Gasoline Engine Emissions Research Articles

Effect of direct water injection on knock suppressing mechanism in a high compression ratio gasoline engine

ABSTRACT A low capacity, boosted gasoline engine is an effective approach to enhancing fuel economy. However, knock combustion poses significant limitations to the practical development of these engines. This study investigated the chemical kinetics and macroscopic properties of engines equipped with direct water injection (DWI) at high compression ratios (CRs) to address knock issues. The results indicated that the generation and consumption pathways of OH and CH2O remain unaffected by water injection. Although water exhibited an opposing effect on the sensitive reactions of OH and CH2O, the production reaction rates of OH and CH2O decrease with water injection. Knock index values at each monitoring point approached zero when the water injection quality exceeds 30%. Additionally, knock suppression effectiveness improved with the advancement of water injection timing. The simulation results indicated that the knock index at high CR decreased from 13.61 to 0.27 when the water/fuel ratio exceeded 30%. The indicated specific fuel consumption decreased by 29.3%, and indicated power increased by 41.8% compared to the original engine. Although NOx and CO emissions increased because of the high CR, the water injection coupled with the compression ratio strategy limited the increase in emissions. These findings indicated that DWI coupled with high CR was advantageous to enhancing fuel economy and reducing emissions in low capacity gasoline engines.

Effect of key structure parameters of passive pre-chamber on in-cylinder combustion processes and emissions within a gasoline engine

Due to increasingly strict global emission regulations and energy conservation policies, gasoline engines are facing significant challenges. Achieving high efficiency and ultra-low emissions in gasoline engines has become a critical technical challenge that requires attention. Pre-chamber (PC) Turbulent Jet Ignition (TJI) is a highly promising technology for improving thermal efficiency and reducing emissions in gasoline engines. This study employs a three-dimensional flow simulation analysis combined with a detailed chemical reaction mechanism. The investigation is based on eight distinct passive PC structural configurations. The effects of various structural parameters, including the orifice number (ON), orifice axis angle (OAA), orifice diameter (OD), and volume ratio (VR), on the in-cylinder combustion process and emission characteristics are investigated, in which the formation of the fire nucleus and the propagation of the flame are intensively involved. The investigation is conducted under equivalence ratio working condition. Among these, the ITE of the best configuration is relatively 5.46% higher than the baseline engine. The combustion duration decreased by 55.95% to 7.4 °CA compared to the baseline engine, while particulate soot emissions also decreased by 51.22%.

Effect analysis on hydrocarbon adsorption enhancement of different zeolites in cold start of gasoline engine based on Monte Carlo method

50%–80% of the hydrocarbons in gasoline engine emissions come from during cold starts. Zeolites are often used to adsorb HCs during gasoline engine cold-starting. In order to investigate the effect of adsorption enhancement of different molecular sieves on HCs during gasoline engine cold-starting. In this paper, the adsorption properties of Beta, MOR and FER zeolites at different temperatures were simulated based on Monte Carlo method using propylene and toluene as probe molecules. The results show that all three molecular sieves exhibit good adsorption properties at low temperatures. The adsorption capacity decreased with increasing temperature. The molecular sieves tend to adsorb molecules with diameters similar to the pore size of zeolite. In addition, the three-dimensional zeolites Beta and FER showed better adsorption properties than the one-dimensional zeolites. Based on Monte Carlo method, the adsorption properties of Beta, MOR and FER molecular sieves were investigated at different temperatures under multi-components using toluene, isopentane, propylene, ethylene, methane and water as adsorbents. The results showed that there was a competitive adsorption among the components due to the limited adsorption sites in the molecular sieve channels. Large molecules such as toluene and isopentane occupied most of the adsorption sites and hindered the adsorption of small molecules.

The effects of limonene and eugenol additives in n-heptane and low-octane gasoline on the emission characteristics and fuel consumption of single-cylinder gasoline engine

