Infrared multiphoton ignition and combustion enhancement of natural gas

1993 ◽  
Author(s):  
Moshe Lavid ◽  
Arthur T. Poulos ◽  
Suresh K. Gulati
Keyword(s):  
Natural Gas ◽  
Combustion Enhancement ◽  
Ignition And Combustion

scholarly journals Research on the Compression Ignition and Combustion of Natural Gas and Its Reformed Gas

2005 ◽  
Vol 71 (705) ◽  
pp. 1465-1474 ◽  
Author(s):  
Susumu SATO ◽  
Yudai YAMASAKI ◽  
Hideo KAWAMURA ◽  
Norimasa IIDA
Keyword(s):  
Natural Gas ◽  
Compression Ignition ◽  
Ignition And Combustion

Fundamental insights on ignition and combustion of natural gas in an active fueled pre-chamber spark-ignition system

2021 ◽  
Vol 232 ◽  
pp. 111561
Author(s):  
Rajavasanth Rajasegar ◽  
Yoichi Niki ◽  
Jose Maria García-Oliver ◽  
Zheming Li ◽  
Mark P.B. Musculus
Keyword(s):  
Natural Gas ◽  
Spark Ignition ◽  
Ignition System ◽  
Ignition And Combustion

Numerical Studies of Glow Plug Shield on Natural Gas Ignition Characteristics in a CI Engine

2016 ◽  
Author(s):  
Kang Pan ◽  
James S. Wallace
Keyword(s):  
Natural Gas ◽  
Ignition Delay ◽  
Fuel Injection ◽  
Numerical Study ◽  
Direct Injection ◽  
Fuel Mixture ◽  
Injection Angle ◽  
Glow Plug ◽  
Gas Ignition ◽  
Ignition And Combustion

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.

Modeling of Ignition and Combustion for Glow Plug Assisted Direct Injection Natural Gas Engines

2012 ◽  
Author(s):  
Stewart Xu Cheng ◽  
James S. Wallace
Keyword(s):  
Natural Gas ◽  
Heated Surface ◽  
Direct Injection ◽  
Cfd Modeling ◽  
Spontaneous Ignition ◽  
Layer Model ◽  
Glow Plug ◽  
Natural Gas Engines ◽  
Gas Ignition ◽  
Ignition And Combustion

Direct injection natural gas (DING) engines offer the advantages of high thermal efficiency and high power output compared to spark ignition natural gas engines. Injected natural gas requires some form of ignition assist in order to ignite in the time available in a diesel engine combustion chamber. A glow plug — a heated surface — is one form of ignition assist. Simple experiments show that the thickness of the heat penetration layer of a glow plug is very small (≈10−5 m) within the time scale of the ignition preparation period (1–2 ms). Meanwhile, the theoretical analyses reveal that only a very thin layer of the surrounding gases (in micrometer scale) can be heated to high temperature to achieve spontaneous ignition. A discretized glow plug model and virtual gas sub-layer model have been developed for CFD modeling of glow plug ignition and combustion for DING diesel engines. In this paper, CFD modeling results are presented. The results were obtained using a KIVA3 code modified to include the above mentioned new developed models. Natural gas ignition over a bare glow plug was simulated. The results were validated against experiments. Simulation of natural gas ignition over a shielded glow plug was also carried out and the results illustrate the necessity of using a shield. This paper shows the success of the discretized glow plug model working together with the virtual gas sub-layer model for modeling glow plug assisted natural gas direct injection engines. The modeling can aid in the design of injection and ignition systems for glow plug assisted DING engines.

Computational Studies of Glow Plug Ignition of Injected High Pressure Gas Jets

2015 ◽  
Author(s):  
Kang Pan ◽  
James S. Wallace
Keyword(s):  
Natural Gas ◽  
Combustion Chamber ◽  
Ignition Delay ◽  
Numerical Study ◽  
Pressure Rise ◽  
Air Gap ◽  
Time Difference ◽  
Glow Plug ◽  
Gas Ignition ◽  
Ignition And Combustion

A numerical study of ignition and combustion in a glow plug (GP) assisted direct-injection natural gas (DING) engine is presented in this paper. The glow plug is shielded and the shield design is an important part of the combustion system development. The results simulated by KIVA-3V indicated that the ignition delay (ID) predicted by an in-cylinder pressure rise was different from that based on a temperature rise, attributed to the additional time required to burn more fuel to obtain a detectable pressure rise in the combustion chamber. This time difference for the ignition delay estimation can be 0.5 ms, which is significant relative to an ignition delay value of less than 2 ms. To further evaluate the time difference between the two different methods of ignition delay determination, sensitivity studies were conducted by changing the glow plug temperature, and rotating the glow plug shield opening angle towards the fuel jets. The results indicated that the ID method time difference varied from 0.3 to 0.8 ms for different combustion chamber configurations. In addition, this study also investigated the influences of different glow plug shield parameters on the natural gas ignition and combustion characteristics, by modifying the air gap between the glow plug and its shield, and by changing the shield opening size. The computational results indicated that a bigger air gap inside the shield can delay gas ignition, and a smaller shield opening can block the flame propagation for some specific fuel injection angles.

Ignition and Combustion Enhancement of Boron with Polytetrafluoroethylene

2015 ◽  
Vol 31 (1) ◽  
pp. 386-392 ◽  
Author(s):  
Gregory Young ◽  
Colin W. Roberts ◽  
Chad A. Stoltz
Keyword(s):  
Combustion Enhancement ◽  
Ignition And Combustion

Influence of Injection Parameters and Operating Conditions on Ignition and Combustion in Dual-Fuel Engines

2017 ◽  
Author(s):  
Marcus Grochowina ◽  
Michael Schiffner ◽  
Simon Tartsch ◽  
Thomas Sattelmayer
Keyword(s):  
Natural Gas ◽  
High Speed ◽  
Measurement Techniques ◽  
Injection Pressure ◽  
Operating Conditions ◽  
Liquid Fuels ◽  
Dual Fuel ◽  
Injection Parameters ◽  
Pilot Fuel ◽  
Ignition And Combustion

Dual-Fuel (DF) engines offer great fuel flexibility since they can either run on gaseous or liquid fuels. In the case of Diesel pilot ignited DF-engines the main source of energy is provided by gaseous fuel, whereas the Diesel fuel acts only as an ignition source. Therefore, a proper autoignition of the pilot fuel is of utmost importance for combustion in DF-engines. However, autoignition of the pilot fuel suffers from lower compression temperatures of Miller or Atkinson valve timings. These valve timings are applied to increase efficiency and lower nitrogen oxide engine emissions. In order to improve the ignition, it is necessary to understand which parameters influence the ignition in DF-engines. For this purpose, experiments were conducted and the influence of parameters such as injection pressure, pilot fuel quantity, compression temperature and air-fuel equivalence ratio of the homogenous natural gas-air mixture were investigated. The experiments were performed on a periodically chargeable combustion cell using optical high-speed recordings and thermodynamic measurement techniques for pressure and temperature. The study reveals that the quality of the Diesel pilot ignition in terms of short ignition delay and a high number of ignited sprays significantly depends on the injection parameters and operating conditions. In most cases, the pilot fuel suffers from too high dilution due to its small quantity and long ignition delays. This results in a small number of ignited sprays and consequently leads to longer combustion durations. Furthermore, the experiments confirm that the natural gas of the background mixture influences the autoignition of the Diesel pilot oil.

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