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2016-11-08
Technical Paper
2016-32-0072
Fino Scholl, Paul Gerisch, Denis Neher, Maurice Kettner, Thorsten Langhorst, Thomas Koch, Markus Klaissle
One promising alternative for meeting stringent NOx limits while attaining high engine efficiency in lean-burn operation are NOx storage catalysts (NSC), an established technology in passenger car aftertreatment systems. For this reason, a NSC system for a stationary single-cylinder CHP gas engine with a rated electric power of 5.5 kW comprising series automotive parts was developed. Main aim of the work presented in this paper was maximising NOx conversion performance and determining the overall potential of NSC aftertreatment with regard to min-NOx operation. The experiments showed that both NOx storage and reduction are highly sensitive to exhaust gas temperature and purge time. While NOx adsorption rate peaks at a NSC inlet temperature of around 290 °C, higher temperatures are beneficial for a fast desorption during the regeneration phase. Combining a relatively large catalyst (1.9 l) with a small exhaust gas mass flow leads to a low space velocity inside the NSC.
2016-11-08
Technical Paper
2016-32-0055
Carlos Alberto Romero, Luz Adriana Mejia, Yamid Carranza
A Design of experiments methodology was carried out to investigate the effects of compression ratio, cylinder head material, and fuel composition on the engine speed, fuel consumption, warm-up time, and emissions of a carbureted single cylinder air-cooled spark ignited engine. The work presented here is aimed at finding out the sensitivity of engine responses, as well as the optimal combination among the aforementioned parameters. To accomplish this task two cylinder heads, one made of aluminum and the second one of cast iron, were manufactured; an antechamber-type adapter for the spark plug to modify the combustion chamber volume was used, and two ethanol/gasoline blends containing 10 and 20 volume percent ethanol were prepared. Engine performance was evaluated based on the changes in engine speed at idle conditions. Regarding the exhaust gas emissions, the concentrations of CO2, CO, and HC were recorded.
2016-11-08
Technical Paper
2016-32-0067
Akira Miyamoto, Kenji Inaba, Yukie Ishizawa, Manami Sato, Rei Komuro, Masashi Sato, Ryo Sato, Patrick Bonnaud, Ryuji Miura, Ai Suzuki, Naoto Miyamoto, Nozomu Hatakeyama, Masanori Hariyama
On the basis of extensive experimental works about heterogeneous catalysts, the authors have tried to develop a variety of software for the design of automotive catalysts such as ultra-accelerated quantum molecular dynamics (UA-QCMD) which is 10,000,000 times faster than the conventional first principles molecular dynamics(1-3), mesoscopic modeling software for supported catalysts(POCO2), and mesoscopic sintering simulator SINTA(4,5) to calculate sintering behavior of both precious metal such as Pt, Pd, Rh and support such as Al2O3, ZrO2, CeO2, or CeO2-ZrO2 We also have integrated these softwares to develop multiscale, multiphysics simulator for the design of automotive catalysts. The method was confirmed to be effective for a variety of important catalytic reactions in the automotive emission control.
2016-11-08
Technical Paper
2016-32-0068
FNU Joel Prince Lobo, James Howard Lee, Eric Oswald, Spenser Lionetti, Robert Garrick
The performance and exhaust emissions of a commercially available, propane fueled, air cooled engine with Electronic Fuel Injection (EFI) were investigated by varying relative Air to Fuel Ratio (λ), spark timing, and Compression Ratio (CR). Varying λ and spark timing was accomplished by modifying the EFI system using TechniCAL Industries’ engine development software. The CR was varied through using pistons with different bowl sizes. Strong relationships were recorded between λ and spark timing and the resulting effect these parameters have on engine performance and emissions. Lean operation (λ > 1) has the potential to significantly reduce NOx production (3,000 PPM down to 300 PPM). Unfortunately, it also reduces engine performance by up to an order of magnitude (31 Nm down to 3 Nm).
