Ethanol Gasoline Mixtures Research Articles

Modeling and Parameter Identification of Spark Plug Deposit Formation Mechanism for Different Fuel/Lubricant Combination

Abstract The identification of model parameters is complex and requires many approximations and laboratory investigations. Here, a novel approach to identifying these parameters is proposed, which uses experimental data, and a parameter estimation method to minimize a cost function made up of errors between the predicted and experimental deposit thickness. Parameters are determined for various ethanol–gasoline mixtures and lubricants. Simultaneously, the thermal and electrical properties of deposits are studied, and this information, coupled with the identified parameters, is utilized to infer potential deposit formation sources, mechanisms, and other elements that will influence the characteristics of the spark plug. It is found that the deposit formation model along with the identified parameters has the potential to reliably estimate the deposit growth with time as good correlations have been observed between measured and predicted spark plug deposit mass for all fuels and lubricants. The thermal and electrical conductivity of the spark plug deposit increases with a high ethanol fraction and high viscous oil, which results in increased chances of side sparking.

Exploring the effect of coatings and ethanol-blended fuels on emission reduction: Experimental study and neural network approach

This article highlights the detrimental impact of vehicle emissions on the environment and explores using new technologies and alternative fuels to reduce this impact. One such technology is thermal barrier-coated pistons, which decrease heat absorption by the engine and reduce emissions. Ethanol is also explored as a cleaner-burning alternative to traditional gasoline. Experimental studies were conducted to investigate the effects of coating and fuel blends on engine performance and emissions. Artificial neural networks were also used to predict emissions. Results showed that both the coating and ethanol-gasoline mixtures led to a decrease in emissions. The experimental study revealed that the coating caused HC emissions to decrease by 8% and NOx emissions to rise by 6%. In the case of using a 10% ethanol gasoline mixture in the coated engine, a 19% decrease in HC emissions and a 13% decrease in NOx emissions in 20% ethanol gasoline mixtures were determined compared to the uncoated piston. The study also examined thermal analysis results and compared the accuracy of different artificial neural network algorithms in predicting emissions. The development of alternative fuels and technologies is essential to reduce the environmental impact of vehicle emissions for a sustainable future.

Influences of Compression Ratio on Performance of Single Cylinder Otto Engine Using E50 Fuel

Ethanol mixed with a primary fuel is a promising alternative fuel. To increase performance, an optimal compression ratio must be set. The compression ratio is the ratio of the maximum volume divided by the minimum volume. Ethanol-gasoline mixtures have high octane and can be used in high-compression engines. This research aims to identify how changes in compression ratio can affect various aspects of engine performance, including torque, power, fuel efficiency, and thermal efficiency. This study is expected to reveal new insights that can aid in optimizing engine performance and developing a more comprehensive understanding of the characteristics of the E50 fuel within the context of Otto engine usage. A single-cylinder Otto engine was used for testing. Compression ratios of 9.3:1, 10.3:1, and 11.3:1 were tested. The results showed that the compression ratio of 9.3:1 produces a peak torque of 7.17 N∙m, peak power of 3.36 kW, lowest BSFC of 0.275 kg/kWh, and highest BTE of 37.49%. A compression ratio of 10.3:1 produces a peak torque of 7.21 N∙m, peak power of 3.57 N∙m, lowest BSFC of 0.281 kg/kWh, and highest BTE of 39.46%. A compression ratio of 11.3:1 produces a peak torque of 7.73 N∙m, peak power of 3.81 kW, lowest BSFC of 0.275 kg/kWh, and highest BTE of 40.36%. Compared with pertalite, E50 reduces torque by 9.25%, power by 9.93%, BSFC by 3.66%, and BTE by 8.76% at all compression ratios.

