Numerical study on the effect of spray included angle and swirl ratio on combustion and emissions of a marine diesel engine under post injection strategy Tianjin Univ

Format:

Book

Conference/Event

Author/Creator:

Zhao, Changpu, author.

Contributor:

Bian, Zhishang

Kong, Shiru

Conference Name:

SAE Powertrains, Fuels & Lubricants Digital Summit (2021-09-28 : Live Online, Pennsylvania, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2021

Summary:

This study conducts a numerical study to investigate the individual effect and their interaction of three post injection duration angles (3°CA, 5°CA and 7°CA), four spray included angles (145°, 150°, 155° and 160°) and four swirl ratios (0.5, 0.85, 1.2 and 1.6) in a marine diesel engine with main-post injection. Combustion performance and exhaust emissions of NOx and soot are simulated and analyzed by using AVL-FIRE code. Results show that decreasing post injection duration angle from 7°CA to 3°CA shortens the combustion duration and drops soot emission by 13.2%, while induces a slight increase in NOx emissions by 1.0%. Spray included angle changing the spray targeting position within the combustion chamber. Wider spray included angle gets rise to the peak value of in-cylinder pressure by 1%, drops ISFC by 2.9%, and significantly declines soot emission by 49.6%. The intermediate spray included angle of 150° is the most suitable in reduction of NOx emissions. Swirl ratio represents the intensity of air flow movement around the axis of cylinder. Larger swirl ratio decreases ignition delay, while increases combustion duration. An appreciated swirl ratio of 0.5 achieves simultaneously reduction in NOx emissions and soot emission. To sum up, there are 13 cases that break the traditional NOx-soot trade-off as both NOx and soot emissions are dropped with optimized post injection duration angle, spray included angle and swirl ratio, in comparison with the original engine. Furthermore, an optimization procedure of case D3-A160-S0.5 is conducted, which produces the best performance in emissions and fuel consumption by simultaneously decreasing NOx emissions by 30.4%, soot emission by 34.6%, and ISFC by 0.7%

Notes:

Vendor supplied data

Publisher Number:

2021-01-1169

Access Restriction:

Restricted for use by site license