2016-11-08
Technical Paper
2016-32-0093
Denis Neher, Fino Scholl, Maurice Kettner, Danny Schwarz, Markus Klaissle, Blanca Giménez Olavarria PhD
Combustion temperature represents the driving parameter for NOx emissions. Lean burn operation allows engines to reduce combustion temperature due to relatively high heat capacity of the excess air. Lean operating cogeneration engines, however, need additionally to retard ignition timing to meet NOx emission standards. The late combustion phasing leads to a further deviation from the ideal Otto cycle, causing losses in engine efficiency. When substituting a part of the excess air with exhaust gas, heat capacity increases. Combustion phasing can be advanced, resulting in a thermodynamically more favourable heat release. As a result, engine efficiency improves without increasing NOx emissions. In this work, the effect of replacing a part of excess air with exhaust gas was investigated first in a constant volume combustion chamber. It enabled to analyse the influence of the exhaust gas under steady initial conditions for several relative air-fuel ratios (λ = 1.3…1.7).
2016-11-08
Technical Paper
2016-32-0066
P A Lakshminarayanan, S. Aswin
ABSTRACT Particulates from diesel engine consisting of particles of carbon, sulphates, oil, fuel and water are measured by filtering a sample diluted in a partial or full flow tunnel according to strict standards and weighing them. However, these methods suffer from high initial and running costs. On the other hand, filter smoke meters measure the light reflected from a filter paper through which a known volume of exhaust gas is passed and Opacity meters measure light absorbed by a standard column of exhaust. They measure visible black smoke easily at reasonable expenditure. Today, these simple instruments are highly developed to control measurement noise, resolution and repeatability, and can be used to estimate carbon soot precisely.
2016-11-08
Technical Paper
2016-32-0069
Indranil Brahma, Cristobal Manzanares, Rob Jennings, Odinmma Ofili, Matthew Campbell, Abishek Raghavan, Daniel Johnson, Peter Stryker
Non-volatile particle number distributions from a single cylinder industrial diesel engine were measured at several operating conditions spanning the torque curve. The effect of increasing the air-fuel ratio by injecting compressed shop air at various boost pressures was also investigated. A bi-modal distribution separated at approximately 20 nm was observed for most operating conditions. Depending on operating condition, the engine produced between 1014 to 1015 particles per kW-hr. Energy specific particle number emissions (per kW-hr) were seen to be strongly dependent on speed and load. Minimum emissions occurred at intermediate speeds and loads. Particles below 20 nm increased with increasing air-fuel ratio, while the opposite trend was observed for particles greater than 20 nm. Variation in total particle surface and total particle volume followed the same trends as the particles from the larger mode.
2016-11-08
Technical Paper
2016-32-0071
Koji Ueno, Hiroyuki Horimura, Akiko Iwasa, Yuji Kurasawa, Pascaline tran, Ye Liu
Motorcycles are one of the major modes of transportation globally, and further expansion of motorcycle demand and usage is expected to continue because of population growth and individual income increase, in particular in emerging countries. At the same time, approach to critical environmental issues, such as escalation of air pollution, becomes more important challenge and this trend accelerates tightening of motorcycle emission regulation globally. In accordance with this, responding to social needs and minimizing the impact on air pollution while enhancing features of motorcycles, such as drive performance, convenience, and price attractiveness are our mission as a manufacture. Platinum group metals (PGMs) such as platinum, palladium and rhodium are commonly used for automotive and motorcycle catalysts. One of catalyst researchers’ dream is ultimately to develop catalyst without using such PGMs that are precious and costly resources.
