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2017-10-08
Technical Paper
2017-01-2392
Matthew Duckhouse, Mark S. Peckham, Harry Bradley
An on-board version of a fast response chemiluminescence analyzer with a 3 millisecond response time enables the recording of high temporal resolution transient NOx emissions during cold start and pull-away, gear changes, speed bumps and other real world transient conditions. Tests were performed on a 1.6 litre turbo GDI vehicle. The data has been correlated with on-board engine data available from the vehicle’s electronic control unit to study the underlying causes of these short-duration events. Exhaust gas was sampled from after the catalyst but before the silencer (muffler) to preserve all high frequency detail and to allow accurate integration of pollutant concentration and measured engine exhaust mass flow. Various aspects of the vehicle’s calibration are seen to contribute to the short-duration bursts of tailpipe emissions which would not be visible with slower response analyzers.
2017-10-08
Technical Paper
2017-01-2184
Vincenzo De Bellis, Fabio Bozza, Daniela Tufano
Nowadays, the development of a new engine is becoming more and more complex due to conflicting factors regarding technical, environmental and economic issues. Hence, the experimental activity has to comply with the above complexities, resulting in increasing cost and duration of engine development. For this reason, the simulation is becoming increasingly important, thanks to its lower financial burden, together with the need of an improved predictive capability. Among the other numerical approaches, the 1D models represent a proper compromise between reliability and computational effort, especially if the engine behavior has to be investigated over a number of operating conditions. The combustion model has a key role in this contest and the research of consistent approaches is still on going. In this paper, two well-assessed combustion models for Spark Ignition (SI) engines are described and compared: the eddy burn-up theory and the fractal approach.
2017-10-08
Technical Paper
2017-01-2225
Joe Robinson
The EPA's Federal Test Procedure showed a 45% improvement in miles per gallon with no loss of power when implementing these modifications. The modifications redesign the head of the gasoline engine so that the real compression ratio is reduced to 5 to 1, while the real expansion ratio is increased to 1 to 15. This is accomplished by raising the height of the piston to increase both the compression ratio and the expansion ratio initially to 15 to 1. Although the intake valve is closed at bottom dead center, the compression ratio is then reduced to 5 to 1 by allowing the air/fuel mixture in the combustion chamber to be shared with a decompression tank during most of the compression stroke. In addition to the standard intake and exhaust valves, there is a third valve which controls the opening between the combustion chambers and the decompression tank. This avoids any late intake valve closing. The decompression tank and all valves are in the two section head.
2017-10-08
Technical Paper
2017-01-2182
Xikai Liu, Xingyu Liang, Yonge Wu
According to the study of the soot emission in marine diesel, ,a new reduced mechanism for n-heptane was constructed to describe the combustion process in diesel engine by using sensitivity analysis.Furthermore,verifying the ignition delay time,the laminar flame speed,the flame propagation distance and species profiles in combustion process by using Chemkin Pro in different pressure(13.5atm and 42 atm),initial temperatures and equivalence ratio(0.5 and 1.0).Then,compare the simulated result with the experiment data and the simulated result by using LLNL(lawrence livermore national laboratory)detail mechanism and SKLE(state key laboratory of engine)mechanism.It is demonstrated that the reduced mechanism can not describe the ignition delay time in low temperature.And then,the reduced mechanism was adjusted and optimized to make it more close to the experiment data,and the reduced mechanism were able to predict ignition delay time,laminar flame speed,flame propagation distance and species profiles.The final reduced n-heptane mechanism are more compact compare with the current detailed mechanisms in literature.Thus,this reduced n-heptane mechanism can reduce the pressure of calculation and save the calculation time.
2017-10-08
Technical Paper
2017-01-2190
Alessandro D'Adamo, Marco Del Pecchia, Sebastiano Breda, Fabio Berni, Stefano Fontanesi, Jens Prager
CFD simulations of reacting flows are fundamental investigation tools used to predict combustion behaviour and pollutants formation in modern spark-ignition internal combustion engines. Most of the flamelet-based combustion models adopted in current simulations use the fuel/air/residual laminar flame speed as a background to predict the turbulent flame speed. This in turn is a fundamental requirement to model the effective burn rate. The consolidated approach in engine combustion simulations relies on the adoption of empirical correlations for laminar flame speed, which are derived from fitting activity of combustion experiments. However, these last are conducted at largely different pressure and temperature ranges from those encountered in engines: for this reason, correlation extrapolation at engine conditions is inevitably accepted and relevant differences between proposed correlations emerge even for the same fuel and conditions.
