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Viewing 271 to 300 of 21875
2016-11-08
Journal Article
2016-32-0065
Yoshinori Nakao, Yota Sakurai, Atsushi Hisano, Masahito Saitou, Masahide Kazari, Takahito Murase, Kozo Suzuki
In port injection, it is difficult to control in-cylinder fuel supply of each cycle in a transient state as cold start (in this paper, cold start is defined as several cycles from cranking at low engine temperature). Hence, THC, which is one of regulated emission gases, is likely to increase at cold start. As one of THC emission reduction approaches at cold start, the optimization of fuel injection specifications (including injection position and spray diameter) is expected to reduce THC emission. Setting injection position as downstream position is expected to secure the in-cylinder fuel supply amount at cold start because of small fuel adhesion amount on an intake port wall and a short distance between the injection position and in-cylinder. The position injection contributes to reduction of THC emission due to elimination of misfire.
2016-11-08
Journal Article
2016-32-0071
Koji Ueno, Hiroyuki Horimura, Akiko Iwasa, Yuji Kurasawa, Pascaline Tran, Ye Liu
Abstract We developed a copper catalyst using zero Platinum group metals (hereafter PGMs) to fit motorcycle specific emission gas environment. Though many research reports to develop catalyst without using PGMs that are precious and costly resources are available, no reports had proven Base Metal Catalyst development to meet actual emission regulation equivalent to PGM catalysts. Compared to conventional PGM catalysts, higher temperature is required to keep high catalytic conversion efficiency by utilizing properties of this Base Metal Catalyst. Thus, this Base Metal Catalyst is located in cross coupling position, though it is rare case in motorcycle. This catalyst location could cause negative impacts on engine knocking, engine performance and drivability. This time, to overcome such negative impacts we optimized whole exhaust system, including parts around catalyst.
2016-11-08
Journal Article
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
Abstract On the basis of extensive experimental works about heterogeneous catalysts, we developed various software for the design of automotive catalysts such as Ultra-Accelerated Quantum Chemical Molecular Dynamics (UA-QCMD), which is 10 million times faster than the conventional first principles molecular dynamics, mesoscopic modeling software for supported catalysts (POCO2), and mesoscopic sintering simulator (SINTA) to calculate sintering behavior of both precious metals (e.g., Pt, Pd, Rh) and supports (e.g., Al2O3, ZrO2, CeO2, or CeO2-ZrO2). We integrated the previous programs in a multiscale, multiphysics approach for the design of automotive catalysts. The method was efficient for a variety of important catalytic reactions in the scope of the automotive emission control. We demonstrated the efficiency of our approach by comparing our data with experimental results including both simple laboratory experiments and chassis dynamometer exhaust gas emission control experiments.
2016-11-08
Journal Article
2016-32-0070
Toyofumi Tsuda, Kazuya Miura, Akio Hikasa, Keiji Hosoi, Fumikazu Kimata
Abstract An exhaust gas purifying catalyst must be durable, i.e., it must maintain a sufficient catalytic performance even after thermal degradation. Therefore, large amounts of platinum group metals (PGMs), such as Pt, Pd, and Rh, should be loaded onto the catalyst substrate. Exhaust gas heat deteriorates the catalyst by sintering the PGM particles, which decreases the active surface area. It is important to reduce the PGM load and many researchers have therefore attempted to carry out PGM load reduction while maintaining sufficient durability. We found that Pt ions could form Pt-hydroxide clusters in a hexahydroxyplatinate (IV) (Pt(OH)6·H2O) nitric acid solution. The Pt-hydroxide cluster size could be controlled by varying the Pt and nitric acid concentrations and solution temperature.
2016-11-08
Journal Article
2016-32-0093
Denis Neher, Fino Scholl, Maurice Kettner, Danny Schwarz, Markus Klaissle, Blanca Giménez Olavarria
Abstract Small natural gas cogeneration engines frequently operate with lean mixture and late ignition timing to comply with NOx emission standards. Late combustion phasing is the consequence, leading to significant losses in engine efficiency. When substituting a part of the excess air with exhaust gas, heat capacity increases, thus reducing NOx emissions. Combustion phasing can be advanced, resulting in a thermodynamically more favourable heat release without increasing NOx but improving engine efficiency. 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 motionless initial conditions for several relative air-fuel ratios (λ = 1.3 to 1.7). Starting from the initial value of λ, the amount of CH4 was maintained constant as a part of the excess air was replaced by exhaust gas.
