Effect analysis of the forward flow fuel injection angle on stratified combustion process in a high-pressure direct injection diesel Wankel engine (HPDI-DWE)

2022 ◽  
Vol 253 ◽  
pp. 115179
Author(s):  
Wei Chen ◽  
Shiwu Yu ◽  
Jianfeng Pan ◽  
Baowei Fan ◽  
Qingsong Zuo ◽  
...  
2008 ◽  
Vol 12 (1) ◽  
pp. 103-114 ◽  
Author(s):  
Dzevad Bibic ◽  
Ivan Filipovic ◽  
Ales Hribernik ◽  
Boran Pikula

An ignition delay is a very complex process which depends on a great number of parameters. In practice, definition of the ignition delay is based on the use of correlation expressions. However, the correlation expressions have very often limited application field. This paper presents a new correlation which has been developed during the research project on the direct injection M-type diesel engine using both the diesel and biodiesel fuel, as well as different values of a static injection timing. A dynamic start of injection, as well as the ignition delay, is defined in two ways. The first approach is based on measurement of a needle lift, while the second is based on measurement of a fuel pressure before the injector. The latter approach requires calculation of pressure signals delay through the fuel injection system and the variation of a static advance injection angle changing. The start of a combustion and the end of the ignition delay is defined on the basis of measurements of an in-cylinder pressure and its point of separation from a skip-fire pressure trace. The developed correlation gives better prediction of the ignition delay definition for the M-type direct injection diesel engine in the case of diesel and biodiesel fuel use when compared with the classic expression by the other authors available in the literature.


Author(s):  
Kang Pan ◽  
James S. Wallace

This paper presents a numerical study on fuel injection, ignition and combustion in a direct-injection natural gas (DING) engine with ignition assisted by a shielded glow plug (GP). The shield geometry is investigated by employing different sizes of elliptical shield opening and changing the position of the shield opening. The results simulated by KIVA-3V indicated that fuel ignition and combustion is very sensitive to the relative angle between the fuel injection and the shield opening, and the use of an elliptical opening for the glow plug shield can reduce ignition delay by 0.1∼0.2ms for several specific combinations of the injection angle and shield opening size, compared to a circular shield opening. In addition, the numerical results also revealed that the natural gas ignition and flame propagation will be delayed by lowering a circular shield opening from the fuel jet center plane, due to the blocking effect of the shield to the fuel mixture, and hence it will reduce the DING performance by causing a longer ignition delay.


2000 ◽  
Vol 123 (3) ◽  
pp. 413-424 ◽  
Author(s):  
M. J. van Nieuwstadt ◽  
I. V. Kolmanovsky

Modern direct injection engines feature high pressure fuel injection systems that are required to control the fuel quantity very accurately. Due to limited manufacturing accuracy these systems can benefit from an on-line adaptation scheme that compensates for injector variability. Since cylinder imbalance affects many measurable signals, different sensors and algorithms can be used to equalize torque production by the cylinders. This paper compares several adaptation schemes that use different sensors. The algorithms are evaluated on a cylinder-by-cylinder simulation model of a direct injection high speed diesel engine. A proof of stability and experimental results are reported as well.


2020 ◽  
pp. 146808742093135
Author(s):  
Tianbo Wang ◽  
Lanchun Zhang ◽  
Shaoyi Bei ◽  
Zhongwei Zhu

In order to improve the control precision of in-cylinder mixing and combustion process, and to avoid the engine power drop because of the port fuel injection mode, it becomes a tendency to inject gas fuel into cylinder directly, with the help of the high-pressure gas-fueled injection device. However, considering that the mixing speed of gas fuel with air is usually slower than that of gasoline or diesel, the gas fuel direct injection mode tends to cause poor mixing performance and insufficient combustion in engine. Based on this situation, in-cylinder mixing process of direct injection gas–fueled engine is taken as the research object in this article. The three-dimensional transient computational fluid dynamics model of the injection and mixing process in gas-fueled direct injection engine is established to analyze the effects of the poppet valve opening manner and injection timing on the in-cylinder mixing homogeneity. The results indicate that delaying the injection timing can improve the wall impact strength and help to form a tumble flow in the cylinder. The stronger wall impact and tumble flow can reverse the natural diffusion law and greatly improve the in-cylinder mixing effect. Under the same injection timing conditions, although the pull-open valve has a larger injection penetration distance, the in-cylinder mixing effect is still worse than the push-open one. This is because, for the push-open valve, the fuel jet will be around the slope of the valve, which is beneficial to improve the mixing effect.


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