This study investigated the effects of two additive polarities: polar (eugenol) and nonpolar (limonene) additives blended into n-heptane and low-octane gasoline. These compounds were chosen due to their unique molecular structure characteristics which influences the exhaust emissions. The physicochemical properties, fuel consumption, and exhaust gas emissions of a single-cylinder gasoline engine were measured. Four fuel blends were created by blending eugenol and limonene on a volumetric basis, n-heptane-eugenol (NHE), n-heptane-limonene (NHL), low-octane gasoline-eugenol (GE), and low-octane gasoline-limonene (GL). Tests were conducted on a single-cylinder gasoline engine. The exhaust gas emissions were analyzed using gas chromatography, and the role of each additive substance in the formation of carbon monoxide (CO), unburned hydrocarbon (HC), residual oxygen (O2), and carbon dioxide (CO2) emissions was validated using Hyperchem simulation and gas chromatography mass spectrometry. Owing to differences in the molecular structure and energy content of the two additives, the fuel consumption of NHE-fueled vehicles increased by 19.69% compared to NHL, whereas GE decreased by 32.15% compared to GL. Owing to the presence of oxygen atoms and low binding energy, blending eugenol with n-heptane and low-octane gasoline significantly reduced CO by 1.87% higher than limonene. However, eugenol’s aromatic structure can only reduce 14.45% of HC emission, while limonene, with its dynamically moving electrons and nonpolar properties can reduce up to 18.24%. It was discovered that the two additives could improve the quality of exhaust gas emissions.

Analysis of Gasoline Engine Exhaust Emissions Using a Hydrocarbon Crack System

The increase in the number of motorbikes as a means of transportation results in increased exhaust emissions resulting from combustion of gasoline engines and is dangerous for human health. The use of a Hydrocarbon Crack System is one solution to reduce exhaust emissions in gasoline engines. Hydrocarbon Crack System can perfect the combustion process resulting in low exhaust emissions. The aim of this research is knowing gasoline engine exhaust emissions using the Hydrocarbon Crack System. The research used experimental methods applied to gasoline engine motorbikes with a fuel injection system. Adding Hydrocarbon Crack System is a tool to break down hydrocarbon elements in fuel gas. The use of the Hydrocarbon Crack System in gasoline engines reduces the levels of HC 20 percent and CO 4 percent exhaust emissions at rpm 5500 and above and the exhaust temperature is 215 degrees celsius so that it can maximize the work of the catalyst.

Effect of Intake Conditions and Combustion Factors on Gasoline and Diesel Engines Performance and Exhaust Emissions

The study aimed to investigate the effects of intake conditions, including water injection, filter presence, and temperature variations, on the performance of petrol and diesel engines. The experiment was conducted on single-cylinder four-stroke engines at varying speeds and loads. The composition of the exhaust emissions was analyzed to determine the combustion method. The results indicated that injecting a mixture of water and air into the engine inlet could reduce engine emissions by 17-33% and exhaust temperature by 13-35% for both engines. When an air filter and water injection were present, air flow restrictions in the air inlet led to better combustion and less unburned mixture due to increased air availability. The study also investigated the impact of combustion parameters on heat generation and emissions inside the combustion chamber of gasoline and diesel engines. The parameters studied included intake temperature, intake pressure, equivalence ratio, compression ratio, engine speed, turbulence kinetic energy, and combustion chamber design. The test results showed that higher intake temperatures lead to increased heat generation, increased overall engine efficiency, and reduced CO2 and NOx emissions in gasoline engines. Increasing the value of the parity ratio also led to improved overall efficiency of the two engines.

Evaluation of gasoline-phthalocyanines fuel blends in terms of engine performance and emissions in gasoline engines

The aim of this study was to perform performance and emission analysis in a spark ignition engine by adding different ratios of Phthalocyanines additive to gasoline fuel. In this study, PH10, PH20 and PH30 blend fuels were prepared by blending fuels containing 10 %, 20 % and 30 % phthalocyanine by volume with pure gasoline, respectively. The blended fuels were tested in a gasoline engine at five different engine speeds under full load and the performance values were measured from the dynamometer connected to the engine and emission values were measured from the emission device connected to the exhaust. Compared to pure gasoline in the experimental study, both the torque value and engine power of the PH10 blend fuel decreased, while the exhaust gas temperature increased. While both torque and engine power of PH20 and PH30 blended fuels increased, exhaust gas temperatures decreased. Specific fuel consumption of PH10, PH20, PH30 blended fuels decreased by 4.93 %, 2.12 % and 8.04 %, respectively, compared to pure gasoline. Phthalocyanines' protective, cleaning, and anti-corrosion properties can lead to a decrease in specific fuel consumption when used as a gasoline additive. In the study, it was concluded that increasing the ratio of phthalocyanines additive in gasoline reduces fuel consumption. PH10, PH20 and PH30 fuel blends resulted in 15.34 %, 19.46 % and 9.61 % increase in CO2 emissions respectively compared to gasoline. In addition, CO emissions of blended fuels decreased compared to gasoline, while NOx and HC emissions increased.

