This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
A Study on the Mechanism of Backfire in External Mixture Formation Hydrogen Engines -About Backfire Occurred by Cause of the Spark Plug-
Annotation ability available
Sector:
Language:
English
Abstract
It is a well-known fact that the exhaust emission characteristics of hydrogen fueled engines are extremely good. The external mixture formation - a hydrogen fuel supply method - has the merit of practically zero NOx emission level in the lean mixture range with the excess air ratio λ set at 2.0 or greater as well as the merits of simple mechanism and easy operation. However, the practical use of such engines has been impeded partly due to the occurrence of backfire where the excess air ratio λ is 2 to 3. In order to allow the practical use of the hydrogen fueled engines with external mixture formation, it is vital to determine the causes of backfire and to establish proper countermeasures.
It is found through a recent study conducted on the mechanism of backfire that the abnormal electric discharge in the intake stroke is one of the causes of backfire. It is also found that the abnormal electric discharge is caused by the high energy retained in the ignition system due to low ion current flows resulting from lower ion concentrations in hydrogen flames relative to gasoline flames. The engine performance was improved dramatically by modifying the ignition system to prevent residual energy. However, backfire would still occur when the excess air ratio λ was 1.6 or so. The backfire threshold was improved by cooling the spark plug electrode with water to lower the temperature.
Recommended Content
Technical Paper | Study on Mechanism of Backfire in Hydrogen Engines |
Technical Paper | Effect of Injection Timing on Backfire of Port Injection Hydrogen Engine |
Technical Paper | STUDY ON THE PROCESS OF BACKFIRING |
Authors
Topic
Citation
Kondo, T., Iio, S., and Hiruma, M., "A Study on the Mechanism of Backfire in External Mixture Formation Hydrogen Engines -About Backfire Occurred by Cause of the Spark Plug-," SAE Technical Paper 971704, 1997, https://doi.org/10.4271/971704.Also In
References
- King R.O. “The Hydrogen Engine and the Nuclear Theory of Ignition” Can.J.Res.F. 26 264 1948
- Furuhama S. “Combustion Improvement in a Hydrogen Fueled Engine” Int.J.Hydrogen Energy 2 3 329 1977
- Koyanagi K. et al. “Study on Occurring Mechanism of Backfire in Hydrogen Engines” JSME, No.940-30 III 341 1994
- Fueno aT. “Chemi-ionization” Chemistry and Industry 19 6 132 1966
- Terada K. Suzuki S. “Measuring Ignition and Combustion by Detecting Ionization Current” Internal Combustion Engine 17 212 1978