2016-11-08
Journal Article
2016-32-0072
Fino Scholl, Paul Gerisch, Denis Neher, Maurice Kettner, Thorsten Langhorst, Thomas Koch, Markus Klaissle
Abstract 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.
2016-10-25
Technical Paper
2016-36-0240
Guilherme Bastos Machado, José Eduardo Mautone Barros, Sérgio Leal Braga, Carlos Valois Maciel Braga
Abstract Gasoline is a complex mixture, composed of hundreds of different hydrocarbons. Surrogate fuels decrease the complexity of gasoline and are being used to improve the understanding of internal combustion engines (ICEs) fundamental processes. Computational tools are largely used in ICE development and performance optimization using simple fuels, because it is still not possible to completely model a commercial gasoline. The kinetics and interactions among all the chemical constituents are not yet fully understood, and the computational cost is also prohibitive. There is a need to find suitable surrogate fuels, which can reproduce commercial fuels performance and emissions behavior, in order to develop improved models for fuel combustion in practical devices, such as homogeneous charge compression ignition (HCCI) and spark ignition (SI) engines. Representative surrogate fuels can also be used in fuel development processes.
2016-10-25
Technical Paper
2016-36-0160
Alex de Oliveira, Osmano Souza Valente, José Ricardo Sodré
Abstract This study presents the effects of fuel blends containing 5%, 10%, 15% and 20% of anhydrous ethanol in diesel oil with 20% of biodiesel (B20) on performance, emissions and combustion characteristics of a diesel engine. The engine was tested with its original configuration and in the lower brake specific consumption region, at 1800 RPM. The results showed that in-cylinder peak pressure and heat release rate increased with the use of ethanol. The use of ethanol increased ignition delay and decreased exhaust gas temperature. Brake specific fuel consumption increased with ethanol addition, and fuel conversion efficiency was not affected. Increasing ethanol content in the fuel caused decreased carbon dioxide (CO2), carbon monoxide (CO) and total hydrocarbons (THC) emissions.
2016-10-25
Technical Paper
2016-36-0153
Bernardo Luiz Harry Diniz Lemos, Eduardo Abreu Salomão, Matheus Philipe Ribeiro Viana, Rogério Jorge Amorim
Abstract Two-stroke engines are used in several purposes, such as lawn mowers, chainsaws, power generators and for motorcycles in some dirt tracks competitions. In addition, small Wankel engines are used in snowmobiles, motorized paragliders and range extenders. Both types of engines are known for the great power produced per displacement, ideal for the purposes aforementioned, but its bigger emissions due to lubricating oil mixed with fossil fuels, such as gasoline, do not pass legislation's standards, which limits their use. In order to reduce emissions, tests with ethanol and castor oil, eco-friendly fuel and lubricant, respectively, will be presented to adequate these organic compounds to the engine's operation.
2016-10-25
Technical Paper
2016-36-0158
Luiz Carlos Daemme, Renato Penteado, Fátima Zotin, Sérgio M. Corrêa, Marcelo Risso Errera, André Forcetto
Abstract Over the past decade, society’s concern for the state of the environment has increased. Several actions have been taken by governments, non-governmental organizations, public and private environmental and health agencies to limit pollutant emissions. Within this context, the control of vehicle emissions has become increasingly stringent. Emission limits have been substantially reduced, and the role of unregulated emissions is increasing in importance. Ammonia is the third most abundant nitrogen compound in the atmosphere. Ammonia emissions have received special attention due to their contribution to secondary particulate matter production in the forms of ammonium nitrate (NH4NO3) and ammonium sulfate ((NH4)2SO4). The aim of this work was to evaluate the effect of fuel sulfur content on ammonia emissions in a Euro III motorcycle.