Influence of high compression ratio on the performance of ethanol-gasoline fuelled lean burn spark ignition engine at part throttle condition

As a viable solution to meet rising energy costs and reduce greenhouse gases, alcohol fuels are considered the most promising renewable fuel and ethanol is a potential fuel for spark ignition engines. In the present study, experiments were conducted on a spark ignition engine modified from a diesel engine that uses an ethanol-gasoline mixture as fuel under lean operating conditions. The engine was operated at 1500 rpm at a high compression ratio of 10.5:1. The different proportions of ethanol namely 5 %, 10 %, 20 %, and 30 % with gasoline, were studied and compared. The throttle was set to 25 % to operate the engine at various equivalence ratios to study the performance and emissions. Experimental outcomes reveal that 10 % ethanol with gasoline enhances the brake thermal efficiency and brake power by 7 % and 4.5 % respectively, due to an enhanced compression ratio. Further, the gasoline lean limit is also extended from 0.74 to 0.70 equivalence ratios. In addition, ethanol blending with gasoline enhances the combustion characteristics and heat release rates. The influence of ethanol greatly decreases cycle-by-cycle variations and hydrocarbon emissions. Adopting a high compression ratio and lean-burn operation can effectively improve performance and decrease emissions in an ethanol-gasoline-fuelled spark ignition engine.

Simulation analysis of cycle skipping strategy in SI engine fueled with ethanol gasoline mixture

Researches are carried out with different methods to reduce the emissions emitted by conventional fuel engines. In addition to using alternative fuels, especially ethanol, in gasoline engines, fuel injection, and combustion controls are applied in various strategies. In this study, the effects of various cycle skipping strategies on emissions were analyzed through a numerical model of a single-cylinder naturally aspirated spark ignition (SI) engine. The validated model was fueled with an ethanol gasoline blend with 30% ethanol content. The model engine was operated at partial load and 1500 rpm constant engine speed under Normal (N), 1N1S, 2N1S and 3N1S cycle skip strategies. NOx emission increased with all strategies due to increased in-cylinder temperature with more fuel depletion in ignition cycles. The BSFC decreased by 9.93%, 13.67% and 5.93% in the 1N1S, 2N1S and 3N1S cycle skipping strategies, respectively. CO and HC emissions decreased with all cycle skipping strategies compared to the normal cycle.

Energy Effect of the Degree of Hydration of Ethanol and the Air Excess Coefficient (a) on the Use of Ethanol-Gasoline Mixtures in Spark Ignition Engines

The objective of this study was to evaluate energetically the effect of hydration degree and mixture type (rich mixture α = 0,85 and lean mixture α = 0,15) on the use of ethanol and gasoline mixtures in spark ignition engines. The experiments were carried out in the Propulsion Laboratory of the Faculty of Engineering Sciences of Agrarian University of Havana (AUH). The JACTO model engine used has an effective power of 1,2 kW, speed 580 rpm, combustion chamber volume 34 cm 3 . Before combustion, the degree of ethanol hydration was determined (80 %; 85 %; 90 %; 95 %). Taking into account the influence of the percentage of purity of ethanol and air excess coefficient (α), when using combustible mixtures, analyses were carried out on the following parameters: air-fuel ratio (r a/f ) and fuel-air ratio (r f/a ); internal energy of combustion products (U z ); the number of moles of raw materials in the mixture for gasoline engines (M 1 ) and the number of moles of products during combustion (M 2 ). Based on the experimental work performed and the energy analysis of the combustion process, it was shown that the mixture of gasoline E-10-EH-80 % received more air and fuel than ratio necessary to achieve combustion, reaching 11,781 kg (air)/kg (fuel) for α = 0,85 and 15,309 kg (air)/kg (fuel) for α = 1,15. This is due to the fact that this is a mixture with increased moisture, because it contains more oxygen atoms, which impoverishes the mixture, and guarantees the best quality in the combustion process. But rich mixtures (α = 0,85) were the most energy efficient, which is associated with an increase in the octane number, that is, the antiknock ability of the fuel mixture used, which improves the quality of combustion, although it reduces the energy output during an explosion (detonation).

