Gasoline Engine Emissions Research Articles

Performance and exhaust gas emission of gasoline engine fueled by gasoline, acetone and wet methanol blends

Increased motor vehicles have resulted in increased fuel consumption and emissions. Pramium fuel has an octane value of 88. Acetone 110 octane value and wet methanol 113 octane value. Mixing of premium acetone and wet methanol is expected to improve engine performance and reduce emissions. Research using gasoline engines with electronic fuel injection (EFI) systems. The results of the testing, there was a 12.62% increase in brake power. Brake specific fuel consumption (BSFC) has increased by 4.35% compared to P100. The increase in BSFC was due to the calorific value of acetone and wet methanol which was lower than the premium. The resulting CO and HC emissions have decreased. The decrease in CO emissions reached 87.5%. The lowest level of HC produced reaches 46 ppm. Mixing acetone and wet methanol into the premium can improve engine performance. It can be seen from the increase in brake power produced. Exhaust emissions are produced better. CO and HC levels have decreased.

STATISTICAL EVALUATION OF GASOLINE ENGINE EMISSIONS WITH La2O3/Zn/Na CATALYST

The results of gasoline engine emissions purchased by the Toyota ANZ1 are statistically evaluated with the catalyst developed (La2O3/Zn/Na). The tests were carried out in the combustion test bench developed. The results show that the percentage of CO emissions increases as the engine speed increases, reaching values higher than 4%, with the original catalyst being that with the catalyst developed, which contains 5% by weight of Lanthane emissions of CO are close to 2%, but when the engine doesn´t have the oxygen sensor. When the concentration of Lanthane is 7,5%, the efficiency reaches 7% of CO removal and 32% of HC removal. The statistical test T for independent samples indicates that the original catalyst and that developed presently a statistically significant difference in catalytic efficiency. On the contrary, when the oxygen sensor is connected, the catalyst developed is also efficient. On the other hand the emissions of HC decrease as the engine speed increases reaching values close to 200ppm which corresponds to the EURO III standard, being that with the catalyst developed, which contains 7,5% by weight of LNG, the HC emissions It is 147ppm showing good performance.

Particle Emission of the Direct-injection Gasoline Engine under Real Driving Emissions Conditions

Particle Emission of the Direct-injection Gasoline Engine under Real Driving Emissions Conditions

Precision Forming and Machining Technologies for Ceramic-Based Components

Structural ceramics components for industrial use are classified under two categories: one that is originally designed for ceramics (Ceramic Origin), and the other that is originally designed for metals and subsequently replaced with ceramics because of their improved hardness and resistance to both heat and corrosion (Metal Origin). Ceramic insulators for power lines and catalytic substrates used to control automotive emissions in gasoline engines are “Ceramic Origin” components. As ceramics are difficult to machine, a precision mold has been used in the forming process to minimize the machining volume in the case of “Ceramic Origin” components. Meanwhile, ceramic turbo charger rotors and valves for automotive engines are “Metal Origin” components, which not only require durability under severe operating conditions but also severe dimensional accuracy, similar to metal parts. These components have been derived from extensive R&D efforts in materials and process technologies for ceramic gas turbines, which have been implemented in the majority of advanced countries since the 1970s. This paper includes some examples of precision forming and machining technologies for both types of ceramic components developed by NGK Insulators, Ltd., and highlight their issues. Finally, the possibility of new types of ceramic-based components will be introduced.

Approaches and solutions to HCCI - a review energy systems: fuel and combustion, injection and atomization

SI and CI engines are entities in which conditions of internal combustion was triumphantly implemented. In a gasoline engine both efficiency and emissions are less; on the other hand in a diesel engine both are relatively high. It is hard to achieve a win-win situation where fuel consumption and adverse impact on the environment were diminished. Over the past few decades researchers have assigned themselves to strike a balance in this regard, creating Homogeneous charge compression ignition engine technology, which perfectly amalgamates the principles of Spark Ignition and Compression Ignition engines, making it the holy grail of engines. Homogeneous charge compression ignition engines do not employ spark plug or fuel injector to initiate combustion, the lean homogeneous mixture auto-ignites in multitudinous spots once it is compressed to attain its chemical activation energy. Unlike its contemporaries the combustion is flameless, propelled the fuel efficiency along with an enormous decrease in emissions. This proposed work digs deep into conceptual description of the fundamentals of HCCI engine and various approaches to attain HCCI, along with the challenges encountered related to the same being elaborated. Depending on inferences arrived from the challenges different controlling strategies are proposed in this paper.