Assessment of gasoline engine performance and emissions powered by different gasoline-water ammonia blends: A Review

As a result of a large number of diseases due to environmental pollution resulting from emissions and fast energy depletion. Many researchers resorted methods to produce a mixture that can be used as fuel and fight these issues. In this work, a mini review was concluded through previous studies to highlight and investigate the effect of using water ammonia solution on the characteristics of IC engines with special focus on gasoline engines. The main findings showed decreased engine performance because ammonia has a lower calorific value and energy density. also, most of the previous contributions highlighted a significant reduction in CO2 and CO emissions for all loads. Using ammonia solution increased NOx emissions slightly.

Assessment of gasoline engine performance and emissions powered by different gasoline-water ammonia blends: A Review

Assessment of gasoline engine performance and emissions powered by different gasoline-water ammonia blends: A Review

Distribution, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons in sediments from Baiyang Lake, China.

The issue of polycyclic aromatic hydrocarbons (PAHs) has been an environmental focus worldwide. In this study, the contents, sources, and ecological risks of sixteen PAHs in the sediment of Baiyang Lake were estimated, and a list of priority pollutants was established. The total PAH contents ranged from 114 to 1010 ng·g-1. The composition of PAHs indicated that 4- to 6-ring PAHs predominated in the sediment samples. The diagnostic ratio analysis showed that combustion sources were predominant for PAHs in Baiyang Lake. Specifically, the positive matrix factorization model indicated that diesel engine emissions, gasoline engine emissions, wood combustion sources, and coal combustion sources contributed 22, 32, 24, and 22% of ∑PAHs, respectively. Based on the sediment quality guidelines, mean effects range median quotient, ecological risk quotient, and toxicity equivalent quotient methods, the comprehensive assessment results of PAHs in Baiyang Lake sediments indicated that the ecological risks were at medium and low levels. The priority pollutant list showed that benzo[b]fluoranthene and benzo[a]pyrene were the highest-priority pollutants and thus should be given more attention.

Influence of Inlet Water Injection on Energy Conservation and Emission of Gasoline Engine

Influence of Inlet Water Injection on Energy Conservation and Emission of Gasoline Engine

Histological features of non-alcoholic fatty liver disease revealed in response to mixed vehicle emission exposure and consumption of a high-fat diet in wildtype C57Bl/6 male mice

Non-alcoholic fatty liver disease (NAFLD) is currently plaguing the population at pandemic proportions and is expected to become more prevalent over the next decade. Recent epidemiological studies have demonstrated a correlation between the manifestation of NAFLD and ambient air pollution levels, which is exacerbated by other risk factors, such as diabetes, dyslipidemia, obesity, and hypertension. Exposure to airborne particulate matter has also been associated with inflammation, hepatic lipid accumulation, oxidative stress, fibrosis, and hepatocyte injury. While prolonged consumption of a high-fat (HF) diet is associated with NAFLD, little is known regarding the effects of inhaled traffic-generated air pollution, a ubiquitous environmental pollutant, on the pathogenesis of NAFLD. Therefore, we investigated the hypothesis that exposure to a mixture of gasoline and diesel engine emissions (MVE), coupled with the concurrent consumption of a HF diet, promotes the development of a NAFLD phenotype within the liver. Three-month-old male C57Bl/6 mice were placed on either a low-fat or HF diet and exposed via whole-body inhalation to either filtered (FA) air or MVE (30 µg PM/m3 gasoline engine emissions + 70 µg PM/m3 diesel engine emissions) 6 hr/day for 30 days. Histology revealed mild microvesicular steatosis and hepatocyte hypertrophy in response to MVE exposure alone, compared to FA controls, yielding a classification of "borderline NASH" under the criteria of the modified NAFLD active score (NAS) system. As anticipated, animals on a HF diet exhibited moderate steatosis; however, we also observed inflammatory infiltrates, hepatocyte hypertrophy, and increased lipid accumulation, with the combined effect of HF diet and MVE exposure. Our results indicate that inhalation exposure to traffic-generated air pollution initiates hepatocyte injury and further exacerbates lipid accumulation and hepatocyte injury induced by the consumption of a HF diet, thereby contributing to the progression of NAFLD-related pathologies.

