Charge Stratification in a Spark Ignition Engine

1992 ◽  
Vol 206 (1) ◽  
pp. 59-64 ◽  
Author(s):  
R K Green ◽  
C C Zavier
Keyword(s):  
Engine Performance ◽  
Fuel Mixture ◽  
Spark Ignition Engine ◽  
Normal Operation ◽  
Stratified Charge ◽  
Lean Mixture ◽  
Reciprocating Engine ◽  
Injection Process ◽  
Spark Plug ◽  
Hydrocarbon Emission

The effect of charge stratification on lean mixture combustion in a Ricardo E6 single-cylinder four-stroke reciprocating engine has been investigated. To do this, a commercially available spark plug was modified so that small amounts of pure methane gas could be injected, via the spark electrode, into a lean mixture within the combustion chamber prior to ignition. The effect on engine performance of variations in the methane injection process were analysed. The research has led to the following conclusions: 1. The lean limit of a homogeneous air-fuel mixture is extended by this relatively simple charge stratification process. 2. The effectiveness of charge stratification is most noticeable at lean air-fuel ratios in terms of improved brake specific fuel consumption. 3. Unburnt hydrocarbon emission levels are higher with the stratified charge process when compared to normal homogeneous mixture operation. 4. Carbon monoxide levels with stratified charge combustion are almost the same or a little lower than normal operation at the leanest air-fuel ratios.

The Lean Mixture Operational Limits of a Spark Ignition Engine When Operated on Fuel Mixtures

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Hailin Li ◽  
Ghazi A. Karim ◽  
A. Sohrabi
Keyword(s):  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Si Engine ◽  
Lean Mixture ◽  
Si Engines ◽  
Unstable Combustion ◽  
Fuel Mixtures ◽  
Traditional Approaches ◽  
Combustion Processes

The operation of spark ignition (SI) engines on lean mixtures is attractive, in principle, since it can provide improved fuel economy, reduced tendency to knock, and extremely low NOx emissions. However, the associated flame propagation rates become degraded significantly and drop sharply as the operating mixture is made increasingly leaner. Consequently, there exist distinct operational lean mixture limits beyond which satisfactory engine performance cannot be maintained due to the resulting prolonged and unstable combustion processes. This paper presents experimental data obtained in a single cylinder, variable compression ratio, SI engine when operated in turn on methane, hydrogen, carbon monoxide, gasoline, iso-octane, and some of their binary mixtures. A quantitative approach for determining the operational limits of SI engines is proposed. The lean limits thus derived are compared and validated against the corresponding experimental results obtained using more traditional approaches. On this basis, the dependence of the values of the lean mixture operational limits on the composition of the fuel mixtures is investigated and discussed. The operational limit for throttled operation with methane as the fuel is also established.

Cogeneration—the development and implementation of a cogeneration system for a chemical plant, using a reciprocating heavy fuel oil engine with a supplementary fired boiler

2003 ◽  
Vol 217 (5) ◽  
pp. 493-503 ◽  
Author(s):  
M Coelho ◽  
F Nash ◽  
D Linsell ◽  
J. P. Barciela
Keyword(s):  
Natural Gas ◽  
Chemical Plant ◽  
Spark Ignition Engine ◽  
Fuel Oil ◽  
Normal Operation ◽  
Saturated Steam ◽  
Exhaust Gas ◽  
Heavy Fuel Oil ◽  
Reciprocating Engine ◽  
Cogeneration System

The contribution of cogeneration plants to a reduction in primary energy consumption will be important not only in lowering emissions to the atmosphere but also in cutting production costs by increasing the overall efficiency of fuel conversion to the electricity and heat used by process industries. This paper demonstrates the importance of the interactions of the utility needs of a process with the development and design of a cogeneration system to maximize fuel efficiency and achieve environmental compliance for a chemical plant. The cogeneration system in this project is based on a diesel cycle engine burning heavy fuel oil (HFO), driving an alternator and with an exhaust gas heat recovery boiler supplementary fired with either HFO or natural gas. The normal operation of the cogeneration plant is with the engine running at 95–100 per cent maximum continuous rating (MCR) with the supplementary firing of the boiler modulating to meet the process requirements for saturated steam at 10 barg. In addition to recovering waste heat from the engine exhaust gas (EEG), supplementary firing using the excess oxygen in the exhaust gas enables the process steam required by the plant to be produced without the loss of energy involved in heating combustion air. At the same time the reduced volume of oxygen available to the flame reduces peak temperature and NOx emissions, this being further enhanced by the phased combustion design of the burner. The technology demonstrated in this application is generally as used in gas turbine cogeneration cycles burning natural gas. The use of HFO in this instance necessitated the use of a reciprocating engine driven generator and the development of supplementary firing of the exhaust gases. The successful development of the technology enables this reciprocating engine based cogeneration system to be scaled up or, possibly more importantly, down utilizing HFO, natural gas or renewable derived liquid or gaseous fuels. Its implementation using spark ignition engine generators retrofitted to economic boilers may be one way general industry in the United Kingdom might meet its climate change levy (CCL) targets for energy reduction and help approach the government's carbon reduction requirements.

