristics of engines with different levels of EGR use. Experimental results show that when the rate of using hydrogen increases, the emission level of particles and NOx are significantly reduced.