Influence of direct-injection ratio on combustion and emissions of a stoichiometric spark-ignition dual-injection gasoline engine at different throttle percentages and injection timings of direct-injection

Dual-injection in a spark-ignition engine has attracted extensive attention due to the advantage in controlling mixture formation and particulate emissions. The influence of direct-injection ratio (RDI) on combustion and emissions of a stoichiometric spark-ignition dual-injection gasoline engine at different throttle percentages (TP) and injection timings of direct-injection (DIIT) was investigated experimentally. Experimental results show that at a constant RDI (RDI > 0), the MCP (maximum cylinder pressure)TP=15%, DIIT=280°CA BTDC > MCPTP=15%, DIIT=50°CA BTDC≫MCPTP=7%, DIIT=280°CA BTDC > MCPTP=7%, DIIT=50°CA BTDC. The RDI has a significant effect on low and medium loads and DIIT = 50°CA BTDC. The maximum cylinder pressure, maximum heat release rate and maximum cylinder temperature fall significantly with increasing RDI, and their corresponding crank angles are delayed obviously with increasing RDI. The RDI has an obvious influence on combustion starting point, combustion center and combustion duration at low load and late DIIT. At RDI = 100%, the COVimep (coefficient of variation in indicated mean effective pressure) of TP = 7% and DIIT = 50°CA BTDC reaches the highest value of 13%. Except TP = 7% and DIIT = 50°CA BTDC, the COVimep of other case conditions can be controlled below 5%. At RDI = 50%, BSNOX(brake-specific nitrogen oxides)TP=15%, DIIT=280°CA BTDC emissions are approximately 23.3%, 128.4% and 214.1% higher than BSNOX TP=7%, DIIT=280°CA BTDC, BSNOX TP=15%, DIIT=50°CA BTDC and BSNOX TP=15%, DIIT=280°CA BTDC emissions, respectively. At RDI = 50%, the sootTP=15%, DIIT=50°CA BTDC emission is approximately 49.9% higher than sootTP=7%, DIIT=50°CA BTDC emission, sootTP=7%, DIIT=50°CA BTDC emission is approximately 28.6 times higher than sootTP=15%, DIIT=280°CA BTDC emission, and sootTP=15%, DIIT=280°CA BTDC emission is approximately 11.1% higher than sootTP=7%, DIIT=280°CA BTDC emission. Through comprehensive compromise of combustion and emission performance, the best RDI is 40%–60%.

Comprehensive study on using hydrogen-gasoline-ethanol blends as flexible fuels in an existing variable speed SI engine

The rising human population is causing the utilization of enormous amounts of fossil fuels to fulfill energy needs. Various renewable sources are used as fossil fuels however those resources are not powerful in supplanting customary non-renewable energy sources like gasoline in vehicles. The depletion of conventional fossil fuel utilized in a vehicle contributes to an increased portion of air contamination and is a danger to human well-being. Also, to maintain the supply demand, many active types of research have been carried out in mixing a higher percentage of ethanol over gasoline and further moving towards flex-fuel vehicles. But there arises a problem of knocking and higher CO, and HC emissions from the engine. To overcome the above problem, ethanol could be mixed in a higher percentage over gasoline with the help of hydrogen assistance and can completely avoid the problem of knocking and reducing CO and HC emissions. In this research, the combustion, emission, and performance characteristics of a variable-speed gasoline engine fuelled with ethanol-blended gasoline along with hydrogen assistance are taken for investigation at variable speeds like 1800, 1600, 1400, and 1200 rpm. Hydrogen is added to blended fuel (E30) which has better combustion, emission, and performance than other blended fuels. Hydrogen addition is done at 2, 3, and 4 ms respectively. The outcomes showed that the E30 + H2 at 3 ms has better combustion, emission, and performance, still, the emission of NOx is higher in comparison with all the other blends due to complete combustion. Thus, a two-stage analysis has been done, one is making a comparison among various blends of ethanol, and the second one is the comparison among the various energy shares of hydrogen.

Modeling of combustion and emissions behavior on the effect of ethanol–gasoline blends in a four stroke SI engine

Researchers are increasingly coming up with creative solutions to reduce fuel consumption and harmful emissions due to the political unrest around crude oil and harsher environmental legislation around the globe. Using gasoline and ethanol blends as substitutes in SI engines is thought to be a promising approach. To lower the cost of experimental test, it is still necessary to provide a model to explore the emissions, performance and combustion of ethanol mixtures in petrol engine under various operating situations. A comprehensive quasi dimensional two zone model was used. This mathematical model could predict and analyze the engine combustion, emissions and performance parameters using MATLAB. The thermal efficiency was improved for E20 by 3%. Ethanol addition decreased SFC value by average 7.2% for E20 with respect to gasoline. In comparison to gasoline, the increases in output power were 1.1%, 3%, 4%, and 5.5% are obtained with E5, E10, E15, and E20. and 45% The highest increases in peak cylinder pressure and cylinder temperature for E20 about gasoline are 14 and 11%, respectively about gasoline. At 2500 rpm, the greatest percentage declines in NOx, CO, and HC emissions for E20 are 3.3, 23.5 and 45% about gasoline. The results of comparing the mathematical model’s validity to those acquired from experimental data and diesel RK software demonstrate that the MATLAB code is appropriate. The mathematical model proved that ethanol blending can be used up to 20% as alternative fuels to improve the gasoline engine performance, combustion and emissions.

