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Experimental Study on SI Engine At Different Ignition Timing Using CNG And Gasoline-20% n Butanol Blend

Experimental Study on SI Engine At Different Ignition Timing Using CNG And Gasoline-20% n Butanol Blend

Many researchers have worked on the emission control and performance enhancement of SI engines. M. K Hassan, I. Aris, S. Mahmod, R. Sidek[3] worked on Experimental investigations of performance and exhaust gases, concentration at various ignition and injection timing for high compression engine fuelled with compressed natural gas (CNG) engine. The engine implements central direct injection (DI) method. All injectors are positioned within a certain degrees of spark plug. It is called as CNGDI engine. The results showed that, Low CO concentration occurs at late injection timing and the lowest emission is 0.011% when we applied 300 bTDC of ignition at 3600 CA injection timing. The most influential factor for CO development is ignition timing. Complete combustion occurs at (3000 EOI, 250-280 bTDC) as illustrated in the CO2 and O2 contour. Mardani Ali Sera et al [1] had investigate the effects of density on the performance of a CNG fuelled engine either in dual-fuel, bi-fuel or dedicated forms is lower performance compare to that of gasoline. One significant factor that reduces the CNG engine performance is its low volumetric efficiency due to low density of a CNG fuel. In this research the cooling system and heat exchanger device were installed to 16 L EFI engine to vary the density of CNG fuel. The results showed that the fuel density plays an important effect on the performance of CNG engine and at the same time
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Optimizing the ignition timing of a converted CNG mono gas engine

Optimizing the ignition timing of a converted CNG mono gas engine

experiment conducted by the author. The torque and power trend indicate an arc with a gradient after 29 o BTDC. Thus, it showed that maximum brake torque (MBT) occurs at 29 o BTDC. Kakaee et al., on the other hand, studied on the sensitivity and effect of ignition timing on spark ignition engine. The speed is fixed at 3400 rpm, the ignition timing has been changed in the range of 10 o CA ATDC to 41 o CA BTDC, and the performance characteristics such as power, torque, thermal efficiency, pressure, and heat release are obtained and compared. Their works showed that ignition timings have a significant effect on engine performances.
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Numerical Accuracy of the Kiva4 Code under Different Ignition Timing on the Combustion Characteristics of Gasoline in a Spark Ignition Engine

Numerical Accuracy of the Kiva4 Code under Different Ignition Timing on the Combustion Characteristics of Gasoline in a Spark Ignition Engine

The schematic diagram of the octane rating test BASF octane rating engine used for experiments is as shown in Figure 1. The BASF octane rating engine was made to run for 20 to 30 minutes to warm up. Speed was kept constant at 600 rpm whilst the ignition timing was varied in the range of 4˚ CA BTDC to 18˚ CA BTDC, temperature and pressure values were obtained and compared with Kiva4 and Kiva3vr2. Gasoline BASF octane rating engine is a single cylind- er spark ignition engine as shown below.

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Study and the effects of ignition timing on gasoline engine performance and emissions

Study and the effects of ignition timing on gasoline engine performance and emissions

The engine is mounted on a fully automated test bed and coupled to a Schenck W130 eddy current dynamometer, having load absorbing and motoring capabilities. There is one electric sensor for speed and one for load, with these signals fed to indicators on the control panel and to the controller. Via knobs on the control panel, the operator can set the dynamometer to control speed or load. There is also a capability of setting the ignition timing from a switch on the control panel. The coolant and lube oil circulation is achieved by electrically driven pumps, with the temperature controlled by water fed heat exchangers. Heaters are used to maintain the oil and coolant temperatures during warm up and light load conditions. Figure 1 is the control panel and test engine on dynamometer.
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INFLUENCE OF THE COMPRESSION RATIO AND IGNITION TIMING ON SINJAI ENGINE PERFORMANCE WITH 50% BIOETHANOL- GASOLINE BLENDED FUEL

INFLUENCE OF THE COMPRESSION RATIO AND IGNITION TIMING ON SINJAI ENGINE PERFORMANCE WITH 50% BIOETHANOL- GASOLINE BLENDED FUEL

11, 6. Compression ratios 9,6 and 10, 6 produced similar power in the whole range studied. As the output power is obtained from the product of torque and engine speed, the results shown by Figure 4 are a direct consequence of the ignition timing results shown by Figure-2. In comparison with gasoline fuel, E50 produced a peak brake power 4,58% higher, at 3500 rpm. As same with torque, this increase is due to that high compression ratio increases cylinder pressure so will increasing the work done on the moved piston and consequently increasing of power.
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Effect of Ignition Timing, Equivalence Ratio, and Compression Ratio on the Performance and Emission Characteristics of a Variable Compression Ratio Si Engine using Ethanol-Unleaded Gasoline Blends

