scholarly journals RESEARCH OF THE SI ENGINE WITH MULTISPARK CAPACITOR DISCHARGE IGNITION SYSTEM

2014 ◽  
Vol 46 (1) ◽  
pp. 104-115
Author(s):  
Audris Šimakauskas
Keyword(s):  
Alternative Fuels ◽  
Block Diagram ◽  
Fuel Mixture ◽  
Management Systems ◽  
Si Engine ◽  
Capacitor Discharge ◽  
Ignition System ◽  
Discharge Ignition ◽  
Discharge Duration ◽  
Fuel Mixtures

Modern ignition systems for spark ignition (SI) engine management systems require an extended (adaptive) spark with regulated spark discharge duration for reliable ignition of fuel mixture and elimination of misfired-cycles. Lean air-fuel mixtures and alternative fuels also require an improved ignition system. In order to meet the increased requirements for ignition systems there is a multispark capacitor discharge ignition (CDI) system developed with prolonged spark duration. Block diagram of CDI system is presented; the principle of the operation of the system elements is explained. Mathematical model of the processes of the CDI system are developed. Calculations of the CDI system, test data with four-stroke SI engine GA14DS (Nissan Sunny) and conclusions are presented.

Measurements of Laminar Flame Speeds of Alternative Gaseous Fuel Mixtures

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Ahmed S. Ibrahim ◽  
Samer F. Ahmed
Keyword(s):  
Carbon Dioxide ◽  
Alternative Fuels ◽  
Laminar Flame ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Gaseous Fuel ◽  
Combustion Engines ◽  
Liquefied Petroleum Gas ◽  
Ambient Conditions ◽  
Fuel Mixtures

Global warming and the ever increasing emission levels of combustion engines have forced the engine manufacturers to look for alternative fuels for high engine performance and low emissions. Gaseous fuel mixtures such as biogas, syngas, and liquefied petroleum gas (LPG) are new alternative fuels that have great potential to be used with combustion engines. In the present work, laminar flame speeds (SL) of alternative fuel mixtures, mainly LPG (60% butane, 20% isobutane, and 20% propane) and methane have been studies using the tube method at ambient conditions. In addition, the effect of adding other fuels and gases such as hydrogen, oxygen, carbon dioxide, and nitrogen on SL has also been investigated. The results show that any change in the fuel mixture composition directly affects SL. Measurements of SL of CH4/LPG–air mixtures have found to be about 56 cm/s at ø = 1.1 with 60% LPG in the mixture, which is higher than SL of both pure fuels at the same ø. Moreover, the addition of H2 and O2 to the fuel mixtures increases SL notably, while the addition of CO2/N2 mixture to the fuel mixture, to simulate the EGR effect, decreases SL of CH4/LPG–air mixtures.

Development of a Long Duration Capacitive Discharge Ignition System

2002 ◽  
Author(s):  
Keith Brooks ◽  
Joe Lepley
Keyword(s):  
Slow Speed ◽  
Engine Emissions ◽  
Discharge System ◽  
Capacitor Discharge ◽  
Ignition System ◽  
Compression Stroke ◽  
Lower Total Cost ◽  
Long Duration ◽  
Discharge Ignition ◽  
Test Engine

The development and testing of a new long secondary duration capacitor discharge ignition system is described. Results obtained on a large-bore, slow speed, 2-stroke test engine are described and compared to the results obtained by a commercially available capacitor discharge (CD) single-strike and double-strike ignition system. These tests are conducted under rated full load conditions and high boost lean operation. Engine emissions, fuel consumption, and misfire rates are analyzed and compared in order to determine if such a product merits commercialization. It has been previously demonstrated that multi-strike ignition systems (four strikes per compression stroke) can offer significant reductions in emissions and misfire rate in large-bore slow speed engines field retrofitted to increased boost lean operation for much lower costs than physical modifications to the heads to accommodate prechambers and fuel systems modifications. The work described here utilizes single and double-strike systems (two strikes per compression stroke) with lower energy than previous tests and lower total cost. The extended spark system tested is a proprietary development capacitor discharge system offering the benefits of capacitor discharge design with extremely long duration.

Ultra-Low Emission Hydrogen/Syngas Combustion With a 1.3 MW Injector Using a Micro-Mixing Lean-Premix System

2011 ◽  
Author(s):  
Brian Hollon ◽  
Erlendur Steinthorsson ◽  
Adel Mansour ◽  
Vincent McDonell ◽  
Howard Lee
Keyword(s):  
Carbon Dioxide ◽  
Natural Gas ◽  
Flame Temperature ◽  
Fuel Mixture ◽  
Full Scale ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Fuel Injector ◽  
Nitrogen Dilution ◽  
Fuel Mixtures

