Study on combustion characteristics and particulate emissions of a common-rail diesel engine fueled with n-butanol and waste cooking oil blends. Issue 3 (June 2019)

• Record Type: Journal Article
• Authors: Geng, Limin; Chen, Yang; Chen, Xubo; Lee, Chia-fon F.
• Is Part Of: Journal of the Energy Institute. Volume 92:Issue 3(2019)
• Page Start: 438
• Page End: 449
• Publication Date: 2019-06
• Subjects: Butanol -- Biodiesel -- Combustion characteristics -- Soot emission -- Ultrafine particles; Power (Mechanics) -- Periodicals; Power resources -- Periodicals; Fuel -- Periodicals; 621.04205
• DOI: 10.1016/j.joei.2018.05.004
• Languages: English
• ISSNs: 1743-9671

Abstract

Abstract: Biodiesel is a promising alternative fuel because of its renewability and extensive source of raw materials. Butanol can be blended in biodiesel to reduce the kinematic viscosity and promote the fuel atomization. In this respect, biodiesel was blended with 10% and 20% n-butanol, and the combustion characteristics and particulate emissions of the fuel blends were tested in a turbocharged, 6-cylinder, common rail diesel engine at a constant speed of 1400 rpm under seven engine loads. The experimental results show that under various engine loads, all of the butanol and biodiesel fuel blends provide faster combustion than diesel due to the higher oxygen content of n-butanol and the lower cetane number of butanol which results in stronger premixed combustion. The addition of butanol is beneficial to concentrating the heat release and thus shorten the combustion duration. With an increased proportion of butanol, soot emissions of butanol and biodiesel fuel blends decrease, the number concentration and volume concentration of ultrafine particles (UFPs) reduce noticeably. Meanwhile, the geometric mean diameters of UFPs decrease with an increase in butanol. With an increase of the engine loads, the number concentration peaks of UFPs gradually transfer from the size range of nucleation mode particles (NMPs) to the size range of accumulation mode particles (AMPs) due to the elevated combustion temperatures and high equivalence ratios. Moreover, biodiesel and fuel blends exhibit a higher percentage of NMPs as compared to diesel because of the fuel-bound oxygen, zero aromatics, and low sulfides. Highlights: PM emissions of butanol/biodiesel blends were studied on a common rail diesel engine. Butanol contributed to concentrate heat release and shorten combustion duration. The number concentrations of UFPs reduce with an increased proportion of butanol. Butanol/biodiesel fuel blends exhibit higher percentage of NMPs as compared to diesel. Number concentration peaks of UFPs transfer from NMPs to AMPs as increasing engine loads.