Effect of Ignition Timing, Equivalence Ratio, and Compression Ratio on the Performance and Emission Characteristics of a Variable Compression Ratio Si Engine using Ethanol-Unleaded Gasoline Blends

Abstract This paper investigates the effect of ethanol-unleaded gasoline blends (E0,E10,E25,E35,and E65) computer interfaced, four-stroke single cylinder compression ignition engine. The said engine was converted to spark ignition and carburetion to suit ethanol fuel. A suitable provision was provided on the engine to vary the compression ratio thereby making the engine adaptable to operate at lower compression ratios. The tests were performed by varying the ignition timing, equivalence ratio, and compression ratio at a constant speed of 1500 rpm and at wide open throttle (WOT). Effect of ethanol- unleaded gasoline blends and tests variables on engine torque and specific fuel consumption were examined experimentally. The results of this investigation, is believed, to contribute substantially to the knowledge, aimed to ensure a secure future energy.
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Adaptive control of the ignition timing of spark ignition engines utilising the combustion flame light emissions

Adaptive control of the ignition timing of spark ignition engines utilising the combustion flame light emissions

It appears from these considerations that effective combustion in the Spark Ignition engine will be achieved through the normal combustion process where one flame traverses the entire co[r]

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Influence of varying timing angle on performance of an SI engine: An experimental and numerical study

Influence of varying timing angle on performance of an SI engine: An experimental and numerical study

retard, in particular effect of spark retard on cylinder pressure distribution. In cylinder gas temperature and trapped mass under varying spark timing conditions were also calculated . Soylu and Gerpen developed a two zone thermodynamic model to investigate effects of ignition timing, fuel composition and equivalence ratio on burning rate and cylinder pressure for a natural gas engine. Burning rate analysis was carried out to determine flame initiation period and flame propagation period at different engine operating conditions [3]. Others used multi-dimensional reactive flow codes for elaborating modeling of engine flow and combustion processes, which were very sophisticated [4-5]. Accurate prediction of performance parameters and exhaust emissions depends on flow dynamics in the intake manifold, heat transfer and ignition timing. It is feasible to model all these processes with multi- dimensional flow codes coupled with detailed chemical kinetic mechanisms using experimental data. The KIVA-CHEMKIN combination is an example for the detailed modeling of flow and combustion processes in internal combustion engines. However, multi- dimensional modeling of all these processes from the intake manifold to the exhaust manifold needs extensive computation time and very powerful computers. If these multi- dimensional reactive flow codes require large amounts of time, engine designers may not use them. Further, these codes are not still perfect and need some tuning with experimental data, which requires expertise and even more computer time. For this reason, the need for accurate predictions of exhaust emissions pollutants forced the researchers to attempt developing two zone combustion models [6–7]. Eventually, some multi-zone combustion models have appeared, carrying the expected drawbacks of the first attempts, where the detailed analysis of fuel-air distribution permits calculation of the exhaust gas composition with reasonable accuracy [8]. However, this happens under the rising computing time cost when compared to lower zones gasoline combustion models.
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Hydrogen and natural gas comparison in diesel HCCI engines -a review

Hydrogen and natural gas comparison in diesel HCCI engines -a review

Hydrogen addition to the HCCI engine is one of the effective waysto control the ignition timing since hydrogen is able to reduce ignition delay time effectively. Furthermore, hydrogen can be produced from the exhaust gases of the engine itself using a reformer, which is called an“on-board hydrogen producer” [7,32]. As the amount of hydrogen was increased, auto-ignition delay time reduced accordingly while the in-cylinder peak pressure increased, ignition temperature reduced and indicated power increased [1]. The use of hydrogen addition does not involve high cost since it uses a lower-pressure fuel-injection system[30]. Hydrogen addition to a diesel engine will retard the heat release rate and delays the temperature rise. Furthermore, the addition of hydrogen is able to increase the engine efficiency by a significant margin[15,20]. By using a catalytic reforming aid in HCCI,the addition of hydrogen in natural gas HCCI engines helps in decreasing the need for high intake temperatures and also is a means of extending the lower limit of HCCI operations[39]. D. Exhaust Gas Recirculation (EGR)
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Prediction of Performance a Direct Injection Engine Fueled with Natural gas–Hydrogen Blends