2017-10-08
Technical Paper
2017-01-2209
Christian Ibron
Partially premixed combustion (PPC) can be applied to decrease emissions and increase fuel efficiency in direct injection, compression ignition (DICI) combustion engines. PPC is strongly influenced by how the fuel mixes with oxidizer, which for a given fuel is controlled mainly by (a) the injection, (b) the in-cylinder flow and (c) the geometry and dynamics of the engine. As injection timings can vary over a wide range in PPC combustion deeper knowledge of the in-cylinder flow over the whole compression stroke can improve our understanding of PPC combustion. In computational fluid dynamics (CFD) the in-cylinder flow is sometimes simplified and modeled as a solid body rotation at some time prior to injection in order to produce a realistic flow field at the moment of injection. In real engines the in-cylinder flow motion is governed by the intake manifold, the valve motion and the engine geometry.
2017-10-08
Technical Paper
2017-01-2218
Roman Varbanets, Igor V. Gritsuk, Aleksey Yeryganov
Operability and efficiency of automobiles and infrastructure of stationary power and transport significantly depends on technical condition and technical operation of internal combustion engines, mostly which are diesel engines. Expedient operation of diesel engines in processes holding a timely procedure of parameters monitoring of technical condition and identification, during the work. In the article features of diagnosing of the diesel engine with uniformity of loadings distribution between cylinders provided that of ensuring normal operating state of the fuel units and components of the main systems of the diesel are considered. Results of definition of engine power, efficiency of fuel using and observance of the main ecological restrictions depending on uniformity of distribution of loadings between cylinders are presented. Also in article the main methods of diagnosing of the diesel engine in processes of its work under operating conditions are described.
2017-10-08
Technical Paper
2017-01-2217
Fushui Liu, Ning Kang, Yikai Li, Pei Wang
The electronic unit pump system, which is widely applied to the heavy-duty diesel engine, belongs to the pulsating high pressure fuel injection system, and the fuel pressure fluctuations have an essential influence on the spray and combustion in the internal combustion engine. Pressure fluctuations are always aroused by the motion of actuators, such as the injector, so it is also an advantage for fault diagnosis and feedback control to ascertain the relationship between the pressure fluctuation and the motion of the actuator. In this study, experiments and 1D simulation were carried on to investigate the fuel pressure fluctuation characteristics and their connection to the transient motion of the needle valve in the injector.
2017-10-08
Technical Paper
2017-01-2227
Wei Guan, Vinícius Pedrozo, Hua Zhao, Zhibo Ban, Tiejian Lin
Abstract In order to meet increasingly stringent emissions standards and lower the fuel consumption, significant efforts are being made to develop high efficiency low emission internal combustion engines and after-treatment systems. In addition to the trade-off between thermal efficiency and nitrogen oxides (NOx) emissions, the conversion efficiency of the diesel aftertreatment system decreases rapidly at lower exhaust temperature, which occurs at low load operations. Thus, it is necessary to investigate and identify the appropriate combustion and engine control strategies which can lead to lower vehicle exhaust emission by keeping the engine-out NOx low and NOx aftertreament conversion efficiency high through elevated engine exhaust gas temperature (EGT). In this work, an experimental investigation has been performed using external EGR and Miller cycle achieved by delaying the intake valve closing (IVC) timing on a single cylinder heavy-duty diesel engine.
2017-10-08
Technical Paper
2017-01-2238
Ripudaman Singh, Margaret Wooldridge, Mohammad Fatouraie, George Lavoie, Travis Burch
Numerous studies have demonstrated the benefits of ethanol in increasing the thermal efficiency of gasoline-fueled spark ignition engines via the higher enthalpy of vaporization and higher knock resistance of ethanol compared with gasoline. This study expands on previous work by considering a split fuel injection strategy with a boosted direct injection spark ignition (DISI) engine fueled with E0 (100% by volume reference grade gasoline; with research octane number = 91 and motoring octane number = 83), E100 (100% by volume anhydrous ethanol), and various splash-blends of the two fuels. Experiments were performed using a production 3-cylinder Ford Ecoboost engine where two cylinders were de-activated to create a single-cylinder engine with a displacement of 0.33 L. The engine was operated over a range of loads with boosted intake manifold absolute pressure (MAP) from 1 bar to 1.5 bar absolute.
