Characteristics of Unburned Hydrocarbon Emissions in a Low Compression Ratio DI Diesel Engine

2009-01-1526

04/20/2009

Event
SAE World Congress & Exhibition
Authors Abstract
Content
In a DI diesel engine, THC emissions increase significantly with lower compression ratios, a low coolant temperature, or during the transient state. During the transient after a load increase, THC emissions are increased significantly to very high concentrations from just after the start of the load increase until around the 10th cycle, then rapidly decreased until the 20th cycle, before gradually decreasing to a steady state value after 1000 cycles. In the fully-warmed steady state operation with a compression ratio of 16 and diesel fuel, THC is reasonably low, but THC increases with lower coolant temperatures or during the transient period just after increasing the load. This THC increase is due to the formation of over-lean mixture with the longer ignition delay and also due to the fuel adhering to the combustion chamber walls. A low distillation temperature fuel such as normal heptane can eliminate the THC increase. Benzene, 1,3-butadiene, and other unregulated harmful emissions also increase under the high THC conditions.
Meta TagsDetails
DOI
https://doi.org/10.4271/2009-01-1526
Pages
7
Citation
Ogawa, H., Miyamoto, N., Kawabe, T., and Tosaka, S., "Characteristics of Unburned Hydrocarbon Emissions in a Low Compression Ratio DI Diesel Engine," SAE Technical Paper 2009-01-1526, 2009, https://doi.org/10.4271/2009-01-1526.
Additional Details
Publisher
Published
Apr 20, 2009
Product Code
2009-01-1526
Content Type
Technical Paper
Language
English