Experimental Research on Performance Development of Direct Injection Hydrogen Internal Combustion Engine with High Injection Pressure

As a carbon-free power with excellent performance, the direct injection (DI) hydrogen-fueled internal combustion engine (H2-ICE) has the potential to contribute to carbon dioxide (CO2)-neutral on-road transport solutions. Aiming at high thermal efficiency, the influences of key factors on thermal efficiency over wide operating conditions of a turbocharging DI H2-ICE were investigated under the lean-burn strategy. And the nitrogen oxides (NOx) emission characteristics region was clarified in the high efficiency. The results confirm the optimal ignition strategy with the CA50 of 8–9 crank angle degrees after top dead center (°CA ATDC). The late-injection strategy manifests a significant advantage in brake thermal efficiency (BTE) compared with the early-injection strategy, and this advantage can be amplified by the increased load or injection pressure. The effects of injection (EOIs) pressure on BTE exhibit different laws at different EOIs. Under the early-injection strategy, the lower injection pressure improves BTE due to a more sufficient mixing. While under the late-injection strategy with strong mixture stratification, the high injection pressure conditions exhibit a higher BTE due to reduced compression work. In terms of air-fuel ratio, the BTE is improved monotonically with increased λ at low and medium loads. But there is an optimal λ value limited by the oxygen concentration at a high load. The late-injection strategies with high BTE perform a high level of NOx emissions, which confirms the strong trade-off relationship between the thermal efficiency and NOx emissions of H2-ICEs. A moderate late-injection strategy with an EOI of about 40°CA BTDC can significantly reduce the NOx emissions with a slight loss in BTE. The injection pressure shows different effects on NOx emissions in different EOI ranges, depending on the mixture distribution. In addition, ultra-lean burn and lower intake temperature are effective means to reduce NOx emissions without losing thermal efficiency.

[1]  G. Tian,et al.  Review of the backfire occurrences and control strategies for port hydrogen injection internal combustion engines , 2022, Fuel.

[2]  Y. Takagi,et al.  Effect of supercharging on improving thermal efficiency and modifying combustion characteristics in lean-burn direct-injection near-zero-emission hydrogen engines , 2021, International Journal of Hydrogen Energy.

[3]  Dimitri Seboldt,et al.  Hydrogen Engines for Future Passenger Cars and Light Commercial Vehicles , 2021, MTZ worldwide.

[4]  Wenzhi Gao,et al.  Effects study of injection strategies on hydrogen-air formation and performance of hydrogen direct injection internal combustion engine , 2019, International Journal of Hydrogen Energy.

[5]  Yasumasa Suzuki,et al.  Development of a large-sized direct injection hydrogen engine for a stationary power generator , 2019, International Journal of Hydrogen Energy.

[6]  Y. Takagi,et al.  Near-zero emissions with high thermal efficiency realized by optimizing jet plume location relative to combustion chamber wall, jet geometry and injection timing in a direct-injection hydrogen engine , 2019, International Journal of Hydrogen Energy.

[7]  K. Yamane.  Hydrogen Fueled ICE, Successfully Overcoming Challenges through High Pressure Direct Injection Technologies: 40 Years of Japanese Hydrogen ICE Research and Development , 2018 .

[8]  E. Tomita,et al.  Improvement of thermal efficiency and reduction of NOx emissions by burning a controlled jet plume in high-pressure direct-injection hydrogen engines , 2017 .

[9]  Taku Tsujimura,et al.  A review of hydrogen as a compression ignition engine fuel , 2017 .

[10]  L. Das,et al.  Development of hydrogen fuelled transport engine and field tests on vehicles , 2017 .

[11]  Md. Rafiqul Islam,et al.  An overview of hydrogen as a vehicle fuel , 2012 .

[12]  Thomas Wallner,et al.  A Hydrogen Direct Injection Engine Concept that Exceeds U.S. DOE Light-Duty Efficiency Targets , 2012 .

[13]  Thomas Wallner,et al.  Influence of Injection Strategy in a High-Efficiency Hydrogen Direct Injection Engine , 2011 .

[14]  T. Wallner.  Efficiency and Emissions Potential of Hydrogen Internal Combustion Engine Vehicles , 2011 .

[15]  Shiro Tanno,et al.  High-Efficiency and Low-NOx Hydrogen Combustion by High Pressure Direct Injection , 2010 .

[16]  Thomas Wallner,et al.  Efficiency Improved Combustion System for Hydrogen Direct Injection Operation , 2010 .

[17]  F. Salimi,et al.  Role of mixture richness, spark and valve timing in hydrogen-fuelled engine performance and emission , 2009 .

[18]  Thomas Wallner,et al.  Operating strategy for a hydrogen engine for improved drive-cycle efficiency and emissions behavior , 2009 .

[19]  Thomas Wallner,et al.  Study of Basic Injection Configurations using a Direct-Injection Hydrogen Research Engine , 2009 .

[20]  Roger Sierens,et al.  Efficiency comparison between hydrogen and gasoline, on a bi-fuel hydrogen/gasoline engine , 2009 .

[21]  Toshio Shudo,et al.  Improving thermal efficiency by reducing cooling losses in hydrogen combustion engines , 2007 .

[22]  R. Steeper,et al.  The hydrogen-fueled internal combustion engine : a technical review. , 2006 .

[23]  Hermann Rottengruber,et al.  Direct-Injection Hydrogen SI-Engine - Operation Strategy and Power Density Potentials , 2004 .

[24]  R. Freymann,et al.  The Potential of Hydrogen Internal Combustion Engines in a Future Mobility Scenario , 2003 .

[25]  Thomas Aicher,et al.  Renewable Hydrogen Technologies. Production, Purification, Storage, Applications, and Safety. Edited by Luis M. Gandía, Gurutze Arzamendi, and Pedro M. Diéguez , 2015 .

[26]  S. Verhelst,et al.  Hydrogen-fueled internal combustion engines , 2014 .

[27]  H. S. Homan,et al.  The effect of fuel injection on NOx emissions and undesirable combustion for hydrogen-fuelled piston engines , 1983 .