2017-10-08
Technical Paper
2017-01-2246
Ho Teng
Atkinson cycle realized with a late intake valve closing (LIVC) and Miller cycle achieved with an early intake valve closing (EIVC) have been recognized as effective approaches for improving the gasoline engine fuel economy. In both Atkinson and Miller cycles, the engine can be designed with a higher geometric compression ratio for increasing the expansion work and the effective compression ratio is governed by the intake valve close (IVC) timing for the knock control. Duration of the intake event and IVC timing affect not only the pumping loss during the gas exchange, but also have strong influences on the friction torques of the intake cams and the turbulence intensities for the in-cylinder charge motion. The latter governs duration of combustion and EGR tolerance, both of which have impacts on the engine thermal efficiency.
2017-10-08
Technical Paper
2017-01-2242
Boyuan Wang, Changpeng Liu, Zhi Wang, Li Fubai, Yingdi Wang, Yunliang Qi, Xin He, Jian-Xin Wang
A new ignition method is proposed called flame accelerated ignition, which is realized by a flame acceleration tunnel set between the spark plug and the main chamber with annular spoilers inside. The investigation of flame accelerated ignition was experimentally accomplished on both a rapid compression machine with optical accessibility and a single-cylinder heavy duty engine. In rapid compression machine study, synchronous pressure sensing and high-speed photography were used with spark ignition cases tested for comparison. The results show that the combustion process is significantly accelerated by flame acceleration ignition. The combustion duration is shortened by more than 30% under all loads compared with spark ignition. According to the optical results, the axial speed of flame outside the flame acceleration tunnel reaches at least 30 m/s and shows positive correlation with load, which is over 10 times than that of conventional flame propagation caused by spark ignition.
2017-10-08
Technical Paper
2017-01-2252
Weihua Sun, wei Du, Xuefei Dai, Xiangdong Bai, Zhiping Wu
Getting real cylinder pressure is the basis of engine combustion analysis. Because of the advantages of good thermal performance, fast response, small size, high accuracy, large range and so on, piezoelectric quartz sensor is widely used in the measurement of the cylinder pressure. But this kind of sensor can only get the dynamic cylinder pressure which may not represent the real one. In this situation, the cylinder pressure needs to be corrected by some method. It also could cause great result divergences of the combustion analysis by using different cylinder pressure correction methods. This paper aims to acquire a proper cylinder pressure correction method by carrying out the theory analysis based on ideal gas equation and experiment research of cylinder pressure on a turbocharged eight-cylinder diesel engine.
2017-10-08
Technical Paper
2017-01-2251
Lei Feng, Beiling Chen, Haifeng Liu, Mingfa Yao, Chao Geng
The flame structure and combustion characteristics of wall-impinging diesel fuel spray were investigated on a high-temperature high-pressure constant volume combustion vessel. The ambient temperature (Ta) was set to 773 K, and the wall temperature (Tw) was set to 523 K, 673 K, 773 K respectively. Three different injection pressures (Pi) of 600 bar, 1000bar, 1600bar, and two ambient pressures (Pa) of 2 MPa, 4 MPa were applied. The flame development process of wall-impinging spray was measured by high-speed photography, which was utilized to quantify the flame luminosity intensity, ignition delay, and flame geometrical parameters. The results reveal that, as the wall temperature increases, the flame luminosity intensity increases and the ignition delay decreases.
2017-10-08
Technical Paper
2017-01-2259
Tianpu Dong, Fujun Zhang, Hongli Gao, Sufei Wang, Yidong Fei
The diesel low temperature combustion(LTC) can keep high efficiency and produce low emission. It has been widely studied at home and abroad in recent years. The combustion control parameters such as injection pressure, injection timing, intake oxygen concentration, intake pressure, intake temperature and so on, have an important influence on the combustion and emission of diesel LTC. In order to realize different combustion modes and combustion mode switch of diesel engine, it is necessary to accurately control the injection parameters and intake parameters of diesel engine. In this work, the effect of intake oxygen concentration, intake pressure and intake temperature on the combustion and emission characteristics of diesel LTC were analyzed by experimental study. Combustion performance and emission characteristics such as in-cylinder pressure, temperature, heat release rate, NOx and soot emission are presented and discussed.