2016-10-25
Technical Paper
2016-36-0167
Fábio Coelho Barbosa
Abstract Emissions from motor vehicles have been a subject of concern in urban areas, as great amounts of population have been permanently exposed to large amounts of pollutants, with intrinsic adverse health effects. In this context, in the last two decades, stringent emissions standards have been developed to control the maximum emission limits of the so called regulated pollutants. This continuous reduction of emission targets has imposed a great effort to engine and vehicle manufacturer in the development of technological solutions for emission limits compliance, which can be done by reducing engine-out emissions through improvements in combustion process and fuel management system, as well as by using aftertreatment devices in the exhaust system.
2016-10-25
Technical Paper
2016-36-0177
Fábio Coelho Barbosa
Abstract Public transport has been considered the preferred strategy to reduce congestion and pollution from urban road traffic. For low to medium capacity, bus systems are considered the most affordable and flexible mode. Currently, diesel based systems still dominate transit bus market, due to their high productivity, low deployment costs, technological maturity, operational reliability and flexibility (high daily ranges, fast refuelling and no infrastructure requirement along the routes). However, although some important improvements in engine technology and aftertreatment devices, enforced by emission standards improvements (Euro VI, US 2010 and those related), have been achieved, it is well known that there is a limit to cleaning exhaust diesel buses exhaust. In this context, transit authorities and operators have been under pressure to shift for more environmental friendly technologies.
2016-10-25
Technical Paper
2016-36-0334
Antonio H. Dutra Cardoso, Eduardo Hiroaki Nishi, Rodolfo Silva Guimarães
Abstract Currently the high demand for quality and low pollutant emissions in the Diesel commercial vehicles market, it is notable the increase in the sensitivity variation of components. In a commercial vehicle, we have the engine as the main agent, since it has many components under industrial manufacturing processes which may present variations, mainly when it requires critical adjustments. One of the most significant components in the engine performance is the turbocharger. Based on the difficulty to meet the design specification adjustment, this study was performed to detect the possible influences of the waste-gate actuator adjustment. In addition, the study also considers the contribution in terms of emissions, whereas the current legislation requires stringent levels. Therefore, the research was divided into vehicle tests (performance) in a controlled test track with different settings and emissions tests in a steady-state dynamometer.
2016-10-25
Technical Paper
2016-36-0399
Heder Fernandes, Charles Quirino Pimenta, Wanderson Navegantes Rodrigues, Raphael Bezerra de Souza Montemor, José Eduardo Mautone Barros
Abstract Exhaust Gas Recirculation - EGR - is a well-known technique to reduce NOx and it’s been applied on Diesel engines for a long time. Later studies and application found that other benefits can be achieved with PFI and GDI gasoline engines, such as pumping loss minimization and efficient knock control. Variable valve actuation valve-trains brought broader application possibilities as it enables full internal EGR control without external paths, high precision and response, as required on transient work modes. Comprehensive investigation on PFI and GDI Spark Ignition engines with external Hot EGR and Cooled EGR are widely available. However, variable valve actuation EGR control review on a flexfuel application is not well explored, and this paper is aimed at doing such.
2016-10-25
Technical Paper
2016-36-0387
Fernando Antonio Rodrigues Filho, Alysson Fernandes Teixeira, José Guilherme Coelho Baêta, Márcio Expedito Guzzo, Marcelo Suman Silva Assis
Abstract The emission of nitric oxide (NOx) is the most difficult to limit among numerous harmful exhaust gas components. The NOX emission of internal combustion engines is mainly NO, but it will be oxidized into NO2 quickly after entering the air. NO is formed inside the combustion chamber in post-flame combustion by the oxidation of nitrogen from the air in conditions that are dependent on the chemical composition of the mixture, temperature and pressure. The correlation between NO emissions and temperature in the combustion chamber is a result of the endothermic nature of these reactions and can be described by extended Zeldovich Mechanism. The stratified torch ignition engine is able to run with lean mixture and low cyclic variability. Due to lean operation, the in-cylinder temperature of the STI engine is significantly lower than the conventional spark ignited one. This fact lead to a substantial reduction in NOx specific emission.