Primary and secondary organic aerosols in summer 2016 in Beijing

Abstract. To improve air quality, the Beijing government has employed several air pollution control measures since the 2008 Olympics. In order to investigate organic aerosol sources after the implementation of these measures, ambient fine particulate matter was collected at a regional site in Changping (CP) and an urban site at the Peking University Atmosphere Environment Monitoring Station (PKUERS) during the “Photochemical Smog in China” field campaign in summer 2016. Chemical mass balance (CMB) modeling and the tracer yield method were used to apportion primary and secondary organic sources. Our results showed that the particle concentration decreased significantly during the last few years. The apportioned primary and secondary sources explained 62.8 ± 18.3 and 80.9 ± 27.2 % of the measured OC at CP and PKUERS, respectively. Vehicular emissions served as the dominant source. Except for gasoline engine emissions, the contributions of all the other primary sources decreased. In addition, the anthropogenic SOC, i.e., toluene SOC, also decreased, implying that deducting primary emissions can reduce anthropogenic SOA. In contrast to the SOA from other regions in the world where biogenic SOA was dominant, anthropogenic SOA was the major contributor to SOA, implying that deducting anthropogenic VOC emissions is an efficient way to reduce SOA in Beijing. Back-trajectory cluster analysis results showed that high mass concentrations of OC were observed when the air mass was from the south. However, the contributions of different primary organic sources were similar, suggesting regional particle pollution. The ozone concentration and temperature correlated well with the SOA concentration. Different correlations between day and night samples suggested different SOA formation pathways. Significant enhancement of SOA with increasing particle water content and acidity was observed in our study, suggesting that aqueous-phase acid-catalyzed reactions may be the important SOA formation mechanism in summer in Beijing.

A novel biomass lubricant filter and its effect on gasoline engine emissions and fuel economy

With the increasing number of light-duty passenger car, a large amount of waste engine oil was produced yearly which has polluted the environment and wasted fossil resources. Extend engine oil drain interval and reduce its effect on engine emission is of great importance. In this paper, a kind of modified-sawdust engine oil filter was developed and the study focus on its effect on the emission characteristics and fuel consumption rate of spark ignite gasoline engine. This modified-sawdust engine oil filter was also compared with common oil filter. The tests were performed in four-cylinder direct injection gasoline engine at six different typical operating conditions. Various tests were proceed including the exhaust emissions measurement of nitrogen oxides (NOx), carbon monoxide (CO) and hydrocarbons (HC) as well as the fuel consumption rate measurement. The effect of engine oil change on engine emission and fuel consumption rate were also studied. Impurity element content of waste oil and kinetic viscosity were measured before and after modified oil filter was used. The results show that relative to common oil filter, the modified-sawdust oil filter has 0.4–2.1%, 3.7–7.5%, 1.6–13.3% decrease for CO, HC, NOx emissions, respectively. In addition, it significantly reduces oil consumption, and the three major emission species (CO, HC and NOx) was also reduced when fresh engine oil was adopted. These results indicate that the use of modified-sawdust oil filter is an effective choice to improve gasoline engine emission and fuel economy.