2017-10-08
Technical Paper
2017-01-2264
Hyun Woo Won, Alexandre Bouet, Joseph KERMANI, Florence Duffour, Simon Dosda
Recent work has demonstrated the potential of gasoline-like fuels to reduce NOx and particulate emissions when used in compression ignition engines. In this context, low RON gasoline, a refinery stream derived from the atmospheric crude oil distillation process, has been identified as a highly valuable fuel. In addition, thanks to its higher H/C ratio and energy content compared to diesel, CO2 benefits are also expected when used in such engines. In previous studies, different Cetane Number (CN) fuels have been evaluated and a CN 35 fuel has been selected. The assessment and the choice of the required engine hardware adapted to this fuel, such as the compression ratio, bowl pattern and nozzle design have been performed on a single cylinder compression-ignition engine. The purpose of this paper is to assess different airpath and after treatment system (ATS) definitions to maximize the potential of a low-RON gasoline fuel running on a multi-cylinder compression ignition engine.
2017-10-08
Technical Paper
2017-01-2277
Xiao Peng, Han Wu, Chia-Fon Lee, Qianbo sun, Fushui Liu
Methanol has been regarded as a potential transportation fuel due to its advanced combustion characteristics and flexible source. However, it is suffering from misfire and high HC emissions problems under cold start and low load conditions either on methanol SI engine or on methanol/diesel dual fuel engine. Hydrogen is a potential addition that can enhance the combustion of methanol due to its high flammability and combustion stability. In the current work, the effect of hydrogen ratio on the laminar flame characteristics of hydrogen-methanol-air mixture under varied equivalence ratios was investigated on a constant volume combustion chamber system coupled with a schlieren setup. A high-speed camera, set at 512X512 pixel and 10000 fps, was used to record the instantaneous images of the flame front during propagating.
2017-10-08
Technical Paper
2017-01-2276
Furong Lin, Fan Zhang
In view of engine engineering, combustion instability are widely presented in many engines, such as liquid rocket engine, ramjet engine, scramjet engine and SI(spark-ignition) engine, which is harmful to normal operation of engines and even damage the engine in an instant. In this paper, three dimensional numerical simulation of methane premixed gas combustion in a backward-facing step is investigated in an atmosphere pressure. The large eddy simulation and a mixing method of the eddy-dissipation/Arrhenius are used for turbulent combustion model, The two-step methane global reaction is employed for reaction. The effects of different methane premixed gas inlet velocities on backward-facing step combustion stability are studied. When the premixed gas inlet velocity is in high value, the premixed flow can’t be ignited quickly. There is large vorticity near the step and vortex will take the unburned premixed gas to the high-temperature reaction zone.
2017-10-08
Technical Paper
2017-01-2280
Yuzuru Nada, So Morimoto, Yoshiyuki Kidoguchi, Ryu Kaya, Hideaki Nakano, Shinichi Kobayashi
In our previous studies, we have developed natural gas engines operating under lean conditions to improve thermal efficiency and emission characteristics. We applied a sub-chamber injection system to our engines, in which natural gas is directly injected into a combustion sub-chamber in order to completely separate stoichiometric mixture in the sub-chamber from ultra-lean mixture in the main chamber. The results obtained from engine tests demonstrated excellent performance of our engines in view point of efficiency and NOx emissions. However, we have poor knowledge of mixture distributions in the combustion chambers to understand the mechanism of the improvements. The aim of this paper is to clarify the mixture formation in combustion chambers by means of numerical simulations in the combustion chamber with and without the sub-chamber at a variety of operating conditions.
2017-10-08
Technical Paper
2017-01-2297
Thomas Dubois, Lidwine ABIAD, Pauline CAINE
As it is the case for Diesel engines, the Gasoline Direct Injection engines are using higher and higher injection pressures. The state of the art GDI engines are currently using injection pressure as high as 500 bar. A lot of work is also currently ongoing on Gasoline Compression Ignition (GCI) engines which use even higher injection pressure (above 1 000 bar). A high injection pressure means that a high pressure pump has to be used and so, proper lubricity has to be brought by the fuel. In the mean time the use of biofuels is increasing and several studies have shown the positive impact of ethanol on the fuel consumption of gasoline engines mainly thru an octane number effect. For all these reasons, it seems important to evaluate the impact of ethanol on the lubricity of gasoline as well as on the response of lubricity additives that may be required in a medium-term future to provide gasoline enough lubricity to ensure the operability of these new engines.
