How to Put the HCCI Engine to Practical Use: Control the Ignition Timing by Compression Ratio and Increase the Power Output by Supercharge

Author(s):  
Zhili Chen ◽  
Konno Mitsuru
2002 ◽  
Author(s):  
Jan-Ola Olsson ◽  
Per Tunestål ◽  
Bengt Johansson ◽  
Scott Fiveland ◽  
Rey Agama ◽  
...  

2011 ◽  
Vol 110-116 ◽  
pp. 273-277
Author(s):  
Rahim Ebrahim ◽  
Mahmoud Reza Tadayon ◽  
Farshad Tahmasebi Gandomkari ◽  
Kamyar Mahbobian

Today, the world community is looking for fuel efficient and environmentally viable alternatives for many of the traditional energy conversion approaches. This development has further worked to increase the technical focus on conventional cycles for making them more optimum in terms of performance. Hence, the objective of this paper is to study the effect of ethanol-air equivalence ratio on the power output and the indicated thermal efficiency of an air standard Otto cycle. Optimization of the cycle has been performed for power output as well as for thermal efficiency with respect to compression ratio. The results show that the maximum power output, the optimal compression ratio corresponding to maximum power output point, the optimal compression ratio corresponding to maximum thermal efficiency point and the working range of the cycle first increase and then decrease as the equivalence ratio increases. The result obtained herein provides a guide to the performance evaluation and improvement for practical Otto engines.


Author(s):  
M. Paloboran ◽  
H. Syam ◽  
M. Yahya ◽  
Darmawang

This research aims to improve the combustion performance of gasoline-bioethanol fuel blended in the ratio of 50:50 (E50) on the spark-ignition engine by employing a new combustion strategy. The Box Behnken Design of Response Surface Methodology and Non-Linear Programming was employed to optimize the performance of the engine and create some engine parameters. The performance of the engine consists of power, torque, thermal efficiency, fuel consumption, and the emission of CO and HC, while the engine and combustion parameters are compression ratio, ignition timing, and engine speed. A new combustion strategy will be applied in this study with a tiered mapping process for each engine parameter based on the MBT. The brake torque increased by 13.5 % while HC and CO emissions decreased by 15 % and 71 % respectively when the combustion strategy applied if compared o the pure gasoline in engine standard condition. Furthermore, the BSFC increased by 33 % while BTE decreased by 15 % towards the gasoline fuel. The non-linear programming applied in this study intended to figure out the best combination of the engine parameters in obtaining optimum engine performances. In the RSM analysis, the codes --1, 0, 1 represented 12, 12.5, and 13 of compression ratio, 16, 20, and 24 BTDC of ignition timing and 2000, 5000, and 8000 rpm of engine speed. Therefore, 20 BTDC of ignition timing and 13:1 of compression ratio is the optimum engine parameters used in gaining the optimal performance of the engine when E50 runs in SI-PFI engine of 150 cm3


2020 ◽  
Vol 8 (6) ◽  
pp. 459 ◽  
Author(s):  
La Xiang ◽  
Gerasimos Theotokatos ◽  
Haining Cui ◽  
Keda Xu ◽  
Hongkai Ben ◽  
...  

Both spark ignition (SI) natural gas engines and compression ignition (CI) dual fuel (DF) engines suffer from knocking when the unburnt mixture ignites spontaneously prior to the flame front arrival. In this study, a parametric investigation is performed on the knocking performance of these two engine types by using the GT-Power software. An SI natural gas engine and a DF engine are modelled by employing a two-zone zero-dimensional combustion model, which uses Wiebe function to determine the combustion rate and provides adequate prediction of the unburnt zone temperature, which is crucial for the knocking prediction. The developed models are validated against experimentally measured parameters and are subsequently used for performing parametric investigations. The derived results are analysed to quantify the effect of the compression ratio, air-fuel equivalence ratio and ignition timing on both engines as well as the effect of pilot fuel energy proportion on the DF engine. The results demonstrate that the compression ratio of the investigated SI and DF engines must be limited to 11 and 16.5, respectively, for avoiding knocking occurrence. The ignition timing for the SI and the DF engines must be controlled after −38°CA and 3°CA, respectively. A higher pilot fuel energy proportion between 5% and 15% results in increasing the knocking tendency and intensity for the DF Engine at high loads. This study results in better insights on the impacts of the investigated engine design and operating settings for natural gas (NG)-fuelled engines, thus it can provide useful support for obtaining the optimal settings targeting a desired combustion behaviour and engine performance while attenuating the knocking tendency.


Energy ◽  
2019 ◽  
Vol 175 ◽  
pp. 410-422 ◽  
Author(s):  
Yasin Şöhret ◽  
Habib Gürbüz ◽  
İsmail Hakkı Akçay

Author(s):  
G. H. Choi ◽  
J. H. Kim ◽  
Christian Homeyer

Since the early 20th century, most ground vehicles are driven with gasoline and diesel. The degradation of the environment affects human on earth unless the quality of the air is improved. One of the alternative fuels, LPG, is potentially capable of lowering vehicular emissions when compared to gasoline or diesel. There is a penalty in power output resulting from the use of LPG because the engine can induce less amount of air with Mixer system comparing with gasoline engine. Currently, the liquid-phase LPG is injected into the intake port of the engine, the fuel vaporizes enroute to the combustion chamber. Therefore, the performance and combustion processes of the tested engine are investigated with different LPG fuel systems. The test engine was developed and named heavy-duty VACRE. The test engine for this work operates 1400rpm with MBT conditions. The major conclusions of the work include; 1) The power output of LPi system with liquid-phase is approximately 17% higher than that of vapor-phase Mixer system due to increases of volumetric efficiency. And the MBT spark timing of LPi system is approximately 25% more advanced than that of Mixer system at λ value 1.0; 2) The LPi system shows both the maximum heat release rate and the cumulative heat release to be approximately 20% higher than the Mixer system; 3) Maximum cylinder pressure decrease with increase of compression ratio and a point of maximum cylinder pressure is delayed with high compression ratio.


2009 ◽  
Author(s):  
Toru Kitamura ◽  
Junichi Takanashi ◽  
Yasuhiro Urata ◽  
Ken Ogawa

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