Effect of internal and external EGR on cyclic variability and emissions of a spark ignition two-stroke cycle gasoline engine

Conventional two-stroke cycle engine suffers from typical drawbacks including lower combustion efficiency and excessive emissions of uHC and CO which are largely due to low in-cylinder average charge temperature at low load and speed regions of engine operating conditions. Utilising the hot burned Exhaust Gas Recirculation (EGR) technique can boost the in-cylinder average charge temperature of the engine. The influence of hot burned gases applied by means of both Internal EGR and External EGR strategies on the combustion stability and exhaust gas emission of a single-cylinder two-stroke cycle engine running at low-load and mid-load of operating conditions was investigated experimentally along with simulation works using 1-D engine simulation code. The results indicated that both In-EGR and Ex-EGR improved the combustion stability (lower misfire cycle) and decreased the concentrations of uHC and CO emissions, specifically at low speed region; however, NOx concentration was increased. At Internal EGR setting of 30%, the Coefficient of Variation for maximum in-cylinder pressure (COVPmax) reached the minimum by 5.64 while when External EGR percentage was 25%, COVPmax approached about 6.67 at the mid-speed (2000 rpm) of engine operating condition.

Occupational exposures to leaded and unleaded gasoline engine emissions and lung cancer risk

ObjectivesTo determine whether occupational exposure to gasoline engine emissions (GEE) increased the risk of lung cancer and more specifically whether leaded or unleaded GEE increased the risk.MethodsTwo population-based case–control studies...

Investigation on performance of a spark-ignition engine fueled with dimethyl ether and gasoline mixtures under idle and stoichiometric conditions

This study investigated effects of dimethyl ether addition on the gasoline engine combustion and emissions performance under idle and stoichiometric conditions. The engine was first modified to be fueled with gasoline and dimethyl ether simultaneously. The experimental results showed that, with the increase of dimethyl ether energy fraction in the total fuel, the total fuel energy flow rate was decreased, and the flame development and propagation periods were shortened. The cycle-to-cycle variation was reduced and the degree of constant volume combustion was increased after the dimethyl ether addition. The dimethyl ether blending was beneficial for reducing hydrocarbon and nitrogen oxide emissions from 1951 and 95 ppm of the original engine to 552 and 34 ppm of pure dimethyl ether, respectively. Meanwhile, with the increase of dimethyl ether addition level, the peak cylinder pressure and carbon monoxide emission were decreased at first, whereas increased when the dimethyl ether energy fraction exceeded 49%. Furthermore, heat release rate during the low temperature reaction was enhanced with the increase of dimethyl ether addition level. The maximum heat release rate was heightened and its relevant crank angle was advanced during the high temperature reaction period after the dimethyl ether enrichment.

High emission reduction performance of a novel organic-inorganic composite filters containing sepiolite mineral nanofibers

In this work, a new organic-inorganic composite filter was prepared. The thickness, pore size, air permeability, bursting strength and microstructure were characterized systematically, proving that coatings had regulatory effect on filters physical properties. Benefitting from the distinct coatings containing 5% sepiolite nanofibers after five times dilution, the physical properties of corresponding air filter exhibits the most favorable performance and meet the standard of air filter. When used as fuel filter, it satisfies the fuel filter standard and achieves the best performance after six times dilution. The contrast test on engine emission was taken based on auto filters coated with/without as prepared nanofibers. An obvious decrease in the emission of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NOx) can be observed after installation of composite filter on vehicles. Under the high idle condition, gasoline engine emission decreased by 8.13%, 11.35% and 44.91% for CO, HC and NOx, respectively. When tested in the low idle condition, engine emission reduced by 0.43%, 1.14% and 85.67% for CO, HC and NOx, respectively. The diesel engine emissions of CO, NOx and total amount of HC and NOx decreased by 32.26%, 3.28% and 4.66%, respectively. The results illustrate the composite installation exhibits satisfactory emission reduction effect.

