Behavior of Fuel Spray Injected by Tailpipe Injector for Post Treatment of Diesel Engine Emissions (Second Report)

-Analysis of Impingement Spray on a Flat Wall under Various Ambient Conditions -

Abstract

Injected fuels into the exhaust line upstream of the Diesel Oxidation Catalyst (DOC), hydrocarbons are oxidized on the DOC, which increases the exhaust gas temperature at the DPF inlet as one system to regenerate the DPF. Under this system, ensuring complete evaporation and an optimum mixture distribution in the exhaust line is important. This report focuses on free spray and impingement spray to understand its physical phenomena using scattered light method, Super High Spatial Resolution Photography (SHSRP) and PIV with swirl nozzle and n-dodecane. As a result, the breakup mechanism of swirl nozzle under low injection pressure is different from Fraser's theories and break up is irregular due to the instability of the liquid film. Also it is confirmed that the follow up spray is a feature of the swirl nozzle.