Direct Injection of Natural Gas at up to 600 Bar in a Pilot-Ignited Heavy-Duty Engine

Event
SAE 2015 World Congress & Exhibition
Authors Abstract
Content
Retaining the diesel combustion process but burning primarily natural gas offers diesel-like efficiencies from a natural-gas fuelled heavy-duty engine. This combustion event is limited by the injection pressure of the fuel, as this dictates the rate of mixing and hence of combustion. Typical late-cycle direct injection applications are limited to approximately 300 bar fuel pressure. The current work reports on tests for the first time at natural gas injection pressures up to 600 bar. The results show that significant efficiency and particulate matter reductions can be achieved at high loads, especially at higher speeds where the combustion is injection rate limited at conventional pressures. Increases in combustion noise and harshness are a drawback of higher pressures, but these can be mitigated by reducing the diameter of the nozzle gas holes to control the fuel injection rate. Higher pressures lead to faster combustion, which allows earlier combustion phasing without exceeding peak cylinder pressures, improving efficiency. Steady-state cycle-composite results show that efficiency benefits on the order of 3% and PM reductions of 40-60% can be achieved through increased gas rail pressures.
Meta TagsDetails
DOI
https://doi.org/10.4271/2015-01-0865
Pages
16
Citation
McTaggart-Cowan, G., Mann, K., Huang, J., Singh, A. et al., "Direct Injection of Natural Gas at up to 600 Bar in a Pilot-Ignited Heavy-Duty Engine," SAE Int. J. Engines 8(3):981-996, 2015, https://doi.org/10.4271/2015-01-0865.
Additional Details
Publisher
Published
Apr 14, 2015
Product Code
2015-01-0865
Content Type
Journal Article
Language
English