An experimental study of the performance and emissions of spark ignition gasoline engine

The resistance of gasoline to knocking is critically determined by the octane number. The engine will encounter a significant waste of power, reduced efficiency and enhanced emission levels if a well-defined gasoline octane number is not employed. In this study, the engine performance and emission of hazardous gases were experimentally investigated through the use of three gasoline fuels (RON95, 97 and 102). The engine selected for the testing was a 1.6-L four-cylinder Toyota 4A-GE Blacktop VVT with the original ECU. The engine was run at different constants for various part load conditions as well as at constant throttle body. The engine that was operated with RON97 fuel was found to display positive improvements in terms of the brake specific fuel consumption of the engine, reduced at an average of 5 and 10%, compared to RON102 and RON95 fuels, respectively. Furthermore, the engine operated with RON102 fuel exhibited higher torque and engine power compared to RON97 and RON95. The brake thermal efficiency for both RON97 and RON102 fuels was remarkably improved at an average of 12% compared to RON95. The incorporation of RON102 fuel reduced the emission of NOX compared to RON95 and RON97 fuels at an average of 34% and 40%, respectively. The RON102 fuel produced the highest HC emission compared to RON97 and RON95. The CO emission was found to be higher for RON102 fuel compared to RON97 and RON95 at an average of 12.4% and 17%, respectively. The study concluded that although engine performance and efficiency versus gasoline depend highly on the engine design parameters, RON97 is able to deliver high performance and efficiency in all conditions. Therefore, it is recommended that RON97 be used instead of RON95 to achieve better performance with this type of engine.

Effects of Biofuel and Variant Ambient Pressure on FlameDevelopment and Emissions of Gasoline Engine.

There are many technologies about exhaust emissions reduction for wide variety of spark ignition (SI) engine have been considered as the improvement throughout the combustion process. The stricter on legislation of emission and demands of lower fuel consumption needs to be priority in order to satisfy the demand of emission quality. Besides, alternative fuel such as methanol-gasoline blends is used as working fluid in this study due to its higher octane number and self-sustain concept which capable to contribute positive effect to the combustion process. The purpose of this study is to investigate the effects of methanol-gasoline fuel with different blending ratio and variant ambient pressures on flame development and emission for gasoline engine. An experimental study is carried towards to the flame development of methanol-gasoline fuel in a constant volume chamber. Schlieren optical visualization technique is a visual process that used when high sensitivity is required to photograph the flow of fluids of varying density used for captured the combustion images in the constant volume chamber and analysed through image processing technique. Apart from that, the result showed combustion burn rate increased when the percentage of methanol content in gasoline increased. Thus, high percentage of methanol-gasoline blends gave greater flame development area. Moreover, the emissions of CO, NOX and HC are performed a reduction when the percentage of methanol content in gasoline is increased. Contrarily, the emission of Carbon dioxide, CO2 is increased due to the combustion process is enhanced.

Effect of Circuit Geometry on Steady Flow Performance of an Automotive Turbocharger Compressor

Downsizing and turbocharging are today considered an effective way to reduce CO2 emissions in automotive gasoline engines. To this aim, a deep knowledge of turbocharger behavior could be a key solution to improve the engine-turbocharger matching calculation. The influence of the intake system geometry on the surge line position is an important aspect to guide the project of the intake manifold, enlarging the compressor stable zone. This aspect has a considerable impact on engine performance, especially during transient operation. A wide experimental investigation was carried out at the turbocharger test facility of the University of Genoa on a small turbocharger compressor. Compressor characteristic curves measured considering an automotive intake circuit are compared with standard maps provided by turbocharger's manufacturer. This information allows the optimization of 1D model implementing more realistic maps of compressor. The influence of three different layouts has been investigated varying overall circuit volume and length, keeping values in a range compatible with passenger cars packaging constraints. In the paper, the main results of the experimental campaign are presented taking into account the influence of geometry variations on compressor map and surge line position.