Prediction of Performance a Direct Injection Engine Fueled with Natural gas–Hydrogen Blends

volume. The result shows that the percentage of hydrogen in the CNG increases the burning velocity of CNG and reduces the optimal ignition timing to obtain the maximum peak pressure of an engine running with a blend of hydrogen and CNG. With hydrogen addition to natural gas, the peak heat release rates increase. For 20% hydrogen, the maximum values at crank angles (CAs) for in-cylinder temperature and heat release rate are achieved at 6° CA, and the maximum temperature is approximately 150 K. also it can be seen that torque and power was increased with adding hydrogen to natural gas and it is about 3%. Port injection gasoline is converted into direct injection by CNG fuel in this engine.
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Research on control of ignition and THC formation in CNG engines by the application of gas jet direct ignition technique

Research on control of ignition and THC formation in CNG engines by the application of gas jet direct ignition technique

The combustibility using this method relies on local fuel-air mixture concentration near the ignition position. The gas-jet ignition method employs late injection timing technique which is very near to the ignition timing. The optimal injection timing is when the injected fuel just reaches the ignition point with low jet velocity to ensure ignitability, while at the same time creating enough combustible mixture to support flame core development. The ignitability of mixture using this method has been studied by several authors [60, 71, 75, 76]. According to Kidoguchi et al. [60] the ignitability of gas-jet ignition is ensured if the spray velocity hitting the ignition point is less than 16 m/s and the local mixture surrounding the spark position is near stoichiometric. Spray velocity higher than this value or the rich fuel distribution locally near the ignition point, would result in flame quenches or misfires.
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Numerical Study on the Hydrogen Fueled SI Engine Combustion Optimization through a Combined Operation of DI and PFI Strategies

Numerical Study on the Hydrogen Fueled SI Engine Combustion Optimization through a Combined Operation of DI and PFI Strategies

Finally, the CFD code has been intensively validated against experimental engine data which provided a re- markable agreement in terms of the in-cylinder pressure history evaluation as seen in Figure 10. Three tested cases of the proposed hydrogen supply (PFI + DI) technique have been selected to evaluate the uncertainty of the achieved data from our CFD code. These cases are introduced in the legend to Figure 10 which includes the total air-fuel equivalence ratio of 0.33, 0.63, and 0.85 to represent low, moderate, and high load condition, re- spectively. The selected percentages of direct injection ratio and the ignition timing are optimized in order to produce maximum cycle efficiency and maximum brake torque conditioning. As seen in Figure 10, the com- parison shows a remarkable coincidence between accom- plished numerical and experimental data. There is a pronounced difference between the numerical and ex- perimental data for the in-cylinder pressure peak values at moderate and high load conditions. This disagreement or inconsistency is caused by the kinetic model of an early one-step global reaction mechanism. This model has been activated instead of that based on the ele- mentary reactions which offer the best accuracy and re- liability. However, one-step mechanism omits impor- tant chain initiating or chain branching processes at the ignition and combustion process. But we consider this method in viewing the fact that the computational time is
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Numerical Study of a Spark Assisted Compression Ignition (SACI) Engine Using the One-Dimensional Turbulence (ODT) Model.

Numerical Study of a Spark Assisted Compression Ignition (SACI) Engine Using the One-Dimensional Turbulence (ODT) Model.

6 kernel growth (EKG) stage. However, due to limitations in diagnostic methods, the effect of the spark plasma in this stage could not be measured. This limitation was overcome in the study conducted by Natarajan and Reuss, [9], and the first conclusion of the previous study was confirmed. However, it was found that the spark ignition system did not affect the EKG cyclic variations, but the charge composition distribution did. Pastor et al. [10], combined direct visual diagnostic methods and spectroscopic analysis of natural radiation, with analysis of Rate of Heat Release, to validate the works of Reuss [8,9]. The spectral analysis of the combustion reaction radicals was used to study the progress of the combustion process and identify the transition of the SACI stages. A similar research was conducted by Benajes et al. [11], for a gasoline partially premixed spark assisted compression ignition engine at low load to better observe the combustion process. It was found that, apart from spark assistance and ignition timing, the fuel injection timing and duration had an important role in improving combustion stability, cyclic stability and combustion phase duration. The author continued this work in [12] to show the effect on emissions due to single and double direct fuel injection strategies, and by varying the fuel fraction in the double injection case. It was concluded that air/fuel mixture distribution was improved using double injection strategy and increased the fuel energy conversion efficiency.
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Laser Ignition System over Spark Ignition

