Analysis of pre-ignition to super-knock: Hotspot-induced deflagration to detonation. (15th March 2015)

• Record Type: Journal Article
• Authors: Wang, Zhi; Qi, Yunliang; He, Xin; Wang, Jianxin; Shuai, Shijing; Law, Chung K.
• Is Part Of: Fuel. Volume 144(2015)
• Page Start: 222
• Page End: 227
• Publication Date: 2015-03-15
• Subjects: Combustion -- Pre-ignition -- Super-knock -- Deflagration -- Detonation; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2014.12.061
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Detonation in super-knock was demonstrated for the first time by optical diagnostics. Pre-ignition was captured under high temperature and high pressure conditions. Detonation is initiated in the unburned mixture for closed system. High pressure oscillation induced by detonation. Super-knock mechanism was proposed as DDP. Abstract: Occurrence of sporadic super-knock is the main obstacle in the development of advanced gasoline engines. By utilizing a rapid compression machine, events of pre-ignition and super-knock in a closed system under high temperature and high pressure were captured by synchronous high-speed direct photography and pressure measurement, with the results demonstrating that the mechanism of super-knock is constituted by hotspot-induced deflagration to detonation followed by high-pressure oscillation (DDP).