EVCT对直喷汽油机燃烧和微粒排放的影响

doi:10.19562/j.chinasae.qcgc.2022.05.007

摘要/Abstract

摘要：

本文研究了排气门关闭正时（EVCT）耦合点火正时（IT）对火花点火汽油直喷（GDI）发动机在５种不同工况下燃烧、性能和微粒排放的影响。研究结果表明，EVCT的延迟导致燃烧持续期（CA5-CA90）延长和燃烧中心（CA50）延迟。而IT的提前可以提前CA50，缩短燃烧持续期。EVCT结合IT可有效改善发动机油耗和微粒排放，有效燃油消耗率（BSFC）可降低4.66%，微粒总数最多可减少95%。随着负荷或转速的增加，EVCT对微粒排放和燃料消耗的影响减弱。

关键词: 直喷汽油机, 可变气门正时, 点火提前角, 微粒, 发动机性能

Abstract:

This paper studies the effect of exhaust valve closing timing （EVCT） coupled with ignition timing （IT） on combustion， performance and particulate emissions of spark-ignited gasoline direct injection （GDI） engines under five different operating conditions. The results of the study show that the delay of EVCT leads to prolonged combustion duration （CA5-CA90） and delayed combustion center （CA50）. The advancement of IT can advance CA50 and shorten the combustion duration. EVCT combined with IT can effectively reduce engine fuel consumption and particulate emission， with a reduction of brake specific fuel consumption（BSFC） by 4.66% and the total number of particulates by up to 95%. With the increase of the load or speed， the impact of EVCT on particulate emissions and fuel consumption weakens.

Key words: direct injection gasoline engine, variable valve timing, ignition advance angle, particulates, engine performance

解方喜,孟祥龙,刘宇,李晓娜,张玉林,冯海洲. EVCT对直喷汽油机燃烧和微粒排放的影响[J]. 汽车工程, 2022, 44(5): 701-708.

Fangxi Xie,Xianglong Meng,Yu Liu,Xiaona Li,Yulin Zhang,Haizhou Feng. EVCT on Combustion and Particulate Emission of Direct Injection Gasoline Engine[J]. Automotive Engineering, 2022, 44(5): 701-708.

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发动机参数	数值
型式	4气门，直列，4缸
排量/L	1.39
缸径×冲程/mm	76.5×75.6
压缩比	10.0
喷射形式	GDI
最大转矩/（N·m）	220
额定功率/kW	100

工况	发动机转速/ （r·min^-1）	点火提前角/ （?CA BTDC）	排气关闭正时/ （?CA ATDC）	转矩/ （N·m）
1	1 500	15-36	363.25-403.25	30
2	1 500	15-36	363.25-403.25	50
3	1 500	15-36	363.25-403.25	100
4	2 000	15-36	363.25-403.25	50
5	3 000	15-36	363.25-403.25	50

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