2016-11-08
Technical Paper
2016-32-0012
Zhimin Lin, Kotaro Takeda, Yuki Yoshida, Akira Iijima, Hideo Shoji
Homogeneous Charge Compression Ignition (HCCI) combustion have attracted much attention as a high efficiency and clean combustion system. However, it is difficult to control the ignition timing because there are no a physical means of ignition. In addition, it is difficult to expand the operating range due to the occurrence of misfiring at low loads and the occurrence of rapid combustion (HCCI knocking) accompanied by in-cylinder pressure oscillations at high loads. Therefore, it is important to reduce the pressure oscillations of HCCI combustion knocking for expanding the operating range to the high load region. This study focused on the rapid combustion in HCCI. A primary reference fuel (0 RON) was used as the test fuel. The influence of external exhaust gas recirculation (cooled EGR) on HCCI knocking was investigated. HCCI combustion flame behavior with pressure oscillations were visualized by using a two-stroke engine that allowed visualization of the entire bore area.
2016-11-08
Technical Paper
2016-32-0063
Marc Cyrill Besch, April Nicole Covington, Derek Johnson, Nathan Fowler, Robert Heltzel
The aim of this investigation was to improve understanding and quantify the impact of exhaust gas recirculation (EGR) as an emissions control measure onto cyclic variability of a small-bore, single-cylinder, diesel-fueled compression-ignition (CI) power generation unit. Of special interest were how cycle-to-cycle variations of the CI engine affect steady-state voltage deviations and frequency bandwidths. Furthermore, the study strived to elucidate the impact of EGR addition onto combustion parameters, as well as gaseous and particle phase emissions along with fuel consumption. The power generation unit was operated over five discrete steady-state test modes, representative of nominal 0, 25, 50, 75, and 100% engine load (i.e. 0-484kPa BMEP), by absorbing electrical power via a resistive load bank. The engine was equipped with a passive EGR system that directly connected the exhaust and intake runners through a 4mm diameter passage.
2016-11-08
Technical Paper
2016-32-0070
Toyofumi Tsuda, Kazuya Miura, Akio Hikasa, Keiji Hosoi, Fumikazu Kimata
Automotive catalyst has to have good durability, i.e. has to keep sufficient catalytic performance even after thermal degradation, therefore large amounts of PGMs such as Pt, Pd, and Rh, should be loaded on the catalyst substrate. Exhaust gas heat deteriorates catalyst due to sintering of the PGM particles and decrease of the active surface area. It is important to reduce PGM load, therefore many researchers have investigated to satisfy both PGM  load reduction and enough durability by using metal / support interactions, or controlling the nano-structure of metal particles. We found that Pt ions form platinum-hydrate cluster in hexahydroxyplatinate(IV) (Pt(OH)6・H2O) nitric acid solution, and the Pt-hydrate cluster size can be controlled by Pt and nitric acid concentration, and solution temperature.
2016-11-08
Technical Paper
2016-32-0065
Yoshinori Nakao, Yota Sakurai, Atsushi Hisano, Masahito Saitou, Masahide Kazari, Takahito Murase, Kozo Suzuki
Euro5 is a new regulation on exhaust gases from motorcycles and will be implemented in 2020. Total Hydrocarbon (THC) is among the regulated exhaust gases. This paper is focused on the emission behavior of THC. In the transient state at engine start, port injection from the upstream makes it difficult to control the amount of cylinder fuel supply for each cycle. This is one of the main reasons for THC emission. In this study, changing the fuel injection specifications could lead to THC emission reduction. The THC emission behavior was investigated. A change in the position of injection from upstream to downstream could determine the amount of the cylinder fuel supply at the engine start. This change could eliminate misfire, thereby reducing THC emission. However, the diameters of the sprayed particles that flow directly into the cylinders are large. Hence, only changing the injection position to downstream could have a negative effect at engine start.