2016-10-25
Technical Paper
2016-36-0426
Eduardo Orfale Junior, Andre Luiz, Lessandre Serigiolle, Mauro Marcial
Abstract Currently in the general industry, the awareness of the population and the governments concerns for the environment and processes, such as sustainable products is increasing each year. The automotive industry follows the same trend. In a vehicle, 99% of its components can be recycled. These recyclables can supply the own automotive industry, and other industries as well, such as the manufacture of batteries made with recycled metal vehicles. Recycling vehicles also provides energy saving, conserving natural resources, and reducing water and air pollution, eliminating in a proper way harmful emissions in the environment as the lead and mercury. It is estimated that the market for recycling vehicles in the United States, injects 32 billion dollars every year in the economy, employing more than 140,000 people and have approximately 9,000 local collection and recycling.
2016-10-25
Technical Paper
2016-36-0443
Vinícius Rückert Roso, Mario Eduardo Santos Martins
Abstract Reducing environmental pollution by the transport sector has been influenced according to the increasingly restrictions imposed by regulatory standards. For this, legislation such as Euro (at global level) and Proconve (at local level) set new limits each new phase, usually stipulating reductions in the levels of greenhouse gas emissions. Compliance with these requirements is seen with the vehicle or engine ratings working through the conditions imposed by a standard test cycle. However, standard driving conditions often do not represent the real-world driving conditions, being influenced by relief, traffic lights and other peculiarities of each city or route. This paper aims to compare real-world driving cycles of urban bus and passenger car in the city of Santa Maria, in southern Brazil, with the conditions used for light gasoline vehicles and heavy diesel vehicles approval.
2016-10-25
Technical Paper
2016-36-0477
Fernando Antonio Rodrigues Filho, Alysson Fernandes Teixeira, José Guilherme Coelho Baêta, Márcio Expedito Guzzo, Marcelo Suman Silva Assis
Abstract A global effort has been made by the scientific community to promote significant reduction in vehicle engine out-emission. To comply with this goal a stratified torch ignition (STI) engine is built from a commercial existing baseline engine. In this system, combustion starts in a pre-combustion chamber, where the pressure increase pushes the combustion jet flames through calibrated nozzles to be precisely targeted into the main chamber. These combustion jet flames are endowed with high thermal and kinetic energy, being able to generate a stable lean combustion process. The high kinetic and thermal energy of the combustion jet flame results from the load stratification. The engine out-emissions of CO, HC and CO2 of the STI engine are presented, analyzed and compared with the baseline engine. The STI engine showed a significant decrease in the specific emissions of CO and CO2.
2016-10-25
Technical Paper
2016-36-0538
ROBERTO TETSUO FUJIYAMA, CESAR TADEU NASSER MEDEIROS BRANCO, CARLINDO LINS PEREIRA FILHO, BERNARDO BORGES POMPEU NETO, PAULO SÉRGIO MAGALHÃES FERREIR DE SOUZA, DENILSON DA SILVA COSTA
Abstract Composite materials are alternative materials that come rising fast at last decades. With a view to the use of lighter and stronger materials that can replace ferrous materials, arise composites reinforced by synthetic fibers. Moreover, natural fibers emerge as an alternative reinforcement for the synthetic fibers because they are costly. Thus the present study aims to evaluate the behavior of particulate composite reinforced by sisal fibers in the size of 15 mm emerged in fluids such as water, salt water, and lubricating oil. The specimens were made according to ASTM D638M and aging it period of sixty days. After two months, the specimens were subjected to tensile tests, and determined the tensile strength results and deformation of the maximum load and the modulus of elasticity. In general, it was observed a reduction in tensile strength of the particulate sisal composite when immersed into the lubricant oil.
2016-10-24
Journal Article
2016-01-9075
Martijn van Essen, Sander Gersen, Gerco van Dijk, Torsten Mundt, Howard Levinsky
Abstract The effects of air humidity on the knock characteristics of fuels are investigated in a lean-burn, high-speed medium BMEP engine fueled with a CH4 + 4.7 mole% C3H8 gas mixture. Experiments are carried out with humidity ratios ranging from 4.3 to 11 g H2O/kg dry air. The measured pressure profiles at non-knocking conditions are compared with calculated pressure profiles using a model that predicts the time-dependent in-cylinder conditions (P, T) in the test engine (“combustion phasing”). This model was extended to include the effects of humidity. The results show that the extended model accurately computes the in-cylinder pressure history when varying the water fraction in air. Increasing the water vapor content in air decreases the peak pressure and temperature significantly, which increases the measured Knock Limited Spark Timing (KLST); at 4.3 g H2O/kg dry air the KLST is 19 °CA BTDC while at 11 g H2O/kg dry air the KLST is 21 °CA BTDC for the same fuel.