Source apportionment research of fine particulate matter in the atmosphere by PAHs

Haze weather frequently occurs in many cities in China. Polycyclic aromatic hydrocarbons(PAHs) in fine particulate matter(PM2.5) can adversely affect the environment and human health. In this paper, PM2.5 samples were collected at nine sites in a city in northeastern China from September 2013 to October 2014. Sixteen USEPA(US Evironment Protection Agency) priority PAHs in PM2.5 were analyzed to determine their spatial and temporal distribution characteristics. The source apportionment of PAHs was conducted with the Positive Matrix Factorization(PMF) model. The results indicate that the concentrations of total PAHs(T-PAHs) in PM2.5 are within the range of 0.26 to 72.48 ng/m3. The seasonal variation of T-PAHs is winter>spring>autumn>summer, and the space distribution of PAHs is JZP>DP>BFH>LP> EESA>IPT>CP>HZMC>JYP. In all types of PAHs, three-ring and five-ring PAHs are significantly prominent(62%) in the heating period due to petrogenic sources and traffic emissions. Middle- and high-ring PAHs in the non-heating period are caused by coal combustion and vehicle exhaust, which accounts for 77% of the total emissions. The source apportionment results obtained by the diagnostic ratio of PAHs reflect that coal burning, traffic and other sources have a distinct influence on PAH emissions in this city. Six factors are defined by PMF v5.0, namely, coke oven emissions(7.7%), biomass burning(44.3%), petrogenic sources(10.7%), coal combustion(10.4%), gasoline engine emissions(16.7%), and diesel engine emissions(10.3%). The results indicate that the PAHs in PM2.5 in the city are primarily caused by combustion processes and vehicle exhaust.

Experimental investigation on the influences of exhaust gas recirculation coupling with intake tumble on gasoline engine economy and emission performance

To improve the economy and emission performance of gasoline engine under part load, the approach of exhaust gas recirculation coupling with intake tumble was investigated by bench testing. Based on a naturally aspirated gasoline engine, the sweeping test of exhaust gas recirculation rate was conducted in two intake modes (with/without intake tumble), and the parameters related to engine heat-work conversion process and emission performance were measured. Through comparing and analyzing the measured data, the effects of exhaust gas recirculation coupling with intake tumble on gasoline engine economy and emission performance were revealed. The results show that pumping loss decreases gradually while in-cylinder residual gas fraction increases linearly with the exhaust gas recirculation rate increasing; the high-pressure cycle efficiency ascends with exhaust gas recirculation rate increasing due to the decrease of heat transfer loss and exhaust gas energy loss. Thus, the improvement of indicated thermal efficiency is the superposition of double benefits of low-pressure cycle and high-pressure cycle. At 1600r/min and 2.94bar, the indicated thermal efficiency can be increased by 4.29%. With the increase of exhaust gas recirculation rate, nitrogen oxide emissions almost fall linearly, but hydrocarbon and carbonic oxide emissions have no obvious change in the effective range of exhaust gas recirculation rate. The biggest advantage of intake tumble is that it can extend the effective range of exhaust gas recirculation rate. As a result, the potential of energy conservation and emission reduction of exhaust gas recirculation is largely improved.

Simulations of gasoline engine combustion and emissions using a chemical-kinetics-based turbulent premixed combustion modeling approach

This work presents a turbulent premixed combustion modeling approach which is based on chemical kinetics. In this approach, the smallest length scales are of the order of 0.1–1.0 mm for typical engine simulations with a Reynolds-averaged Navier–Stokes turbulence model and, after adaptive mesh refinement technology is used to consider the magnitude of the subgrid field, the Reynolds-averaged Navier–Stokes turbulent flow field can be well resolved. For solution of the flame front, an artificially thickened laminar flame concept is introduced to balance the computational accuracy and the computational cost. Around the artificially thickened laminar flame front, a special grid resolution strategy is designed, i.e. using much finer resolution in the normal direction of the flame front and typical adaptive mesh refinement resolution in the other two perpendicular directions. Then, chemical kinetics can be applied to the chemistry process which occurs in the flame front. To use this chemical-kinetics-based turbulent premixed combustion modeling approach better, a good chemical kinetics mechanism is very important. For this reason a practical primary-reference-fuel chemical kinetics mechanism is improved and validated in present work. The newly improved mechanism resolves several issues in the existing mechanisms, including unrealistically fast autoignition reactions and limited laminar flame speed validation. After reoptimization of those laminar-flame-speed-related reactions, the new mechanism can correctly compute the laminar flame speeds for a wide range of Ford spark ignition engines and for various operating conditions. Using this combustion modeling approach together with the new mechanism, simulations of the combustion and the emissions of several spark ignition engines for typical operating conditions were carried out. The simulated in-cylinder pressures, the simulated burn rates, and the simulated emissions including the brake specific carbon monoxide emissions, the nitrogen oxide emissions, and the unburned hydrocarbon emissions are compared with the experimental data, and very good agreement is found without tuning any model constants.