Reducing gasoline engine emissions using novel bio-based oxygenates: a review

Reducing gasoline engine emissions using novel bio-based oxygenates: a review

Experimental Investigation for Improving Performance and Emissions of Gasoline Engine by Adding HHO Gas

Experimental Investigation for Improving Performance and Emissions of Gasoline Engine by Adding HHO Gas

Korelasi Konsentrasi Etanol 5% Pada Bahan Bakar Gasolin Terhadap Performa, dan Emisi Gas Buang Mesin Bensin 150cc

Ethanol has higher octane and oxygen properties than fossil-fuel gasoline. Along with the increase in gasoline dependency and exhaust emissions, the use of ethanol as a fuel is urgently studied. This study aimed to observe the concentration of 5% ethanol in gasoline on the performance and exhaust emissions of a 150cc gasoline engine that was operated at 1000, 2000, and 3000rpm. The observation results show that the concentration of 5% ethanol in gasoline correlates with an increase in performance with indications of an increase in EGT, Brake power, BTE, and a decrease in SFC. On the emission side, it is also correlated with an increase in the quality of exhaust emissions with indications of increased CO2 emissions and reduced CO and HC emissions. The best correlation of 5% ethanol concentration was obtained at an operating speed of 2000rpm with an increase in EGT of 10.70%, an increase in Brake power of 9.49%, an increase in BTE of 38.62%, an increase in CO2 emissions of 23.06%, a decrease in SFC of 26 .49%, CO emission reduction of 16.67%, and HC emission reduction of 4.24%.

Throttling Effect on the Performance and Emissions of a Multi-Cylinder Gasoline Fuelled Spark Ignition Engine

The throttle mechanism, a regulatory technique of engine output, is accompanied by a loss of some energy. The effect of intake air throttling on the performance and emissions of a multi-cylinder spark ignition gasoline engine was experimentally investigated. The engine was coupled to a hydraulic dynamometer equipped with a customized cooling system for both the engine and dynamometer. Experimental tests were performed for various engine speeds and air-fuel ratios at the WOT and POT conditions with optimized ignition timing. The acquired results recorded that a better engine operation could be achieved with WOT in terms of bmep, bsfc, ηb, CO, CO2 and UHC compared to POT. At the same time, the worst trend at WOT was noticed for the NOx concentration due to the higher conversion efficiency of fuel combustion. In terms of engine speed for both WOT and POT conditions, operating at 3000 rpm represents the minima of ϕ, bsfc, CO and UHC; and the maxima of ηb, CO2 and NOx with some fluctuation on both sides of this point. Maximum recorded values of ηb were about 30.55% and 28. 55%, while the minimum values of bsfc were about 274 and 293 g/kW.h for the WOT and POT conditions, respectively. The maximum bmep was obtained at 2500 rpm at WOT and POT conditions with values of about 940 kPa and 904 kPa, respectively. Maximum recorded values of NOx were about 1525 and 977 ppm for the WOT and POT conditions, respectively.

Experimental investigation and performance prediction of gasoline engine operating parameters fueled with diisopropyl ether-gasoline blends: Response surface methodology based optimization

In this research, gasoline engine performance and emission characteristics were studied when powered by diisopropyl ether-gasoline blends. The main objective of this study is to determine the behavior of diisopropyl ether-gasoline blends at various engine speeds and compression ratios. Further, the engine parameters were optimized using the response surface methodology. Enriched oxygen, higher latent heat of vaporization, and the readily volatile nature of the fuel enhanced the brake thermal efficiency and lowered the hydrocarbons and carbon monoxide due to a better combustion rate. The developed model exhibited superior R2 values with a 0.957 desirability factor. The optimum parameters such as speed, compression ratio, and fuel-blend concentrations were found at 2250 rpm, 10:1, and D25 (75% gasoline and 25% diisopropyl ether), respectively. The responses for the optimal input parameters were brake thermal efficiency (31.53%), specific fuel consumption (0.2923 kg/kWh), carbon monoxide (0.14% by Vol.), hydrocarbons (31 ppm), and oxides of nitrogen (708 ppm). The predicted values for optimum engine parameters were validated with the experimental data, and their percentage of absolute error was found to be less than 5%. Thus, the study concludes that diisopropyl-ether gasoline blends can be used as an alternative fuel to enhance the brake thermal efficiency and reduce the pollution level, and the proposed numerical model can predict the responses with high accuracy.