2016-10-24
Journal Article
2016-01-9078
Herbert Feld, Nadine Oberender
Abstract Biodiesel contains a variety of compounds, depending on the production and the provenance of the fuel. During the production process and usage, some of these compounds can form deposits (nozzle tip deposits or internal diesel injector deposits: “IDID”), which may lead to severe problems, such as corrosion, filter blockage and other technical issues. To deal with these difficulties, it is essential to exactly determine the components of these deposits. Most analytical methods used before, require complex preparations and result in limited information of the deposit material. Using infrared microscopy (ATR-FTIR: Attenuated-Total-Reflection Fourier-Transform-Infrared-Spectroscopy) or mass spectrometry (TOF-SIMS: Time-of-Flight Secondary-Ion-Mass-Spectrometry), a direct analysis of the original deposit material is possible.
2016-10-24
Journal Article
2016-01-9079
Ryoko Sanui, Katsunori Hanamura
Time-lapse images of particulate matter (PM) deposition on diesel particulate filters (DPFs) at the PM-particle scale were obtained via field-emission scanning electron microscopy (FE-SEM). This particle scale time-series visualization showed the detailed processes of PM accumulation inside the DPF. First, PM introduced into a micro-pore of the DPF wall was deposited onto the surface of SiC grains composing the DPF, where it formed dendritic structures. The dendrite structures were locally grown at the contracted flow area between the SiC grains by accumulation of PM, ultimately constructing a bridge and closing the porous channel. To investigate the dominant parameters governing bridge formation, the filtration efficiency by Brownian diffusion and by interception obtained using theoretical filtration efficiency analysis of a spherical collector model were compared with the visualization results.
2016-10-17
Technical Paper
2016-01-2219
Pramit Baul, Courtney Tamaro, Hrusheekesh Warpe, William Baumann, Douglas Nelson
Abstract EcoRouting refers to determining a route that minimizes vehicle energy consumption compared to traditional routing methods, which usually attempt to minimize travel time. EcoRoutes typically increase travel time and in some cases this increase may have to be constrained for the route to be viable. While significant research on EcoRouting exists for conventional vehicles, incorporating the novel aspects of plug-in hybrids opens up new areas to be explored. A prototype EcoRouting system has been developed that takes in map information and converts it to a graph of nodes containing route information such as speed and grade. The route with the minimum energy consumption is selected as the EcoRoute unless there is more than an 8% difference between the minimum time route and the EcoRoute.
2016-10-17
Technical Paper
2016-01-2215
Hubertus Ulmer, Ansgar Heilig, Simon Bensch, Timo Schulteis, Jan-Kirsten Grathwol, Felix Gollmer, Christian Hofrath, Matthias Rühl
Abstract This paper focuses on the hydraulic losses of the low-pressure diesel fuel path and the impact of these losses on the fuel consumption and therefore CO2 emissions of internal combustion engines. In this context, a 1D (one-dimensional) simulation model with implemented fluid flow physics was developed. A 3D CFD model for considering complex geometries of several fuel path components further enhances the 1D approach. Experimental data from a test bench, carrying the complete fuel pressure system, were used for validations and continuous developments of the simulation models. The results show a substantial potential of the low-pressure system regarding a reduction of CO2 emissions, depending on the control strategy of the electric fuel pump and the geometrical properties of the fuel pipes and couplings. Within the New European Driving Cycle, a potential of up to 1.1 g CO2/km was observed.
