Search Results

A novel Fast Response Chemiluminescence Detector and a Fast Flame Ionization detector have been used to examine the instantaneous NO and unburnt hydrocarbon concentration in the cylinder and exhaust port of a DI Diesel engine. The in-cylinder results indicate very high levels of NO in the premixed phase of combustion, followed by generally lower levels during the diffusion burning phase. Hydrocarbon signals also indicate significant detail. The in-cylinder uHC signal is consistent with the probe location being between two of the fuel sprays. Both in-cylinder and exhaust results indicate rather high cyclic variability in the NO levels at steady conditions. Variations in the timing and structure of the exhaust uHC signal during the valve open period with load may give insight into the fuel spray/air motion.

A new Diesel Particulate Generator (DPG) has been developed and commercialized for the automated testing of full-size, light duty Diesel Particulate Filters (DPFs). The system was optimized for filter development testing with a wide parameter range of relevant functional tests, and quality assurance testing where repeatability and rapid testing is important. A carefully designed Diesel-fuelled burner is combined with blowers to produce flows, temperatures and particulate matter (PM) that are representative of Diesel engines. The burner operates with continuous combustion of a Diesel fuel spray, with three-stage introduction of controlled airflows. Variation of these flows allows control of particulate generation independently of total gas flow and temperature (over a temperature and flow range). The system can generate stable PM at more than 20 g/h, or operate without PM formation so permitting preheating of a test filter.