2016-11-08
Technical Paper
2016-32-0076
Rahul Sharma, Srikanth setlur, Satish vemuri, C Subramoniam
The effect of ethanol blended gasoline fuels on Vehicular emissions was investigated in a spark ignited single cylinder carbureted vehicle meeting BSIII emission norms. The effect of fuel blended with 10(E10) & 20(E20) by percentage ethanol by volume; was studied on Type 1 vehicular mass emissions in World Harmonized Motorcycle Test Cycle (WMTC) as well as Indian drive cycle (IDC). These cycles are simulation of real driving conditions. The addition of ethanol to gasoline fuel enhances the octane number of the blended fuels and increases leaning effect. It has been observed that in IDC, addition of ethanol reduces CO up to 41%, while THC emissions decreases by 9%. Tail pipe NOx reduces up to 12%. In WMTC Cycle, the CO reduction is up to 32%, THC emission is increased by 30%. NOx emissions on WMTC cycle decrease with the use of E10 by 6% while increase with the use of E20 by 7%. The blended fuels decrease fuel economy by 6~8% on these cycles owing to their lower calorific value
2016-11-08
Technical Paper
2016-32-0075
Srikanth setlur, Satish vemuri, C Subramoniam, Rahul Sharma
In a diverse country like India, quality of fuel varies from one region to another region. This study explores the effect of various ethanol fuel mix on a single cylinder Closed loop fuel injected SI vehicle which is EuroIII complaint. Fuels blended with 10(E10) & 20(E20) percentage of ethanol by volume; were taken up to study their effect on vehicular mass emissions in World Harmonized Motorcycle Test Cycle (WMTC).The cycle is a simulation to real world driving conditions. In WMTC Cycle, maximum CO emissions were obtained with E10 fuel which showed an increase of 13%. THC emissions decreased by 10% & NOx emissions remained the same when the ethanol percentage increases. Fuel economy decreases by 5% with use of E20 on the cycle. Further this paper investigates the various factors like AFR, CAT light off etc, which are responsible for change in tail pipe emissions.
2016-10-17
Technical Paper
2016-01-2319
Kihong Kim, Rahul Mital, Takehiro Higuchi
In the previous research1), the authors discovered that the sudden pressure increase phenomenon in diesel particulate filter (DPF) was a result of soot collapse inside DPF channels. The proposed hypothesize for soot collapse was a combination of factors such as passive regeneration, high humidity, extended soak period, high soot loading and high exhaust flow rate. The passive regeneration due to in-situ NO2 and high humidity caused the straw like soot deposited inside DPF channels to take a concave shape making the collapse easier during high vehicle acceleration. It was shown that even if one of these factor was missing, the undesirable soot collapse and subsequent back pressure increase did not occur. Currently, one of the very popular NOx reduction technologies is the Selective Catalytic Reduction (SCR) on Filter which does not have any precious group metal (PGM) in the washcoat.
2016-10-17
Technical Paper
2016-01-2321
Zahra Nazarpoor, Steve Golden, Maxime Launois, Sen Kitazumi, Dianyong Xie, Campbell McConnell
The stricter regulatory standards are continuously adopted worldwide to control heavy duty emissions, and on the other hand fuel economy requirements lowered significantly the exhaust temperatures; net result a significant increase in PGM usage with current DOC technology. In this regard, CDTi is mainly focused on design and development of synergized precious metal (SPGM) in which ultra-low PGM is synergized with Mixed Metal Oxide (MMO) to achieve highly beneficial emission performance improvements. The presence of MMO in SPGM is responsible for NO oxidation to NO2 which is critical for the passive regeneration of the downstream filter and SCR function. This paper presents an initial study outlining the development of MMOs for application in modern DOC and addresses some specific challenges underlying this application. Lab and flow reactor data in this study showed SPGM DOCs thermal resistance and sulfur poisoning resistance.
2016-10-17
Technical Paper
2016-01-2323
Hiroki Nakayama, Yasuharu Kanno, Makoto Nagata, Xiaolai Zheng
Recently, the regulations of exhaust gases for gasoline vehicles are become severe. To meet the regulation of exhaust gases, TWC catalysts with precious metal group were used. On the other hands, It is required the reduction the amounts of precious metal group (Pt, Pd, Rh) of TWC from a point of shortage of resource of PGM and cost issue. Conventional TWC system were composed closed couple catalyst and under floor catalyst. The closed couple TWC promoted the HC/CO oxidation and NOx reduction by CO. The under floor TWC mainly promoted the NOx reduction by CO. In this reports, to reduce the PGM amounts, cc-TWC with PGM, UF-Non PGM system were studied. Non-PGM catalyst has been developed for a gasoline combustion engine exhaust gas treatment. The after-treatment system is composed of PGM based closed couple catalyst, cc-TWC, and non-PGM catalyst in under flower position, UF-non-PGM. This UF-non-PGM is composed of Ni/CeO2 bottom layer and Zeolite based NH3-SCR top layer.
