Speaker
Description
In order to satisfy carbon neutrality in transportation sector, carbon-free gases such as hydrogen and ammonia should be considered as a fuel for an internal combustion engine in the near future. Hydrogen can be a gamechanger of greenhouse gas problem replacing existing fossil fuels. However, due to high reactivity, wide flammability limit and small minimum ignition energy of hydrogen, lots of care should be concentrated on the development of hydrogen engine. In this study, a 2-liter direct injection type hydrogen engine was experimented and its combustion and emission characteristics were assessed. Borgwarner hydrogen injector was adopted and injection pressure of up to 36 bar was used in this evaluation. In order to minimize NOx emission, ultra-lean combustion was intended and no additional aftertreatment device was utilized. Also, to boost intake air and therefore to increase overall power of the engine, turbocharger and supercharger were used solely or together. Exhaust gas recirculation scheme was also tested to further decrease NOx emission. All the data with a direct injection hydrogen engine were compared to those with a port injection hydrogen engine and with a direct injection gasoline engine as well. Overall, a direct injection hydrogen engine could be stably operated in the entire engine speed and load condition. Although there was a pre-ignition or knocking problem at high load condition, frequency of abnormal combustion was not that significant and could be controllable. Less than 15 ppm of NOx was obtained at the major 8 points engine operating conditions showing almost the same power or more power of a gasoline engine. In addition, less than 200 ppm of CO2 emission was witnessed in the tailpipe of a hydrogen engine. In conclusion, hydrogen can be utilized as a fuel for a 2-liter reciprocating engine with direct injection system showing supreme combustion and emission performance. Hydrogen engine is expected to be a promising alternative of conventional internal combustion engine and will play an important role in carbon neutrality in transportation sector.
References
Youngrae Kim, Cheolwoong Park, Junho Oh, Young Choi and Jeongwoo Lee, "EFFECT OF EXCESSIVE AIR RATIO ON HYDROGEN-FUELED SPARK IGNITION ENGINE WITH HIGH COMPRESSION RATIO USING DIRECT INJECTION SYSTEM TOWARD HIGHER BRAKE POWER AND THERMAL EFFICIENCY", IJAT, Vol.24, No.1, pp. 29-89, 2023
| Keywords | Hydrogen, Engine, Direct Injection, Combustion, Emission, Carbon Neutrality |
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