Effect of ethanol on auto-ignition characteristics and laminar burning velocity of gasoline under elevated temperature and pressure

Gasoline and its surrogate fuels have developed rapidly in recent years, and the study of the theory of multi-fuel mixed combustion is vital to the improvement of power machines. On the basis of the important role of ethanol-gasoline mixtures in oxygenated alternative fuels, Cai and Pitsch’ s mechanism was selected for a numerical study to research the important role of ethanol with respect to combustion of gasoline from a chemical kinetic perspective. It is found that the addition of ethanol accelerates the LBV and shortens the IDTs of gasoline, and the LBV of ethanol-gasoline mixtures goes up as both the initial temperature and the ethanol ratio rise, while the LBV of ethanol-gasoline mixtures declines as the initial pressure increases. The IDTs of ethanol-gasoline mixtures tend to decrease as the initial temperature, ethanol ratio and initial pressure increase. The addition of ethanol increases the production of the intermediates CH3, HCO and CH2O, and the reactive radicals in the system increase with the addition of ethanol. In addition, the addition of ethanol can lead to an earlier surge of OH groups. This study is not only helpful for the design of ethanol-gasoline power engines, but also promotes the development of alternative fuels.

Experimental Investigation of Spark Ignition Engine Performance Fuelled with various Pomegranate Ethanol-Gasoline Mixtures

Experimental Investigation of Spark Ignition Engine Performance Fuelled with various Pomegranate Ethanol-Gasoline Mixtures

Study on the Effects of Ethanol-gasoline Octane Number on Anti-knock Performance in Direct-injection Gasoline Engine

ABSTRACT The high strength technology for gasoline engines improves the thermal efficiency, while at the same time, increasing the knocking tendency. To improve the anti-knock performance of gasoline engines, blending mixture of fuels are needed with higher requirements. In this paper, ethanol/TRF fuel was selected as the gasoline substitute and the effects of fuel octane number and ethanol content on anti-knock performance were simulated in a three-dimensional engine model. The results show that when knock occurs, the knock amplitude is larger at the intake port and the knock onset is earlier at the exhaust port. With the enhancement of anti-knock performance, abnormal combustion such as spontaneous ignition of the end-gas mixture is suppressed, where the turbulent kinetic energy increases in the combustion chamber but decreases at the edge of the cylinder. Also, it is indicated that increasing the RON by 1, mixing 2% volume ethanol, and increasing MON by 1 orderly improve the thermal efficiency. Based on the research and optimization, an evaluation index of anti-knock performance for ethanol-gasoline fuel (EOI*) is proposed, which is suitable for modern engines. From this index, the chemical effect contributes most in the anti-knock performance of ethanol-gasoline mixtures, while the evaporative cooling effect and sensitivity are less and less dominant.

Density functional theory for the thermodynamic gas-phase investigation of butanol biofuel and its isomers mixed with gasoline and ethanol.

Herein, we present the results of our study on the thermodynamic properties of the isomers of butanol (n-butanol, 2-butanol, i-butanol, and t-butanol) to evaluate their thermodynamic potential as a complementary biofuel and/or substitute for ethanol and gasoline. The Gaussian09W software was used to perform molecular geometry optimization calculations using density functional theory with the B3lyp hybrid function using the base set 6-311++g(d,p) and the compound methods G3, G4, and CBS-QB3. Calculations of the fundamental frequency of the molecules were performed to obtain the molecular vibration modes for the respective frequencies. These calculations provided thermodynamic parameters such as the entropy, enthalpy, and specific molar heat at constant pressure, all as a function of the temperature. The parameter values obtained by each method were compared to the experimental values available in the literature. The results showed good accuracy, especially those obtained at the B3lyp/6-311++g(d,p) level for n-butanol. The error between the theoretical and experimental values for the combustion enthalpy of n-butanol was less than 4% at 298.15K; due to the good prediction of its thermodynamic properties, we used n-butanol as a model for the prediction of other thermodynamic properties. We started a molecular docking study of four ligands, namely, n-butanol, ethanol, propanol, heptane, isooctane, and methanol interacting with butanol isomers. The highest values of affinity energy found were for N-butanol. The possible formation of hydrogen bonds, associations by means of London forces, hydrogen, and alkyl interactions were analyzed. n-Butanol was added to ethanol-gasoline mixtures in the temperature range of 298.15 to 600K and the results suggest that n-butanol has a higher calorific value than gasoline-ethanol mixtures in G30E, G40E, G50E, G60E, G70E, G80E, G90E, and E100 blends. As such, n-butanol releases greater amounts of heat during combustion and is thus a viable alternative to biofuels.

