Dual-pulse laser ignition of ethylene-air mixtures in a supersonic combustor

被引：13

作者：

Yang, Leichao ^{[1
]}

An, Bin ^{[2
]}

Liang, Jianhan ^{[1
]}

Li, Xipeng ^{[1
]}

Wang, Zhenguo ^{[1
]}

机构：

[1] Natl Univ Def Technol, Coll Aerosp Sci & Engn, Changsha 410073, Hunan, Peoples R China

[2] Natl Univ Def Technol, Sci & Technol Scramjet Lab, Changsha 410073, Hunan, Peoples R China

来源：

OPTICS EXPRESS | 2018年 / 26卷 / 07期

基金：

美国国家科学基金会;

关键词：

INDUCED PLASMA IGNITION; SPARK-IGNITION; ENERGY; ENGINE; FLOW;

D O I：

10.1364/OE.26.007911

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

To reduce the energy of an individual laser pulse, dual-pulse laser ignitions (LIs) at various pulse intervals were investigated in a Mach 2.92 scramjet engine fueled with ethylene. For comparison, experiments on a single-pulse LI were also performed. Schlieren visualization and high-speed photography were employed to observe the ignition processes simultaneously. The results indicate that the energy of an individual laser pulse can be reduced by half via a dual-pulse LI method as compared with a single-pulse LI with the same total energy. The reduction of the individual laser pulse energy degrades the requirements on the laser source and the beam delivery system, which facilitates the practical application of LI in hypersonic vehicles. A pulse interval shorter than 40 mu s is suggested for dual-pulse LI in the present study. Because of the intense heat loss and radical dissipation in high-speed flows, the pulse interval for dual-pulse LI should be short enough to narrow the spatial distribution of the initial flame kernel. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

引用

页码：7911 / 7919

页数：9