2016-10-17
Technical Paper
2016-01-2182
Olivier Laget, Louis-Marie Malbec, Julian kashdan, Nicolas Dronniou, Romain boissard, Patrick Gastaldi
The accumulation of particulate matter in lubricant oil has become an issue in Diesel engines where large amounts of Exhaust Gas Recirculation (EGR) are used at medium to high load operating conditions. Indeed, the accumulation of particulate matter in the engine oil can alter its lubricant properties resulting in mechanical durability issues or TCO increase due to shortened servicing intervals. It is therefore important to gain an improved understanding of the underlying mechanisms that are responsible for this accumulation of particulate matter in the lubricating oil, and ultimately provide design guidelines to help limit this phenomenon. The present study presents the development and validation of experimental and numerical tools used to investigate this phenomenon.
2016-10-17
Technical Paper
2016-01-2285
Chun Guan, Xinling Li, Zhuyue Zhuang, Zhen Huang
In the present study, the effects of oxygenated fuels on particulate-phase organic pollutants including n-alkanes, polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (oxy-PAHs) were investigated on a diesel engine test bench w/o and with a particle oxidation catalyst (POC) device. Two kinds of oxygenated fuels with different oxygenated functional groups, that are biodiesel and ethanol, were selected as the target fuels to be blended with diesel by various volume percentages. POC performance was also studied to further demonstrate the effect of aftertreatments on diesel engine emissions. The results indicated that diesel-biodiesel (DB) blends presented a good linearship between alkanes suppression and blended ratios, while diesel-biodiesel-ethanol (DBE) blends only presented a better suppression on alkanes at a lower blended ratio. Meanwhile, both DB and DBE blends presented an effective suppression on particulate-phase PAHs.
2016-10-17
Technical Paper
2016-01-2185
Jialin Liu, Hu Wang, Zunqing Zheng, Zeyu Zou, Mingfa Yao
In this work, both the ‘SCR-only’ and ‘EGR+SCR’ technical routes are compared and evaluated after the optimizations of both injection strategy and turbocharging system over the World Harmonized Stationary Cycle (WHSC) in a heavy duty diesel engine. Moreover, the emissions and fuel economy performance of different turbocharging systems, including wastegate turbocharger (WGT), variable geometry turbocharger (VGT), two-stage fixed geometry turbocharger (WGT+FGT) and two-stage variable geometry turbocharger (VGT+FGT), are investigated over a wide EGR range. The NOx reduction methods and EGR control strategies for different turbocharger systems are proposed to improve the fuel economy. The requirement of turbocharging system at various NOx emissions and their potential to meet future stringent emission regulations are also discussed in this paper.
2016-10-17
Technical Paper
2016-01-2249
Akash Gangwar, Abhinav Bhardawaj, Ramesh Singh, Naveen Kumar
Enhancement of combustion behavior of conventional liquid fuel using nanoscale materials of different properties is an imaginative and futuristic topic. This experiment is aimed to evaluate the performance and emission characteristics of a diesel engine when lade with nanoparticles of Cu-Zn alloy. The previous work reported the effect of metal/metal oxide or heterogeneous mixture of two or more particles; less work had been taken to analyze the homogeneous mixture of metals. This paper includes fuel properties such as density, kinematic viscosity, calorific value and performance measures like brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and emission analysis of NOx, CO, CO2, HC. For the same solid concentration, nano-fuel is compared with base fuel at different engine loads; and its effect when lade at different concentrations.