2017-10-08
Technical Paper
2017-01-2301
Hongli Gao, Fujun Zhang, Wenwen Zeng, Tianpu Dong, Zhengkai Wang
Abstract:The electronic control of direct injection fuel system,which could improve engine fuel efficiency, dynamics and engine emission performance through good atomization, precise control of fuel injection time and improvement of oil-gas mixture, is the key technology to achieve the stratified combustion and lean combustion. In this paper, a direct injection injector that based on voice coil motor was designed aiming at the technical characteristics of one 800cc two-stroke camless engine. Prior to a one - dimensional simulation model of injector was established by AMEsim and the maximal fuel injection demand was met via the optimization of the main parameters of the injector, the structure of the voice coil motor was optimized by magnetic equivalent circuit method. After that, the maximal flow rate of the injector was verified by the injector bench test while the atomization effect of the injector was verified by using a high-speed camera.
2017-10-08
Technical Paper
2017-01-2320
George S. Dodos, Chrysovalanti E. Tsesmeli, Iraklis Zahos Siagos, Theodora Tyrovola, Dimitrios Karonis, Fanourios Zannikos
FAME is the most common renewable component of conventional automotive diesel fuel offering environmental benefits when it is used in internal combustion engines. Despite the advantages, biodiesel is more susceptible to oxidative deterioration and due to its chemical composition as well as its high affinity to water, is considered to be a favorable substrate for microorganisms. On the other hand, apart from biodiesel, alcohols are considered to be promising substitutes to conventional diesel fuel because they could offer higher oxygen concentration leading to better combustion characteristics and lower exhaust emissions. In specific, according to the literature, n-butanol is a renewable alcohol demonstrating better blending capabilities and properties when it is added in diesel fuel, as its composition is closer to conventional fuel, compared to ethanol in example.
2017-10-08
Technical Paper
2017-01-2324
Nagendra Singh
Biodiesel is an alternate fuel can be use diesel engine with blending in percentage .Bio diesel is created by chemically reacting fatty acids and alcohol by combining vegetable oil with methanol in the presence of a catalyst. Biodiesel is much more suitable for use as an engine fuel having low viscosity however reliability challenges will be there like Low engine power, Low Fuel efficiency, High engine deposits , clogging of fuel and oil filter, High Nox, Fuel property Stability, FIE parts wear , Oil slugging and High maintainability cost etc . There are various experiment, test and validation activity carried out while developments of Bio diesel engine and results were compiled.
2017-10-08
Technical Paper
2017-01-2321
Timothy H. Lee, Gang Li, Han Wu, Tonghun Lee, Alan Hansen
Bio-butanol has been considered as a promising alternative fuel for transportation due to its advantageous physical and chemical properties, but the high recovery and dehydration cost reduced its competitiveness in the fuel market. In order to achieve the bio-fuel advantage, the current work tried to apply and evaluate the upstream products of bio-butanol, Isopropanol-Butanol-Ethanol (IBE). These mixtures are obtained by ABE fermentation and IBE fermentation respectively, as alternative diesel fuel. Isopropanol-Butanol-Ethanol (IBE) is an intermediate product in the IBE fermentation process for producing bio-butanol. The study was carried out in an AVL 5402 single-cylinder diesel engine fueled by IBE-Diesel, ABE-Diesel and neat diesel. During the experiments, the engine speed, engine loads, and injection timings were varied. The results showed that with the addition of IBE in diesel fuel, the engine can still operate smoothly with a set pilot injection.
2017-10-08
Technical Paper
2017-01-2305
Jun Yamauchi, PengBo Dong, Keiya Nishida, Youichi Ogata
With the aim of improving engine performance, recent trend of fuel injection nozzle design followed by engineers and researchers is focusing on more efficient fuel break up, atomization, and fuel evaporation. Therefore, it is crucial to characterize the effect of nozzle geometric design and the injection condition on fuel internal flow dynamics and the consequent fuel-air mixture properties. In this study, the internal flow and spray characteristics generated by the practical multi-hole nozzles with different nozzle hole diameter and injection pressure were investigated in conjunction with a series of computational and experimental methods. Specifically, the CFD commercial code was used to predict the internal flow variation under the different nozzle hole diameter and injection pressure,and the high-speed video observation method was applied to visualize the spray evolution processes under the non-evaporating condition.
