定容燃烧弹内闪沸燃烧研究

doi:10.19562/j.chinasae.qcgc.2024.03.011

摘要/Abstract

摘要：

闪沸喷雾作为一种相变喷雾形式，在替代燃料和零碳燃料的燃烧方面具有重要意义。然而当前的研究大部分集中在喷雾形态研究上，对燃烧机理的研究较少。故本文使用定容燃烧弹对稀薄条件下的闪沸喷雾雾化和燃烧过程进行分析，重点研究闪沸喷雾特性、混合气着火特性、火焰传播特性和燃烧放热特性。结果表明，闪沸喷雾能有效降低着火延迟，提升火焰传播速度，从而有利于能量转换，实现更高的放热率和更高的放热量。并且闪沸喷雾火焰前端形状更加规则，表明更加稳定的火焰传播，有助于提升发动机的热效率和稀燃条件下的燃烧稳定性。

关键词: 闪沸喷雾雾化, 稀薄燃烧, 定容燃烧弹, 高速成像

Abstract:

Flash boiling spray， as a form of phase-changing spray， plays an important role in the combustion of alternative fuels and zero-carbon fuels. However， most of the current researches focus on the spray morphologies， and there are few studies on the fundamental combustion mechanism. Therefore， the constant volume combustion chamber （CVCC） is used in this paper to analyze the atomization and combustion process of flash boiling spray under lean conditions， focusing on the characteristics of flash boiling spray， mixture ignition and flame kernel development， flame propagation and heat release characteristics. The results show that flash boiling spray can effectively reduce ignition delay and increase flame propagation speed， which is beneficial to energy conversion thus achieving higher heat release rate and larger cumulative heat release. Moreover， the flame front shape of flash boiling combustion is more regular， which suggests more stable flame propagation which is helpful to improve engine thermal efficiency as well as combustion stability under lean burn conditions.

Key words: flash boiling spray, lean burn, constant volume combustion chamber, high-speed color imaging

罗徐霖,李岩松,崔明利,孔令逊,李雪松,许敏. 定容燃烧弹内闪沸燃烧研究[J]. 汽车工程, 2024, 46(3): 476-482.

Xulin Luo,Yansong Li,Mingli Cui,David L.S. Hung,Xuesong Li,Min Xu. An Investigation of Flash Boiling Spray Combustion in a Constant Volume Combustion Chamber[J]. Automotive Engineering, 2024, 46(3): 476-482.

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参数	数值
喷油器类型	GDI 两孔
燃料喷射压力/MPa	5
燃料类型	汽油（辛烷 No. 92）
点火电压/kV	80
点火电流/mA	20
点火持续时间/s	20
点火起始时间/ms	500
当量比	0.85
环境压力/kPa	40， 100， 160
燃料温度/℃	30， 120

环境压力	40 kPa	100 kPa	160 kPa
总喷油量	0.077 4 g	0.196 8 g	0.314 9 g
喷射次数	12	31	48
喷射脉宽（30 ℃）	1.954 ms	1.892 ms	1.954 ms
喷射脉宽（120 ℃）	2.08 ms	2.01 ms	2.08 ms