2016-10-17
Technical Paper
2016-01-2314
Wanyu Sun, Shufen Wang, Yue Huang, Lei Guo, Hongzhen Li, Zhangtao Yao
The possible NOx and soot limits that a conventional diesel engine could meet without the assistance of after-treatment system were investigated on an engineering application level. A methodology combining both experiment and CFD simulation was used to judge favorable and unfavorable effects of various in-cylinder strategies quantitatively. These strategies or factors include exhaust gas recirculation (EGR), fuel injection timing and duration, intake valve closure (IVC) timing, combustion chamber and turbocharger, etc. Interactions among these strategies were paid special attention. Two steps were proposed based on the analysis. The first step would shift the NOx-soot trade-off curve closer to low emission level regions via optimization of injection strategy and combustion chamber geometry. As a result, soot could be reduced by 20% ~ 30% while NOx could be maintained at the same level.
2016-10-17
Technical Paper
2016-01-2288
Sam Shamun, Mengqin Shen, Bengt Johansson, Martin Tuner, Joakim Pagels, Anders Gudmundsson, Per Tunestal
The focus has recently been directed towards the engine out soot from Diesel engines. Running the engine in PPC mode has a proven tendency of reducing these emissions significantly. In addition to combustion strategy, several studies have suggested that using alcohol fuels will aid in reducing soot emissions to ultra-low levels. This study analyzes and compares the characteristics of PM emissions from naphtha gasoline PPC, ethanol PPC, methanol PPC and methanol diffusion combustion in terms of soot mass concentration, particle size and distribution in a single cylinder Scania D13 engine, while varying the intake O2. Intake temperature and injection pressure sweeps were also conducted. The fuels emitting the highest amount of particles were gasoline followed by methanol. The two alcohols tested emitted nucleation mode particles only, whereas gasoline emitted accumulation mode particles as well.
2016-10-17
Technical Paper
2016-01-2166
Ahfaz Ahmed, Muhammad Waqas, Nimal Naser, Eshan Singh, William Roberts, Sukho Chung, Mani Sarathy
Commercial gasoline fuels contain hundreds of different hydrocarbons, yet despite their dissimilarity in composition they often demonstrate similar octane ratings. It is of fundamental interest to study differences arising in combustion performance of such fuels, specifically fuels have varying physical properties. This investigation is needed to interpret differences in combustion behavior of gasolines showing similar knocking character in a cooperative fuel research engine, but demonstrating different attributes in a direct injection spark ignition (DISI) engines due to the enhanced effects of fuel properties To investigate this scenario two FACE (Fuels for advanced combustion engines) gasolines, FACE F and FACE G with similar Research and Motor octane but differing physical and chemical properties were studied in a DISI engines.
2016-10-17
Technical Paper
2016-01-2183
Yann Gallo, Zheming Li, Mattias Richter, Oivind Andersson
Soot formation and soot oxidation are the two competing processes governing soot emissions from Diesel engines. Previous studies have been showing a poor correlation between soot formation rate and soot emissions. This article presents a systematic study of a number of parameters affecting soot oxidation rate and the correlation with soot emissions. An optical heavy-duty engine has been used in conjunction with a laser extinction setup in order to collect time resolved data of the soot concentration in the cylinder during the expansion phase. Laser extinction is measured using a red (685nm) laser beam, which is sent vertically through the cylinder. This wavelength was chosen long enough to minimize absorption interference from polycyclic aromatic hydrocarbons, while still in the visible regime. It is modulated in order to produce 10 pulses per crank angle degree.