Investigation into the Impact of the Composition of Ethanol Fuel Deposit Control Additives on Their Effectiveness

An increasing percentage of ethanol in fuel leads to significant changes in polarity and solubility, which makes conventional gasoline deposit control additives (DCAs) difficult to dissolve in ethanol fuels, resulting in the formation of deposits on engine elements. Critical areas of deposit formation in an engine are constituted by inlet valves, combustion chambers, and fuel injectors. As a consequence, operational parameters of the engine are disturbed to a large extent by the total effect of the deposits. To prevent the aforementioned phenomena, in the operation of engines fueled with ethanol-containing blends, it is necessary to use specifically prepared DCAs. The paper briefly presents a process of development of DCAs dedicated to high-ethanol fuels. Each of the prepared DCA formulations contained a substance having detergent-emulsifying properties (referred to in the text as DEM), a carrier oil, and a solvent. The composition and ratios of components used in the DCA, by testing their effectiveness in engine deposit formation, are verified. A motor station and a test procedure developed for this purpose were used. In search of alternative solutions to conventional polyisobutyleneamines (PIBA) and polyetheramines (PEA) surfactants, which have good solubility in hydrocarbons but not in ethanol, a substance with a benzoxazine structure and a Mannich base were synthesized. Their chemical structures were confirmed by nuclear magnetic resonance (NMR) DCAs were developed, and the effectiveness of their action was verified. Moreover, attention was paid to the dosage level of the DEM and the carrier oil in the DCA. Finally, it was confirmed in the studies carried out that DCAs used for improvement of conventional hydrocarbon engine gasolines are not efficient enough when used in E85 fuels. In the case of the latter, DCAs that have been specifically developed for such fuels should be used, because they have a different chemical structure, and are soluble in the ethanol-gasoline mixture in any ratio of both components.

Hydroxy Gas (HHO) Supplement of Ethanol Fuel Mixture In A Single-Cylinder Spark-Ignition Matic-Engine

<p class="TTPAbstract">Hydroxy Gas (HHO) has been identified as an efficient alternative energy source. HHO is considered an alternative fuel. It can be applied alone or mixed with other kind of fuels in different ratios. In this analysis, the composition of HHO-ethanol was mixed in different variations. Ethanol-HHO was chosen because of its high-octane rating yet low exhaust emissions, and ease of obtaining from engine products. It has been applied on fuel prepared by mixing it with gasoline in various ratios (E30-HHO, E40-HHO, and E50-HHO). The ethanol-HHO mixture has been used in a single-cylinder 4-stroke spark machine for performance, by varying speed of engine from 4000 to 9000 RPM and by applying a platinum spark plug electrode type. In experiments, engine power, average effective pressure (MEP), specific fuel consumption (SFC), and thermal efficiency have been analyzed. The analysis of combustion is accomplished by taking a pressure cycle in the chamber, monitoring the automatic control of engine control unit (ECU) and ensuring utilization in the same parameters of the various fuels tested, in addition to the fuel injection time, which increases with increasing ethanol percentage. Optimal power, MEP and thermal efficiency values are obtained with ethanol-gasoline (E50-HHO) mixture which is operated at 7200 rpm, an increase of about 5% compared to gasoline. Significant reduction in SFC was observed using HHO-ethanol mixture, reduced by about 6% compared to gasoline.</p>

Novel Method to Estimate the Octane Ratings of Ethanol–Gasoline Mixtures Using Base Fuel Properties

Ethanol blending into gasoline yields a wide range of octane rating responses, most frequently synergistic (i.e., greater than expected by linear blending), but also linear or antagonistic. A new a...