This paper discusses the development and testing of a full-scale micro-mixing lean-premix injector for hydrogen and syngas fuels that demonstrated ultra-low emissions and stable operation without flashback for high-hydrogen fuels at representative full-scale operating conditions. The injector was fabricated using Macrolamination technology, which is a process by which injectors are manufactured from bonded layers. The injector utilizes sixteen micro-mixing cups for effective and rapid mixing of fuel and air in a compact package. The full scale injector is rated at 1.3 MWth when operating on natural gas at 12.4 bar (180 psi) combustor pressure. The injector operated without flash back on fuel mixtures ranging from 100% natural gas to 100% hydrogen and emissions were shown to be insensitive to operating pressure. Ultra-low NOx emissions of 3 ppm were achieved at a flame temperature of 1750 K (2690 °F) using a fuel mixture containing 50% hydrogen and 50% natural gas by volume with 40% nitrogen dilution added to the fuel stream. NOx emissions of 1.5 ppm were demonstrated at a flame temperature over 1680 K (2564 °F) using the same fuel mixture with only 10% nitrogen dilution, and NOx emissions of 3.5 ppm were demonstrated at a flame temperature of 1730 K (2650 °F) with only 10% carbon dioxide dilution. Finally, using 100% hydrogen with 30% carbon dioxide dilution, 3.6 ppm NOx emissions were demonstrated at a flame temperature over 1600 K (2420 °F). Superior operability was achieved with the injector operating at temperatures below 1470 K (2186 °F) on a fuel mixture containing 87% hydrogen and 13% natural gas. The tests validated the micro-mixing fuel injector technology and the injectors show great promise for use in future gas turbine engines operating on hydrogen, syngas or other fuel mixtures of various compositions.

Characterization of Spray Formed by Diesel-Water Mixture Jet Injected Into an Air Crossflow

2017 ◽  
Author(s):  
Jinkwan Song ◽  
Jong Guen Lee
Keyword(s):  
Diesel Fuel ◽  
Drop Size ◽  
Pure Water ◽  
Fuel Mixture ◽  
Water Mixture ◽  
Fuel Injector ◽  
Spray Characteristics ◽  
Two Fluids ◽  
Mixing Ratios ◽  
Fuel Mixtures

Using a mixture of water and diesel fuel is considered a way to reduce gas emissions including NOx and COx in the gas turbine. This paper presents experimental results on spray characteristics of the water-diesel fuel mixture in an air crossflow. A plain-orifice type injector of 0.508 mm in diameter is employed in the research. Pure water, pure diesel fuel, and water-diesel fuel mixtures with different mixing ratios are used to compare their spray characteristics. In order to observe spray behaviors in different breakup regimes, Weber numbers for water of 30 and 125 are chosen as the operating condition and the corresponding Weber numbers for diesel fuel at the same conditions are 92 and 382, respectively. Momentum flux ratios are 10 and 20. A tee connection and a subsequent static mixer are employed at upstream of fuel injector to mix two liquids. Phase Doppler Particle Analyzer (PDPA) measurement is performed to measure droplet distributions and mean drop size at various mixture ratios, and planar laser induced fluorescence (PLIF) technique with dyeing either diesel or water is used to look into the primary breakup process. PDPA data show that the spray characteristics of water-diesel fuel mixtures such as mean drop size and number density distribution can be predicted from the measured drop size distribution of pure fluids by weighting those quantities by mass fraction of each fluid, indicating that the water and diesel are injected alternately without significant mixing between the two fluids. A short transition of liquid flow from water-to-diesel or diesel-to-water produces small fraction of relatively bigger droplets.

Ignition System Designed to Extend the Plug Life, and the Lean Limit in a Natural Gas Engine

2003 ◽  
Author(s):  
A. K. Chan ◽  
S. H. Waters
Keyword(s):  
Natural Gas ◽  
Engine Performance ◽  
Ignition System ◽  
Gas Engine ◽  
Natural Gas Engine ◽  
Dc System ◽  
Spark Plug ◽  
Long Duration ◽  
Discharge Duration ◽  
Lean Limit

An ignition system that is based on the alternating (AC) rather than the traditional direct (DC) current in the spark plug discharge has been developed at the Caterpillar Technical Center. This system can generate a long duration discharge with controllable power. It is believed that such an ignition system can provide both a leaner operating limit and a longer spark plug life than a traditional DC system due to the long discharge duration and the low discharge power. The AC ignition system has successfully been tested on a Caterpillar single cylinder G3500 natural gas engine to determine the effects on the engine performance, combustion characteristics and emissions. The test results indicate that while the AC ignition system has only a small impact on engine performance (with respect to a traditional DC system), it does extend the lean limit with lower NOx emissions. Evidences also show the potential of reduce spark plug electrode erosions from the low breakdown and sustaining discharge powers from the AC ignition system. This paper summarizes the prototype design and engine demonstration results of the AC ignition system.

scholarly journals Use of the mathematical model of the ignition system to analyze the spark discharge, including the destruction of spark plug electrodes

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Sebastian Różowicz
Keyword(s):  
Mathematical Model ◽  
Experimental Studies ◽  
Fuel Mixture ◽  
Spark Discharge ◽  
Fuel Additives ◽  
Ignition System ◽  
Spark Plug ◽  
The Mathematical Model

Abstract The paper presents the results of analytical and experimental studies concerning the influence of different kinds of fuel additives on the quality of the spark discharge for different configurations of the ignition system. The wear of the spark plug electrode and the value of spark discharge were determined for various impurities and configurations of the air-fuel mixture.

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