Effect of asymmetric fuel injection on combustion characteristics and NOx emissions of a hydrogen opposed rotary piston engine. (1st January 2023)

• Record Type: Journal Article
• Authors: Huang, Junfeng; Gao, Jianbing; Wang, Yufeng; Yang, Ce; Ma, Chaochen; Tian, Guohong
• Is Part Of: Energy. Volume 262:Part B(2023)
• Publication Date: 2023-01-01
• Subjects: Opposed rotary piston engine -- Direct hydrogen injection -- Asymmetrical injector layout -- Combustion characteristics -- NO emission; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2022.125544
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Opposed rotary piston engines have the characteristics of high-power density and simple mechanisms. The applications of hydrogen fuel to internal combustion engines significantly are without carbon dioxide emission, alleviating the global warming. In this paper, hydrogen fuel was asymmetrically injected into combustion chambers to increase hydrogen penetration distance via; in the meantime, the engine performance and nitrogen monoxide (NO) emission with different ignition timing are explored by numerical simulation method. The symmetrical fuel injection scenario was provided as a baseline. In the scenarios of asymmetrical fuel injection, the engine had the best hydrogen injector position and ignition timing. Peak in-cylinder pressure P max reached 56.0 bar under ignition timing t i of −14.2° CA before top dead centre (bTDC) and hydrogen injector position ( θ 2 ) of 60.5°; in the meantime, heat loss rate H L and heat release rate Q r reached maximum values. Compared with the symmetric fuel injection engine, the peak NO emission of the asymmetric fuel injection engine was reduced by 15%. The proportions of energy loss by cylinder walls of asymmetric fuel injection engine were low and showed low dependency on ignition timing and hydrogen injector layout. Additionally, the asymmetric hydrogen injection structure makes hydrogen distribute evenly in the combustion chamber. Graphical abstract: Image 1 Highlights: Asymmetric hydrogen injection engine has best injector position and ignition timing. The energy loss by cylinder walls of asymmetric hydrogen injection engine is lower. Asymmetric hydrogen injection structure can reduce NOx emission of ORP engine. Asymmetric hydrogen injection structure makes hydrogen distribute evenly.