Near-azeotropic volatility behavior of hydrous and anhydrous ethanol gasoline mixtures and impact on droplet evaporation dynamics

After fermentation, the concentration of bioethanol is only 8–12 wt%. To produce anhydrous ethanol fuel, a significant amount of energy is required for separation and dehydration. Once the azeotrope composition is reached, distillation can no longer be exploited for purification and more expensive methods must be used. Replacing anhydrous ethanol fuel with hydrous ethanol (at the azeotrope composition) can result in significant energy and cost savings during production. The goal of this study was to characterize the volatility behavior and the droplet evaporation dynamics of hydrous and anhydrous ethanol gasoline blends. Three hydrous ethanol-gasoline blends (10, 15, and 30 vol%) in which the hydrous ethanol was composed of the azeotropic proportions of ethanol and water, and three anhydrous ethanol gasoline blends (10, 15, and 30 vol%) were prepared and analyzed with the advanced distillation curve method. Distillation curves were obtained for all test fuels and distillate samples were taken during the distillation process. A droplet evaporation model validated with the distillation data was exploited to understand how the non-ideal volatility behavior of these blends, the high heat of vaporization of water, and altered fluid properties can affect the transient droplet evaporation phenomena and thus the fuel's potential to effectively mix with air in direct injection internal combustion engines. Minor differences in the distillation curves and vapor-liquid equilibrium between the hydrous and anhydrous fuels were measured. Droplet modeling results showed that the higher heat of vaporization and viscosity of water relative to ethanol can lead to significant differences in the net droplet evaporation time between the two types of blends, especially at the higher blending ratios evaluated. These results suggest that the presence of water in ethanol-gasoline blends may extend droplet lifetimes and increase the susceptibility of the fuel to form particulate matter emissions. This is the first study to use distillation methods to gain a better understanding of evaporation behavior and the role of water's non-linear vapor-liquid equilibrium on droplet evaporation dynamics.

Ultrasonic Analyzers of Ethanol in Automotive Gasoline

Ultrasonic analyzers of ethanol in automotive gasoline are reviewed. These devices allow determination of the volume fraction of ethanol in ethanol-gasoline mixtures in the range from 0 to 100 %. The relative error of measurement of 5 % volume fraction of ethanol is 0.107–0.427 %, and the relative error of measurement of 100 % volume fraction of ethanol is 0.005–0.021 %. Analysis time is several milliseconds.

Quantification of Ethanol Concentration in Gasoline Using Cuprous Oxide Coated Long Period Fiber Gratings

It is reported a new optical sensing system, based on long period fiber gratings (LPFGs) coated with cuprous oxide (Cu 2 O), for the quantification of ethanol concentration in ethanol-gasoline mixtures. The detection principle is based on the spectral features dependence of the Cu 2 O coated LPFGs on the refractive index of the surrounding medium. The chemical constitution of the ethanol-gasoline samples was obtained by gas chromatography mass spectrometry (GC) and GC thermal conductivity detection. Two different modes of operation are presented, wavelength shift and optical power shift mode of operation, with good linear relations between ethanol concentration and the corresponding spectral features of the LPFGs, R 2 =0.999 and 0.996, respectively. In the range of ethanol concentration up to 30% v/v, the sensitivities were 0.76 ± 0.01 nm/% v/v and 0.125 ± 0.003 dB/% v/v with resolutions of 0.21% v/v and 0.73% v/v and limits of detection of 1.63% v/v and 2.10% v/v, for the for the same operation modes, respectively.