Laser Ignition System over Spark Ignition

To provide appropriate ignition timing for combustion, igniters is in communication with an electronic control module (ECM) via power supply and fibre optics. Based on various input received by ECM like engine speed, engine load, emissions production or output, engine temperature, engine fuelling, and boost pressure, ECM may selectively direct a high-energy light beam from a laser energy generator to each igniter via fibre optics cable.ECM include components like memory, a secondary storage device, and a CPU.A battery of 12v to 24v gives power to either ECM or Laser generator or both. The ECM controls the laser energy generator to direct one or multiple laser beams into the combustion chamber. In the laser igniters, multi- photon ionization of few gas molecules takes place which releases electrons that readily absorb more photons via the inverse bremsstrahlung process to increase their kinetic energy. Electrons liberated by this means collide with other molecules and ionize them, leading to an electron avalanche, and breakdown of the gas. Multiphoton absorption processes are usually essential for the initial stage of breakdown because the available photon energy at visible and near IR wavelengths is much smaller than the ionization energy. For very short pulse duration (few picoseconds) the multiphoton processes alone must provide breakdown, since there is insufficient time for electron-molecule collision to occur. Thus, this avalanche of electrons and resultant ions collide with each other producing immense heat hence creating plasma which is sufficiently strong to ignite the fuel. The wavelength of laser depends upon the absorption properties of the laser and the minimum energy required depends upon the number of photons required for producing the electron avalanche.
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Effect of Injection Timing and cold EGR on Performance and Emission Characteristics of a Stationary Single Cylinder DI Diesel Engine Fueled with n Butanol/Diesel Blends

Effect of Injection Timing and cold EGR on Performance and Emission Characteristics of a Stationary Single Cylinder DI Diesel Engine Fueled with n Butanol/Diesel Blends

the basic method to control ignition timing and the burn rate of HCCI combustion. Brijesh et al, (2015)[10] optimized various parameters like injection parameters, compression ratio and amount of ultra-cooled exhaust gas recirculation has been done for a variable compression ratio engine, to achieve low-temperature combustion, with an objective to reduce both NOx and soot simultaneously. Taguchi analysis showed CR and EGR were dominant factors compared to the injection parameters. Result indicated a simultaneous reduction in NOx (98%) and PM (60%) was achieved with an increase in BTE (5%) by combining the moderate rate of ultra-cooled EGR with retarded injection timing and moderate CR. Huang et al, (2016)[11] studied the particle emissions under different EGR ratios on a diesel engine fueled by blends of diesel/gasoline/n-butanol. The in-cylinder pressure peak decreases and heat release is delayed for the combustion of each fuel as the EGR ratio increases. As the EGR ratio increased, the total particle number concentrations for the four blends decreased at first, and then increased. As the EGR ratio increased, the soot emissions during the combustion of four fuels also increased, and the ratios of the number concentrations of the sub-25 nm particles to the total particle number concentrations decreased for all the investigated fuels. Nwafor, (2004)[12] investigated the effect of injection timing on emission characteristics of diesel engine running on biofuel. The test results show that the lowest carbon monoxide (CO) and CO, emissions were obtained with the advanced injection unit. The hydrocarbon (HC) emissions of the engine running on vegetable oil fuels were significantly reduced compared to the test results on baseline diesel fuel. The advanced injection system showed a slight increase in fuel consumption
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Minimizing engine emissions using state feedback control with LQR and artificial intelligence fuel estimator

Minimizing engine emissions using state feedback control with LQR and artificial intelligence fuel estimator

Engine combustion performance can be affected by engine operating parameters, such as fuel to air ratio, ignition timing, and the valve opening and closing event [13], hence emission control can be achieved by system identification of an inverse engine combustion process and optimisation using closed-loop control algorithms. To achieve this, various sensors are fitted onto the engine in order to monitor the combustion process. They are able to collect exhaust gas information, including the amount of carbon dioxide (CO2), oxygen (O2), carbon monoxide (CO) and nitric oxide (NOx), as well as the condition of exhaust gas including exhaust gas temperature and pressure [7]. The Engine Control Unit (E.C.U.) can use such information to calculate the optimal engine operating parameters to control the emissions while keeping the engine in the best possible performance. The exhaust substance contains CO and NO, which are considered as pollutants and the maximum amount allowed is regulated by law.
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Studies in engine test bed automation

