Thursday, March 3, 2011
Performance and emission characteristics of a turbocharged spark-ignition hydrogen-enriched compressed natural gas engine under wide open throttle operating conditions
This article discusses the effects of hydrogen-enriched compressed natural gas on engines performance. The new auto industry has shifted to use these kids of fuel because it can be obtained from electrolysis of water and the electricity used can be generated by solar energy, which means hydrogen is a kind of real renewable energy. Although, it is a new and reliable kind of energy, it has issues in production, storage and distribution if hydrogen is used as energy. An online mixing system was developed in order to mix together desired amount of hydrogen with natural gas entering the engine. The tank was divided into two rooms with a damping line. The flow rate of CNG and H2 were measured by a Micro Motion flow meter that uses the principle of Coriolis force for a direct measure of mass flow. Moreover, hydrogen-enriched compressed natural gas was tested on a six cylinder engine. The record length of pressure data in this study is 250 K (about 347 cycles) which is enough for CCV analysis. The test was perform under different WOT operating circumstances including different spark timings, excess air ratio in order to evaluate performance and emission characteristics with the various hydrogen volumetric ratios 0%, 30%, 55% HCNG fuels. In order to avoid knocking and to avoid exceeding the limit of maximum cylinder pressure, the experimental strategy was to optimize the spark timing at lean burn conditions. Hydrogen-Enriched Compressed Natural Gas is much more efficient and cheaper than other forms of gas. It is also of less pollution to the environment. We should start using it from now on to be green people in the environment.