scholarly journals Effects of increased spark discharge energy and enhanced in-cylinder turbulence level on lean limits and cycle-to-cycle variations of combustion for SI engine operation

2017 ◽  
Vol 205 ◽  
pp. 1467-1477 ◽  
Author(s):  
Dongwon Jung ◽  
Kosaku Sasaki ◽  
Norimasa Iida
2012 ◽  
Vol 5 (2) ◽  
pp. 547-559 ◽  
Author(s):  
Bjoern Hoepke ◽  
Stefan Jannsen ◽  
Emmanuel Kasseris ◽  
Wai K. Cheng
Keyword(s):  

2018 ◽  
Vol 21 (3) ◽  
pp. 368-373
Author(s):  
Kadhim Fadhil Nasir

The consequence of mixing pure ethanol with gasoline on the pollution and performance of SI engine are investigated experimentally in the existent study. The SI engine that employed in the experiment is a single cylinder four stroke. Analysis is carried out for engine operation parameter, CO2, CO and unburned HC productions. The measurements are recorded for several engine speeds from 1500 – 3000 rpm with load and ethanol addition of (0E, 10E, 20E, 30E, 40E, 50E,). The results displayed increasing in brake power, and brake thermal efficiency while the brake specific fuel consumption decreases when the ethanol- gasoline blends fuel increases. Also it was found that CO, HC, and CO2 concentrations decrease when the ethanol- gasoline increases. The best results obtained in the study is for the blend of E-50.


Author(s):  
Zhenyi Yang ◽  
Xiao Yu ◽  
Hua Zhu ◽  
David S-K Ting ◽  
Ming Zheng

The enhancement of the breakdown power during the spark discharge process has been proved to be beneficial for the flame kernel formation process under lean/diluted conditions. Such a strategy is realized by using a conventional transistor coil ignition system with an add-on capacitance in parallel to the spark plug gap in this paper. In practical application, the use of different ceramic material other than aluminum oxide can change the parasitic capacitance of the spark plug, achieving similar effect in terms of rescheduling the discharge energy released during the breakdown phase. Detailed research has been carried out to investigate the effect of the parallel capacitance and the cross flow velocity on the flame kernel formation and propagation process. With the increase in parallel capacitance, more spark energy is delivered during the breakdown phase, while less energy is released during the arc/glow phase. Shadowgraph images of the spark plasma reveal that the high-power spark discharge can generate a larger high-temperature area with enhanced electrically prompted turbulence under quiescent conditions, as compared with that using the conventional transistor coil ignition discharge strategy under the same condition. The breakdown enhanced turbulence of the high-power spark is proved to be beneficial for the flame kernel development, especially with the lean or exhaust gas recirculation diluted combustible mixtures, given that sufficient spark energy is available for the high-power spark strategy to successfully generate the breakdown event. The results of combustion tests under flow conditions reveal that the breakdown enhanced turbulence of the high-power spark tends to be overshadowed by the turbulence generated from the flow field, and both the increase in flow velocity and parallel capacitance contribute to the reduction in discharge duration of the arc/glow phase. Therefore, the benefits brought about by the high-power spark discharge tend to diminish with the intensification of flow velocity.


2001 ◽  
Author(s):  
Kazimierz Golec ◽  
Tadeusz Papuga ◽  
Maciej Makowski ◽  
Tomasz Markiewicz

2007 ◽  
Vol 131 (4) ◽  
pp. 33-41
Author(s):  
Piotr JAKLIŃSKI ◽  
Łukasz GRABOWSKI ◽  
Mirosław WENDEKER ◽  
Jacek CZARNIGOWSKI ◽  
Piotr SZCZĘSNY ◽  
...  

The paper presents results of experiments on operation parameters of a 4-cylinder Holden 2.0 MPFI engine, supplied with LPG by means of sequential intake-manifold injection system, in the function of the distance between the injection ferrule and the cylinder’s inlet valve. Four positions of the injection ferrule along the manifold were tested, i.e. 115, 170, 230 and 310 mm from the valve. Indicated pressure, peak pressure and toxic emissions, in the function of injection start angle, were analyzed and compared for each position. The importance of the distance between injection ferrule and inlet valve was proved.


2021 ◽  
Author(s):  
Zbigniew Żmudka ◽  
Stefan Postrzednik

The article presents theoretical research of the proposed system of fully independent valve control (FIVC) of the SI engine. The analysis included controlling the movement of the intake valves, which results in adjusting the mass of the fresh charge to the current engine load, as well as the movement of the exhaust valves, where the main aim is to keep the rest of the exhaust gas in the cylinder, i.e. implementation of internal EGR. The open theoretical Seiliger-Sabathe cycle with the classic throttle regulation of load is the reference cycle for assessment of benefits and study of the effectiveness of obtaining work as a result of application of the FIVC system. A comparative analysis of the effectiveness of application of the proposed system was carried out based on the selected quantities: fuel dose, cycle work, relative work of charge exchange and cycle efficiency. The use of the FIVC to regulate the SI engine load makes it possible to eliminate the throttle and thus reduce the charge exchange work, especially in the partial load range. And this then leads to an increase in internal and effective work, which in turn results in an increase in the effective energy efficiency of an engine operation.


Sign in / Sign up

Export Citation Format

Share Document