Studies in engine test bed automation

I n it ia l studies carried out by Draper and L i. ( l l ) which were concerned with the optimisation of ignition timing and air/fuel ratio have demonstrated the feasab ility of such an operation using analog computing technioues. These and other .investigators (12) failed to indicate two salien t features of the combustion process which are of direct consequence to optimisation. F irs tly , combustion is a discrete process. Any changes irr operating conditions w ill not take effect u ntil a fte r the combustion cycle is in itia te d , and the results of these changes w ill not manifest themselves u n til after the combustion cycle is complete. Secondly the process is irregular, and any
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Optimization of the parameters of Alcohol Fuels for best Performance and Exhaust of Copper Coated Spark Ignition Engine

Optimization of the parameters of Alcohol Fuels for best Performance and Exhaust of Copper Coated Spark Ignition Engine

Abstract: The main objective of this work to improve the engine performance of gasoline - Methanol blends in a variable compression ratio engine by using optimized engine parameters. In the present work, variable compression ratio spark ignition engine was designed to run with pure gasoline, and gasoline blended with 20% methanol (M20) by volume. Experiments are conducted at different ignition timings 25 0, 26 0 ,27 0 ,28 0 , and 29 0 bTDC for conventional engine and for a copper coated piston and cylinder head of the engine. From the comparative evaluation the experimental results for the different ignition timing, it is revealed that there is an influence of the copper coated engine and methanol blend (M20). Optimization is carried out for efficiency and emission using response surface methodology with NSGA II as optimization tool and Non Parametric Regression for response surface generation. From the analysis, it was found that for 26.7 0 bTDC ignition timing, the copper coated engine blended with methanol (M20) has given best performance in terms of volumetric efficiency of 85 %, thermal efficiency of 31.238% and exhaust temperature of 339.2 0 C. It is finally observed from the mathematical models and experimental data that pure gasoline and methanol blends have maximum efficiency and minimum emissions at optimized engine parameters.
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Combined effect of ignition and injection timing along with hydrogen enrichment to natural gas in a direct injection engine on performance and exhaust emission

Combined effect of ignition and injection timing along with hydrogen enrichment to natural gas in a direct injection engine on performance and exhaust emission

To improve the engine performance and reduce emissions, factors such as changing ignition and injection timing along with converting of port injection system to direct injection in SI(spark-ignited) engines and hydrogen enrichment to CNG fuel at WOT conditions have a great importance. In this work, which was investigated experimentally (for CNG engine) and theoretically (for combustion Eddy Break-Up model and turbulence model is used) in a single- cylinder four-stroke SI engine at various engine speeds (2000-6000 rpm in 1000 rpm intervals), injection timing (130-210 crank angle(CA) in 50 CA intervals), ignition timing (19-28 CA in 2 degree intervals), 20 bar injection pressure and five hydrogen volume fraction 0% to 50% in the blend of HCNG. The results showed that fuel conversion efficiency, torque and power output were increased, while duration of heat release rate was shortened and found to be advanced. NOx emission was increased with the increase of hydrogen addition in the blend and the lowest NOx was obtained at the lowest speed and retarded ignition timing, hence 19° before top dead center.
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ANN Analysis of Injection Timing on Performance Characteristics of Compression Ignition Engines Running on the Blends of Tropical Almond Based Biodiesel

ANN Analysis of Injection Timing on Performance Characteristics of Compression Ignition Engines Running on the Blends of Tropical Almond Based Biodiesel

For a diesel engine, fuel injection timing is a major parameter that affects combustion and exhaust emissions. Proper ignition delay is necessary for ensuring proper pressure rise and peak pressure and hence maximum thermal efficiency, which in turn depends on the type of fuel also. [19] conducted experiments in a dual fuel CI (Compression ignition) engine to study the effect of injection timings on the exhaust emissions. They used ethanol blends with diesel and conducted experiments at five different injection timings. They observed that NOx and CO2 emissions increased and HC and CO emissions reduced for advanced injection timing. [20] carried out experiments on a single cylinder diesel engine with natural gas as the fuel. On advancing injection timing by 5.5˚ the engine showed erratic performance and when it was reduced to 3.5˚ he observed a smooth performance especially at low load conditions. Fuel consumption was slightly increased whereas CO and CO2 emissions were reduced. Similarly, second generation biofuels which tropical almond biodiesel belongs have been largely applied in operating internal combustion engines. The following works show how fuels derived from plant sources have been used to run CI engines. Ashok et al., [21] applied orange peel oil of 20% to evaluate performance and emission characteristics of a CRDi engine. The evaluation showed improved performance
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