Numerical study of the effect of ethanol blending with gasoline surrogate on pollutant emission in well-stirred reactor

In the present study, the effect of ethanol blending on pollutant emissions in oxidation of ethanol-gasoline mixtures is numerically investigated. In doing so, a jet-stirred reactor (JSR) is considered and one representative of each class of constituting ethanol-gasoline (iso-octane, toluene and hexene as the representative of iso-paraffin, aromatic and olefin respectively) is considered. For validating the numerical results, the available experimental data are used in temperature range of 770–1,220 K, at 10 atm. In order to simulate combustion in JSR, the CHEMKIN II library code is used. Furthermore, a detailed kinetic scheme resulting from merging of validated data for the oxidation of the ethanol-gasoline components is used in the CHEMKIN II library code. Based on the numerical results, it is shown that emissions of CO and CO2 can be reduced with the addition of the ethanol. Furthermore, it is concluded that decreasing C/H ratio by ethanol addition leads to the increase of H2O concentration.

Effect of Ambient Temperature and Fuel on Particle Number Emissions on Light-Duty Spark-Ignition Vehicles

To better understand the impact of ambient temperature and fuel on the emissions of ultrafine particles from spark ignition light-duty vehicles, experiments were conducted to examine the impact of ethanol-gasoline mixtures, compressed natural gas (CNG), and ambient temperature, on the size distribution and number emissions of particles. Vehicles were tested on a chassis dynamometer under controlled conditions of ambient temperature spanning from 60 to 85°F. A dual fuel vehicle operating with CNG and 6% ethanol-gasoline blends (E6); and a flex fuel vehicle operating with four different ethanol-gasoline blends E6, 35% ethanol (E35), 65% ethanol (E65) and 85% ethanol (E85) was evaluated to understand fuel effects. Changes in vehicle operating temperature, which included the combustion air temperature, over the ranges of 60 to 85°F showed no clear impact on fine particle emissions. Likewise, no significant changes in particle number or particle size distributions were observed between CNG and E6 fuels. However, tests with the flex fuel vehicle, which were able to examine higher ethanol concentrations in the fuel showed large decreases in particle number emissions as ethanol levels increased to E65 and E85.

Study Concerning the Corrosive Activity Properties of Monatomic Alcohol-Gasoline Blends

The paper studies the corrosive activity of the monatomic alcohol (ethanol, butanol) - gasoline mixtures on the materials from which the internal combustion engines are made. The corrosive influence of these blends was determined in dependence of their composition. It was established that the addition of butanol and triethylamine in the ethanol-gasoline mixture essentially reduces the corrosive activity of this mixture.

Regulated and unregulated emissions from a spark-ignition engine fuelled with low-blend ethanol–gasoline mixtures

The effects of ethanol addition to gasoline on the exhaust emissions (including regulated and unregulated emissions) and the conversion efficiencies of the three-way catalyst (TWC) were investigated in a three-cylinder spark-ignition (SI) gasoline engine. Three typical fuel blends – commercial 93# (Research Octane Number) gasoline (E0), E10, and E20 (with 0 per cent, 10 per cent, and 20 per cent ethanol in the blends by volume) – were used in the experiment. Unregulated emissions were measured by gas chromatography with a pulsed discharge helium ionization detector. Experimental results show that the regulated emissions of hydrocarbon, carbon monoxide, and nitrogen oxides decreased before and after the TWC with the increase of ethanol fraction in the fuel blends. However, the unregulated emissions of ethanol, acetaldehyde, and formaldehyde increased with the increase of ethanol fraction and decreased with increased engine speed and/or torque. Ethanol emission was not detected when fuelled with gasoline (E0). Ethanol emission was intensively influenced by the exhaust temperature and disappeared when the exhaust temperature was higher than 900 K for E10 and E20 operation. Acetaldehyde emission definitely comes from the oxidation of ethanol; the engine speed and load have opposite effects on acetaldehyde emission. Both ethanol and acetaldehyde can be converted effectively by the TWC. More formaldehyde was emitted at higher engine speed and lower load operating conditions.