Browse Publications Technical Papers 2000-01-1945
2000-06-19

Tracer Fuel Injection Studies on Exhaust Port Hydrocarbon Oxidation: Part II 2000-01-1945

Recently, studies were conducted on a single cylinder, four stroke engine to investigate the effect of temperature and local mixedness on exhaust port hydrocarbon oxidation. To examine the effect of temperature, hydrocarbon tracers (propane, propene, 1-butene, n-butane, and n-pentane) were individually injected into the exhaust port just behind the exhaust valve for operating conditions that provided different exhaust port temperatures. For the local mixedness experiments, tracer mixtures (propane + n-butane, 1-butene + n-butane, propene + n-butane) were injected into the exhaust port just behind either a normal exhaust valve or a shrouded exhaust valve. The concentration of tracers and their reaction products were measured using gas chromatography of samples withdrawn from the exhaust stream. The tracer consumption behavior with changing port temperature confirmed that there is a minimum port temperature for hydrocarbon oxidation. This “cutoff temperature” range is from 1300 - 1500 K depending on the hydrocarbon species, as suggested by previous experimental and modeling studies. The comparison between the tracer concentrations using normal and shrouded exhaust valves shows that increased local mixing significantly increased tracer consumption even for the times and temperatures available in the exhaust port.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 43% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.
X