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ZI Xinyun
JIANG Dahai
DENG Chenglin
Department of Automotive Engineering,
Tianjin Traffic Institute,
Tianjin 300161, China
OUYANG Minggao
YANG Fuyuan
Department of Automotive Engineering, Tsinghua University,
Beijing 100084, China
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EFFECTS OF INJECTION STRATEGY ON D. I.
DIESEL ENGINE COMBUSTION*
Abstract:
Experiments are conducted to develop an understanding of how
split injections can affect the combustion and emission
characteristics of a D. I. diesel engine with a common-rail
injection system. The ratio of the amount of fuel injected
between two injection pulses and the injection interval is
varied keeping the injected fuel quantity constant. Results show
that under the 70D90-10 injection pattern, the engine achieves
the lower NOx-smoke emissions and BSFC
compared with the single injection pattern. The heat release
rate and the temperature show that the split injections increase
the initial premixed burn and retards the diffusion burn. With
the balance of these two effects, the maximum in-cylinder
temperature decreases while the 50% heat release point is held
at almost the same crank angle. Therefore, both NOx
emission and BSFC are improved while keeping the smoke emission
at the same level.
Key words:
Diesel engine High pressure common rail Split injections
Emission |