Analysis of influences of injection parameters on combustion process based on 2-stroke rod-less opposed piston diesel engine

• Published in: Applied thermal engineering Vol. 236; p. 121637
• Main Authors: Yang, Jieru, Huang, Zhanqin, Li, Guoxiu, Li, Hongmeng, Hao, Caifeng, Zhang, Cong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 05.01.2024
• Subjects: 2-Stroke Rod-less opposed piston engine; Combustion performance; Injection pressure; Injection timing; Turbulent kinetic energy; CFD; BDC; CA10; CA50; Injection pressure; ATDC; BTDC; Injection timing; TKE; Turbulent kinetic energy; TDC; CA10-90; ϕ; Combustion performance; 2-Stroke Rod-less opposed piston engine
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2023.121637

•A new 2-Stroke Rod-less Opposed Piston (2S-ROPE) diesel engine is proposed.•The various forms of the 2S-ROPE intake and exhaust process are clarified.•The effect of injection timing on the 2S-ROPE combustion process is investigated.•The influence of injection pressure on the 2S-ROPE combustion process is revealed. Global concerns about environmental pollution and fuel consumption are increasing, and as emissions regulations become more stringent, exploring new power and structural forms to optimise diesel engines is the way forward for future breakthroughs in diesel engines. The 2-Stroke Rod-less Opposed Piston (2S-ROPE) has been extensively studied for its vibration-free and simple construction. Compared to conventional four-stroke engines, it has a smaller bore, shorter cycle time, higher power and lower fuel consumption in the same time, making it an ideal power source for small engines. In this paper, the rod-less structure is applied to a two-stroke opposed-piston diesel engine for the first time. Based on experimental verification by spraying, a dynamic high-precision three-dimensional model of computational fluid dynamics (CFD) is established, using lateral injection, to clarify the various airflow patterns that occur in the cylinder during the intake and exhaust of the 2S-ROPE, and investigates the effects of injection timing and injection pressure on the oil–gas mixing and combustion processes in the 2S-ROPE cylinder. The results show that the in-cylinder turbulent kinetic energy is highest at an injection timing of 15° BTDC (Before Top Dead Center) and that fuel injection has the greatest effect on in-cylinder airflow disturbance at this time. At 17.5° BTDC, the duration of in-cylinder combustion was the longest. The effect of injection timing on the burst pressure is linear, for every 2.5° advance, the maximum pressure in the cylinder increases by about 2 MPa. 20 MPa of injection pressure increases, the stall period is shortened by less than 1°, the combustion duration CA10-90 is shortened with the increase in injection pressure, and for every 20 MPa increase in injection pressure, the burst pressure increases by 1 MPa, which is a significant increase.