2017-10-08
Technical Paper
2017-01-2336
Tanjin He, Hao-ye Liu, Yingdi Wang, Boyuan Wang, Hui Liu, Zhi Wang
Polyoxymethylene Dimethyl Ether (PODEn) is a promising green additive to diesel fuel, owing to the unique chemical structure (CH3O[CH2O]nCH3, n≥2) and high cetane number. Together with the general wide-distillation fuel (WDF), which has an attractive potential to reduce the cost of production of vehicle fuel, the oxygenated WDF with PODEn can help achieve a high efficiency and low emissions of soot, NOx, HC, and CO simultaneously. In this paper, the first detailed reaction mechanism (225 species, 1082 reactions) which can describe the ignition characteristics of PODE1 and PODE3 at low temperature was developed.
2017-10-08
Technical Paper
2017-01-2333
Marcos Gutierrez, Juan Iniguez, Andres Castillo, Gorky Reyes
The aim for cleaner and more efficient energy from the internal combustion engines makes necessary to ensure the conditions for the exploitation of alternative fuels. The vibrations on engines are primarily understood as effects of mechanical failures, but the engine vibration is subject of the fuel combustion effects too. This effects will depend on the fuel type and its capacity to be burned. The vibrations of a diesel engine were measured and analyzed with a frequency spectrum calculated with Fast Fourier Transforms. The engine was operated with a fuel blend from 10 % recycled lubricating oil with 90% diesel as well as only diesel. It was found the engine operation with this fuel blend has a lower vibration level in comparison with the use of pure diesel. The goal of this research is to determine the properties of the fuel blend, which provides more stability to the engine by means of vibrations reduction.
2017-10-08
Technical Paper
2017-01-2350
Chalermwut Wongtaewan, Umaporn Wongjareonpanit, Komkrit Sivara, Ken Hashimoto, Yoichiro Nakamura
In Thailand, most heavy-duty trucks were equipped with diesel engine, while a small portion was equipped with compressed natural gas (CNG) engine. However, in the past few years the number of CNG fuel trucks in Thailand has increased significantly due to the cheaper cost of CNG. In general, the emphasis of heavy-duty diesel engine oil performance is on piston cleanliness and soot handling properties, while thermal and anti-oxidation properties are most critical for CNG engine oil performance. For truck fleet owners who operate both types of trucks, using the inappropriate oil that is not fit-for-purpose can adversely affect engine performance and reduce engine service lifespan under prolonged usage. A novel CNG/diesel engine oil has developed by PTT to meet both JASO DH-2 performance for heavy-duty diesel engine oils and OEM requirements for CNG engine oils.
2017-10-08
Technical Paper
2017-01-2344
Robert Taylor, Hua Hu, Carl Stow, Robert Mainwaring, Scott Rappaport, Tony Davenport, Sarah Remmert
Future scenarios prepared by Shell anticipate that worldwide energy demand will approximately double by 2050, whilst at the same time, CO2 emissions need to be halved. Therefore, there is great pressure on improving efficiency of all machines, and clearly there is great focus on improving the fuel efficiency of passenger cars. The use of downsized, boosted, gasoline engines, can lead to exceptional fuel economy, and on a well-to-wheels basis, can give similar CO2 emissions to electric vehicles (depending, of course, on how the electricity is generated). A study is reported on a low weight Shell concept car, equipped with a three-cylinder 0.6 litre gasoline engine, which has achieved over 100 miles per imperial gallon, in real world driving conditions.
2017-10-08
Technical Paper
2017-01-2388
Ahmad Khalfan, Gordon Andrews, Hu Li
The emissions from vehicles in real world driving are of current concern, as they are often higher than on legislated test cycles and this may explain why air quality in cities has not improved in proportion to the reduction in automotive emissions. This has led to the Real Driving Emissions (RDE) legislation in Europe. RDE involves journeys of about 90km with roughly equal proportion of urban, rural and motorway driving. However, air quality exceedances occur in cities with urban congested traffic driving as the main source of the emissions that deteriorate the air quality. Thus the emissions measured on RDE journeys may not be relevant to air quality in cities. A Temet FTIR and Horiba exhaust mass flow measurement system was used for the mass emissions measurements in a Euro 4 SI vehicle. A 5km urban journey on a very congested road was undertaken 29 times at various times so that different traffic congestion was encountered.
Viewing 1 to 30 of 110627