Direct Injection of Natural Gas in a Heavy-Duty Diesel Engine
2002-01-1630
05/06/2002
- Event
- Content
- The high-pressure direct injection (HPDI) of natural gas permits diesel engines to retain their performance and high fuel economy while reducing regulated emissions. In the work presented in this paper, a pilot diesel fuel ignites directly injected natural gas, and both fuels are injected through a single injector. Recently the HPDI engine achieved a combined NOx+nmHC emissions of 2.38 g/bhp-hr during official certification tests performed under the US EPA specified FTP cycle for heavy-duty diesel engines. NOx, nmHC and PM emissions were reduced by 45%, 85% and 71%, respectively, compared to the 1998 EPA emissions requirement. These results are consistent with previously reported results on a two-stroke engine. The present study clearly demonstrates that a combination of gas injection timing and pressure can significantly reduce NOx emissions while retaining the overall thermal efficiency.
- Pages
- 12
- Citation
- Harrington, J., Munshi, S., Nedelcu, C., Ouellette, P. et al., "Direct Injection of Natural Gas in a Heavy-Duty Diesel Engine," SAE Technical Paper 2002-01-1630, 2002, https://doi.org/10.4271/2002-01-1630.