Characteristics of New Ignition Systems to Improve Engine Performance

1967 ◽  
Vol 182 (1) ◽  
pp. 15-24 ◽  
Author(s):  
By R. C. Teasel ◽  
R. D. Miller
Keyword(s):  
United States ◽  
Engine Performance ◽  
Spark Ignition ◽  
Spark Discharge ◽  
Spark Ignition Engine ◽  
Development Effort ◽  
Engine Operation ◽  
Discharge Characteristics ◽  
Ignition System ◽  
Spark Plug

The increasing use of spark ignition engines throughout the world has confronted the engine designer with new problems such as air pollution, world-wide temperature extremes, as well as legislative, economic, and human considerations. To meet these situations and improve the competitive position of the spark ignition engine requires considerable research and development effort. This paper reports on work conducted by Champion Spark Plug Company in attempting to evaluate the potential contribution that ignition system and spark plug designs can make towards improving spark ignition engine operation. Almost all the work reported here covers investigations in current large displacement United States passenger car engines. The three main characteristics of the overall ignition systems that are investigated are (1) the available output voltage characteristics of the ignition systems; (2) the effect of the ignition system spark discharge characteristics on engine performance; and (3) the effect of several spark plug design features on engine performance. This investigation shows that the inter-relationship of the ignition system spark discharge characteristics and the spark plug design requires that the overall evaluation must consider the dependence of both items. It also suggests that significant improvements can result in other United States and European engines, through the careful evaluation of ignition system and spark plug designs. The results of this work indicate that a fast rise time, short arc duration system results in reduced spark plug gap growth and better resistance to spark plug fouling. However, the arc duration must not be shorter than a minimum value, or a loss in engine performance may result. High output systems are desirable as they provide a higher voltage reserve to provide longer spark plug life, but the higher voltages that occur with the larger spark plug gaps can stress other ignition system components. The spark plug designs which incorporate a projection of the spark plug gap result in better performance in the engines tested, and possibly even reduce exhaust emissions. Certainly other features which engine manufacturers must consider, which are not discussed in detail here, are costs, durability, and maintenance of the new systems. At least one other important related problem is that of interference.

scholarly journals Analysis of Air Flow, Air and Fuel Induction for Internal Combustion Engine

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Mohd Fitri Arshad ◽  
◽  
Muhammad Faris Ahmad ◽  
Amir Khalid ◽  
Izuan Amin Ishak ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Flow Behavior ◽  
Combustion Process ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Internal Combustion ◽  
Spark Ignition Engine ◽  
Rotating Flow

In an internal combustion engine, performance, efficiency and emission formation depends on the formation of air-fuel mixture inside the engine cylinder. The fluid flow dynamics plays an important role for air-fuel mixture preparation to obtain the better engine combustion, performance and efficiency. This review article discuss the rotating flow (swirl and tumble) in premixed spark-ignition engine and its effect on turbulence generation and flame propagation. Rotating flow can substantially increase turbulence intensity for the duration of the combustion period. This review paper discusses the in-cylinder swirl and tumble flow that affects air induction during the combustion process in internal combustion engine. Alternatively, this study using computer simulation (Computational Fluid Dynamic, CFD) which offer the opportunity to carry out repetitive parameter studies. An integration-type flowmeter (IFM) also has been used which consists of ultrasonic flowmeter, that integrates the flowrate during the intake process, gives accurate measurements regardless of sampling time and frequency. Research parameter in this study was swirl and tumble that represents the fluid flow behavior occurred inside combustion chamber. Fuel injection and air mass also were the important parameters that have been discussed about in air induction process. The results obtain from the numerical analysis can be employed to examine the homogeneity of air-fuel mixture structure for better combustion process and engine performance.

Effect of Injection Timing on Fuel-Air Mixing and Combustion in a Direct Injection Stratified Charge SI Engine

2007 ◽  
Author(s):  
T. Anand Kumar ◽  
J. M. Mallikarjuna ◽  
V. Ganesan
Keyword(s):  
Numerical Study ◽  
Direct Injection ◽  
Combustion Characteristics ◽  
Spark Ignition Engine ◽  
Injection Timing ◽  
Flame Surface ◽  
Si Engine ◽  
Stratified Charge ◽  
Spark Plug ◽  
Air Mixing

This paper describes a numerical study on fuel-air mixing and combustion in a direct injection stratified charge spark ignition engine. The in-cylinder flow, fuel-air mixing and combustion characteristics are investigated in a single cylinder, four-valve, four stoke, direct injection SI engine with pent-roof head and reverse tumble ports. The engine combustion chamber had the side mounted injector and spark plug at the center of pent-roof. Wall guided fuel-air mixing scheme has been adopted. The pre processor code Es-ice, used for dynamic grid generation preparation including description of piston and valve motion. Commercial computational fluid dynamics code Star-CD is used for solving governing equations and post processing of results. Combustion in the present study is simulated using Extended Coherent Flame Model-3z (ECFM-3Z). This model is based on a flame surface density transport equation that can describe inhomogeneous turbulent premixed combustion. In the present study, engine simulations has been carried out from 370 CAD before TDC and upto 90 CAD aTDC. The process includes the closing of the exhaust valves, the whole intake stroke, injection, combustion, and part of expansion. Three different injection timings are simulated viz. 55, 60 and 65 CAD bTDC. For validation of the code predicted results are compared with experimental results available in the literature. It is observed that, injection timing has an important role in mixture preparation and distribution around the spark plug. Hence, for the better combustion characteristics start of injection timing should be optimized.