2016-10-17
Technical Paper
2016-01-2216
Brad Richard, Martha Christenson, Deborah Rosenblatt, Aaron Conde
Abstract Alternative fuels and power trains are expected to play an important role in reducing emissions of greenhouse gases (GHGs) and other pollutants. In this study, five light-duty vans, operating on alternative fuels and propulsion systems, were tested on a chassis dynamometer for emissions and efficiency. The vehicles were powered with Tier 2 gasoline, low blend ethanol (E10), compressed natural gas (CNG), liquefied petroleum gas (LPG), and an electric battery. Four test cycles were used representing city driving and cold-start (FTP-75), aggressive high speed driving (US06), free flow highway driving (HWFCT), and a combination of urban, rural, and motorway driving (WHVC). Tests were performed at a temperature of 22°C, with select tests at -7°C and -18°C. Exhaust emissions were measured and characterized including CO, NOX, THC, PM and CO2. On the FTP-75, WHVC, and US06 cycles additional exhaust emission characterization included N2O, and CH4.
2016-10-17
Technical Paper
2016-01-2231
Aras Mirfendreski, Andreas Schmid, Michael Grill, Michael Bargende
Abstract Longitudinal models are used to evaluate different vehicle-engine concepts with respect to driving behavior and emissions. The engine is generally map-based. An explicit calculation of both fluid dynamics inside the engine air path and cylinder combustion is not considered due to long computing times. Particularly for dynamic certification cycles (WLTC, US06 etc.), dynamic engine effects severely influence the quality of results. Hence, an evaluation of transient engine behavior with map-based engine models is restricted to a certain extent. The coupling of detailed 1D-engine models is an alternative, which rapidly increases the model computation time to approximately 300 times higher than that of real time. In many technical areas, the Fourier transformation (FT) method is applied, which makes it possible to represent superimposed oscillations by their sinusoidal harmonic oscillations of different orders.
2016-10-17
Technical Paper
2016-01-2249
Akash Gangwar, Abhinav Bhardawaj, Ramesh Singh, Naveen Kumar
Abstract 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
2016-01-2283
Stephane Zinola, Stephane Raux, Mickael Leblanc
Abstract The more and more stringent regulations on particle emissions at the vehicle tailpipe have led the car manufacturers to adopt suitable emissions control systems, like particulate filters with average filtration efficiency that can exceed 99%, including particulate mass (PM) and number (PN). However, there are still some specific operating conditions that could exhibit noticeable particle number emissions. This paper aims to identify and characterize these persistent sources of PN emissions, based on tests carried out both at the engine test bench and at the chassis dynamometer, and both for Diesel and Gasoline direct injection engines and vehicles. For Diesel engines, highest particle numbers were observed downstream of the catalyzed DPF during some operation conditions like engine warm up or filter regeneration phases.
2016-10-17
Technical Paper
2016-01-2300
Mengqin Shen, Martin Tuner, Bengt Johansson, Per Tunestal, Joakim Pagels
Abstract In order to reduce nitrogen oxides (NOx) and soot emissions while maintaining high thermal efficiency, more advanced combustion concepts have been developed over the years, such as Homogeneous Charge Compression Ignition (HCCI) and Partially Premixed Combustion (PPC), as possible combustion processes in commercial engines. Compared to HCCI, PPC has advantages of lower unburned hydrocarbon (UHC) and carbon monoxide (CO) emissions; however, due to increased fuel stratifications, soot emissions can be a challenge when adding Exhaust-Gas Recirculation (EGR) gas. The current work presents particle size distribution measurements performed from HCCI-like combustion with very early (120 CAD BTDC) to PPC combustion with late injection timing (11 CAD BTDC) at two intake oxygen rates, 21% and 15% respectively. Particle size distributions were measured using a differential mobility spectrometer DMS500.
2016-10-17
Technical Paper
2016-01-2320
Tsuyoshi Asako, Ryuji Kai, Tetsuo Toyoshima, Claus Vogt, Shogo Hirose, Shiori Nakao
Abstract Ammonia Selective Catalytic Reduction (SCR) is adapted for a variety of applications to control nitrogen oxides (NOx) in diesel engine exhaust. The most commonly used catalyst for SCR in established markets is Cu-Zeolite (CuZ) 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 550°C to avoid vanadium sublimation due to active regeneration of the diesel particulate filter (DPF), or some OEMs may eliminate the DPF because they can achieve particulate matter (PM) standard with 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.
Viewing 271 to 300 of 21875