2016-10-17
Technical Paper
2016-01-2187
Haifeng Liu, Huixiang Zhang, Hu Wang, Xian Zou, Mingfa Yao
The combustion in low-speed two-stroke marine diesel engines can be characterized as large spatial and temporal scales combustion. One of the most effective measures to reduce NOx emissions is to reduce the local maximum combustion temperature. In the current study, multi-dimensional numerical simulations have been conducted to explore the potential of Miller cycle, high compression ratio coupled with EGR (Exhaust Gas Recirculation) and WEF (water emulsified fuel) to improve the trade-off relationship of NOx-ISFC (indicated specific fuel consumption) in a low-speed two-stroke marine engine. The results show that the EGR ratio could be reduced combined with WEF to meet the Tier III emission regulation. The penalty on fuel consumption with EGR and WEF could be offset by Miller cycle and high geometric compression ratio.
2016-10-17
Technical Paper
2016-01-2181
Yong Qian, Yahui Zhang, Liang Yu, Zhen Huang, Xing-cai Lu
In this paper, an experimental study based on a modified single cylinder diesel oil engine has been conducted to study the effects of diesel oil blending different iso-alkanes on the combustion and emissions. Iso-octane, iso-dodecane and 2,2,4,4,6,8,8-Heptamethylnonane (HMN) were chosen as iso-alkanes. During the experiment, the direct injection timing was kept at 7 oCA BTDC, and the injection pressure was maintained at 120MPa. The study found that after blending iso-alkanes, the changes of fuel physical properties have significant effects on the heat release phase under low load. However, the effects are weakened gradually with the improvement of loads. The peak value of heat release curves and the maximum pressure rising rate gradually increase with the improvement of loads after mixing with iso-alkanes.
2016-10-17
Technical Paper
2016-01-2320
Tsuyoshi Asako, Ryuji Kai, Tetsuo Toyoshima, Claus Vogt, Shogo Hirose, Shiori Nakao
Ammonia Selective Catalytic Reduction (SCR) is adapted for a variety of applications to control NOx in diesel engine emission. Most commonly used catalyst for SCR in established markets is Cu-Zeolite due to excellent NOx conversion and thermal durability. However, most applications in emerging markets and certain applications in established markets utilize Vanadia SCR. The operating temperature is typically maintained below 550C to avoid vanadium sublimation due to passive regeneration of diesel particulate filter (DPF) or eliminating DPF from aftertreatment system. For DPF-less system, particulate matter (PM) standard is achievable without DPF depending on engine tuning. Further improvement of Vanadia SCR durability and NOx conversion at low exhaust gas temperatures will be required in consideration of future emission standards.
2016-10-17
Technical Paper
2016-01-2351
Kotaro Tanaka, Kazuki Hiroki, Tomoki Kikuchi, Mitsuru Konno, Mitsuharu Oguma
Exhaust gas recirculation (EGR) is widely used in diesel engines to reduce nitrogen oxide (NOx) emissions. However, a kind of lacquer is formed on the EGR valve or EGR cooler because of the particulate matters and other components present in diesel exhaust, which are serious problems. In this study, the mechanism of the lacquer deposition has been investigated using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectrometer, which allows for in situ measurements of the surface of the depositing lacquer. Scanning electron microscope (SEM) was also used to perform detail observation of the lacquer. Deposition of temperature-dependent lacquers was evaluated by varying the temperature of a diamond prism between 353 K and 393 K in ATR-FTIR that was set to a custom-built sample line, which branched off from the exhaust pipe of the diesel engine.
2016-10-17
Technical Paper
2016-01-2174
Reza Golzari, Yuanping Li, Hua Zhao
As the emission regulations for internal combustion engines are becoming increasingly stringent, different solutions have been researched and developed, such as downsizing combined with single and multistage boosting (turbocharging and/or supercharging), dual injection and fuelling systems, variable valve timing and lift devices, variable compression and expansion ratio using Miller and Atkinson cycles. The aim of these systems is to improve the in-cylinder mixture quality and therefore enhance the combustion which ultimately increases thermal efficiency and fuel economy while lowering the emissions. This paper describes the effects of dual injection systems on combustion, efficiency and emissions of a downsized single cylinder gasoline direct injection spark ignited (DISI) engine equipped with variable cam phasing on both the intake and exhaust cams.
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