Metabolomic changes in murine serum following inhalation exposure to gasoline and diesel engine emissions

The adverse health effects of environmental exposure to gaseous and particulate components of vehicular emissions are a major concern among urban populations. A link has been established between respiratory exposure to vehicular emissions and the development of cardiovascular disease (CVD), but the mechanisms driving this interaction remain unknown. Chronic inhalation exposure to mixed vehicle emissions has been linked to CVD in animal models. This study evaluated the temporal effects of acute exposure to mixed vehicle emissions (MVE; mixed gasoline and diesel emissions) on potentially active metabolites in the serum of exposed mice. C57Bl/6 mice were exposed to a single 6-hour exposure to filtered air (FA) or MVE (100 or 300 μg/m3) by whole body inhalation. Immediately after and 18 hours after the end of the exposure period, animals were sacrificed for serum and tissue collection. Serum was analyzed for metabolites that were differentially present between treatment groups and time points. Changes in metabolite levels suggestive of increased oxidative stress (oxidized glutathione, cysteine disulfide, taurine), lipid peroxidation (13-HODE, 9-HODE), energy metabolism (lactate, glycerate, branched chain amino acid catabolites, butrylcarnitine, fatty acids), and inflammation (DiHOME, palmitoyl ethanolamide) were observed immediately after the end of exposure in the serum of animals exposed to MVE relative to those exposed to FA. By 18 hours post exposure, serum metabolite differences between animals exposed to MVE versus those exposed to FA were less pronounced. These findings highlight complex metabolomics alterations in the circulation following inhalation exposure to a common source of combustion emissions.

Effect of spark timing on combustion and emissions of a hydrogen direct injection stratified gasoline engine

The effect of spark timing on combustion and emissions of a hydrogen direct injection stratified gasoline engine was investigated. The engine was operated at 1500 rpm and excess air ratio at 1.2. It was found that when the hydrogen volume fraction was raised from 0% to 10%, and the hydrogen injection timing was 110 °CA BTDC a good stratified effect was achieved. The spark timing was varied from 4 to 16 °CA BTDC. This test demonstrated that the brake thermal efficiency first rose and then fell with the spark advance angle increased. In addition, it increased with the increase of hydrogen volume fraction. Postponing the spark timing caused the maximum instantaneous heat release rate increase. The peak cylinder pressure and the maximum rate of pressure rise increased with spark advance angle increase. Postponing the spark timing also caused NOx, HC and CO emissions to decrease. When the hydrogen volume fraction increased, the NOx emissions rose and the HC and CO emissions dropped.

Effect of hydroxy (HHO) gas addition on gasoline engine performance and emissions

The objective of this work was to construct a simple innovative HHO generation system and evaluate the effect of hydroxyl gas HHO addition, as an engine performance improver, into gasoline fuel on engine performance and emissions. HHO cell was designed, fabricated and optimized for maximum HHO gas productivity per input power. The optimized parameters were the number of neutral plates, distance between them and type and quantity of two catalysts of Potassium Hydroxide (KOH) and sodium hydroxide (NaOH). The performance of a Skoda Felicia 1.3 GLXi gasoline engine was evaluated with and without the optimized HHO cell. In addition, the CO, HC and NOx emissions were measured using TECNO TEST exhaust gas analyzer TE488. The results showed that the HHO gas maximum productivity of the cell was 18L/h when using 2 neutrals plates with 1mm distance and 6g/L of KOH. The results also showed 10% increment in the gasoline engine thermal efficiency, 34% reduction in fuel consumption, 18% reduction in CO, 14% reduction in HC and 15% reduction in NOx.