Study on ignition temperature conditions and influencing factors of lean burn spark assisted compression ignition

doi:10.3969/j.issn.1674-8484.2021.02.012

Abstract

Abstract:

The ignition conditions and influencing factors of auxiliary compression ignition were studied to realize the control towards the moment of fire and to decouple the influence of key control parameters on the degree of compression combustion and the moment of compression combustion. Under the condition of negative valve overlap angle by using small lift camshaft and the air excess coefficient was 1.2, the experiments and calculations were carried out. The results show that the compression burning rate can be defined by the proportion of the heat released in the circulation compression burning part relative to that of the circulation emission, which can reflect the degree of compression burning. The compression burning rate can be reflected by the key control parameters such as the effective compression ratio, exhaust gas recirculation (EGR) rate and ignition advanced angle, which are the analytic relationship of independent variables. The temperature 958.13(±15) K of the unburned part of mixed gas at the moment of compression combustion is given as the ignition temperature. In a word, the influencing factors of the compression combustion rate can be decomposed into operation parameters and structural parameters. For a specific parameter, through the analytic formulation of the relationship between the compression combustion rate and key control parameters, the fire-timing can be predicted and controlled.

Key words: gasoline engine, auxiliary compression ignition, effective compression ratio, exhaust gas recirculation (EGR), compression ignition rate

CLC Number:

TK411.2

SUN Jian, GENG Lu, LAI Haipeng, GAO Dingwei, YU Shuhai. Study on ignition temperature conditions and influencing factors of lean burn spark assisted compression ignition[J]. Journal of Automotive Safety and Energy, 2021, 12(2): 232-242.

Figures/Tables 22

References 15

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气缸数	4
排量	1.998 L
缸径×行程	82 mm × 94.6 mm
几何压缩比	14
燃油喷射形式	中置直喷
喷射压力	35 MPa
点火能量	90 mJ
最大爆发压力	12 MPa
气道滚流比/流量系数	2.337 / 0.349
进气凸轮包角,CA	175°
排气凸轮包角,CA	145°
进气门升程	6 mm
排气门升程	4 mm

气缸数	4
排量	1.998 L
缸径×行程	82 mm × 94.6 mm
几何压缩比	14
燃油喷射形式	中置直喷
喷射压力	35 MPa
点火能量	90 mJ
最大爆发压力	12 MPa
气道滚流比/流量系数	2.337 / 0.349
进气凸轮包角,CA	175°
排气凸轮包角,CA	145°
进气门升程	6 mm
排气门升程	4 mm