scholarly journals Improvement of Fusel Oil Features and Effect of Its Use in Different Compression Ratios for an SI Engine on Performance and Emission

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1824 ◽  
Author(s):  
Süleyman Şimşek ◽  
Hasan Saygın ◽  
Bülent Özdalyan
Keyword(s):  
Compression Ratio ◽  
Engine Performance ◽  
Spark Ignition Engine ◽  
Test Results ◽  
Fuel Blend ◽  
Fusel Oil ◽  
Performance And Emission ◽  
Fuel Blends ◽  
Spark Plug ◽  
Hc Emissions

In this study, the effects of the use of improved fusel oil on engine performance and on exhaust emissions in a spark-ignition engine were investigated experimentally in consideration of the water, gum, and moisture content at high compression ratios according to TS EN 228 standards. In the study, a four-stroke, single-cylinder, air-cooled, spark plug ignition engine with an 8/1 compression ratio was used at three different compression ratios (8/1, 8.5/1, 9.12/1). Experiments were performed for six different ratios of fuel blends (F0, F10, F20, F30, F40, and F50) at a constant speed and different loads. The data obtained from the experiments were compared with the original operating parameters of the engine while using gasoline. According to the test results, the optimal engine performance was at a 9.12/1 compression ratio and with a F30 fuel blend. With the increase from an 8/1 to 9.12/1 compression ratio for the F30 fuel blend, the overall efficiency increased by 6.91%, and the specific fuel consumption decreased by 2.35%. The effect of the optimum fusel blend on the emissions was also examined and CO emissions were reduced by 36.82%, HC emissions were reduced by 23.07%, and NOx emissions were reduced by 15.42%, while CO2 emissions were increased by 13.88%.

Spark-ignition engine performance with ‘Powergas’ fuel (mixture of CO/H2): A comparison with gasoline and natural gas

Fuel ◽  
2006 ◽  
Vol 85 (12-13) ◽  
pp. 1605-1612 ◽  
Author(s):  
N MUSTAFI ◽  
Y MIRAGLIA ◽  
R RAINE ◽  
P BANSAL ◽  
S ELDER
Keyword(s):  
Natural Gas ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Spark Ignition ◽  
Spark Ignition Engine

An Insight into Combustion Process in a Spark Ignition Engine Using Three Dimensional Modeling

2011 ◽  
Vol 110-116 ◽  
pp. 3016-3024
Author(s):  
Moslem Yousefi ◽  
F. Ommi ◽  
Mehdi Farajpour
Keyword(s):  
Combustion Process ◽  
Three Dimensional ◽  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Experimental Result ◽  
Maximum Temperature ◽  
Three Dimensional Model ◽  
Three Dimensional Modeling ◽  
Spark Plug

In this paper a three dimensional model of a spark ignition engine is presented using KIVA-3V code to investigate the combustion process of engine and gain a better understanding of what happens during this stage. The Whole engine cycle is simulated and the validity of the model is examined by experimental result of in-cylinder bulk pressure. the effect of ignition timing, spark plug location on the engine performance and pollutants of this engine has been investigated .The numerical results show that Relocating the spark plug near to the exhaust valves in order of taking advantage of higher temperature does not have the desired results. Using lean excessive air results in decreasing advancing the ignition results in an increase in the maximum bulk pressure and power of engine. Due to increase in maximum temperature of the combustion chamber the amount of NOx rises, too.

Experimental Investigation of a Four Stroke Spark Ignition Engine Operated with Naphtha or Gasoline Blended LPG

2016 ◽  
Vol 841 ◽  
pp. 272-277 ◽  
Author(s):  
Samer M. Abdulhaleem ◽  
Hind A. Mohammed
Keyword(s):  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Energy Equivalent ◽  
Engine Efficiency ◽  
Unburned Hydrocarbon ◽  
Liquid Petroleum Gas ◽  
Hydrocarbon Emission ◽  
Blended Fuel ◽  
Energy Replacement

In this study experimental work has been conducted using liquid petroleum gas (LPG) as blended fuel with naphtha or gasoline in a spark ignition engine in order to reduce pollutants emissions and to improve engine performance. The fuel blended is done on energy replacement basis which means that the amount of LPG added has an amount of energy equivalent to the energy of naphtha or gasoline removed. The results showed that the LPG blended improve engine efficiency until about 20% blended ratio and reduces CO, CO2, and NOx but causes an increase in unburned hydrocarbon emission. The test carried out at constant compression ratio (6:1), under different load with variety percentage of LPG energy blending ratio of (10-25) %.

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