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Training / Education
2015-04-20
As diesel emissions regulations have become more and more stringent, diesel particulate filters (DPF) have become possibly the most important and complex diesel aftertreatment device. This seminar covers many DPF-related topics using fundamentals from various branches of applied sciences such as porous media, filtration and materials sciences and will provide the student with both a theoretical as well as an applications-oriented approach to enhance the design and reliability of aftertreatment platforms. Structure, geometry, composition, performance, applications and optimizations of DPFs are some of the main topics covered in this advanced level seminar.
Training / Education
2014-11-06
Stringent requirements of reduced NOx emission limits in the US have presented engineers and technical staff with numerous challenges. Several in-cylinder technical solutions have been developed for diesel engines to meet 2010 emission standards. These technologies have been optimized and have yielded impressive engine-out results in their ability to reduce emissions to extremely low levels. However, current and state-of-the-art in-cylinder solutions have fallen short of achieving the limits imposed on diesel emissions for 2010. To help meet emissions requirements, the catalyst industry has developed exhaust emission reduction technologies with impressive levels of performance.
Technical Paper
2014-10-13
Mohammad Reza Hamedi, Athanasios Tsolakis, Jose Martin Herreros
Abstract Recent developments in diesel engines lead to increased fuel efficiency and reduced exhaust gas temperature. Therefore more energy efficient aftertreatment systems are required to comply with tight emission regulations. In this study, a computational fluid dynamics package was used to investigate the thermal behaviour of a diesel aftertreatment system. A parametric study was carried out to identify the most influential pipework material and insulation characteristics in terms of thermal performance. In the case of the aftertreatment pipework and canning material effect, an array of different potential materials was selected and their effects on the emission conversion efficiency of a Diesel Oxidation Catalyst (DOC) were numerically investigated over a driving cycle. Results indicate that although the pipework material's volumetric heat capacity was decreased by a factor of four, the total emission reduction was only considerable during the cold start. Different insulation strategies (e.g. double layer pipe with air gap and vacuum) were simulated using CFD and the improvement in the DOC emission conversion was monitored over the New European Driving Cycle (NEDC).
Technical Paper
2014-10-13
Norifumi Mizushima, Daisuke Kawano, Hajime Ishii, Yutaka Takada, Susumu Sato
Abstract Widespread use of biofuels for automobiles would greatly reduce CO2 emissions and increase resource recycling, contributing to global environmental conservation. In fact, activities for expanding the production and utilization of biofuels are already proceeding throughout the world. For diesel vehicles, generally, fatty acid methyl ester (FAME) made from vegetable oils is used as a biodiesel. In recent years, hydrotreated vegetable oil (HVO) has also become increasingly popular. In addition, biomass to liquid (BTL) fuel, which can be made from any kinds of biomass by gasification and Fischer-Tropsch process, is expected to be commercialized in the future. On the other hand, emission regulations in each country have been tightened year by year. In accordance with this, diesel engines have complied with the regulations with advanced technologies such as common-rail fuel injection system, high pressure turbocharger, EGR and aftertreatment system. Unfortunately, the engine control system with these advanced technologies is adapted to conventional diesel fuels.
Technical Paper
2014-10-13
Rong Ma, Chao He, Jiaqiang Li
A simulation model of catalyzed diesel particulate filter (CDPF) is established based on the CFD software FIRE and has been validated through a series of experimental comparison. This model simulates the CDPF continuous regeneration process, and the factors that influence the exhaust NO2 concentration from CDPF including oxygen concentration, exhaust temperature, space velocity, proportion of NO2/NOX and soot mass fraction are studied. The results show that the higher oxygen concentration causes an increase in NO2/NOX. The NO2/NOX is significantly increased when the exhaust temperature is about 350 °C based on the simulation conditions when the inlet oxygen concentration is at 5.79% and the space velocity is 7s−1. The space velocity in a certain degree leads to higher NO2/NOX. For the soot mass, there is no significant influence of increasing proportion of the NO2/NOX.
Event
2014-10-08
This session discusses technologies that treat engine exhaust emissions to meet commercial vehicle requirements. The scope covers developments in catalysts, materials, controls, and integration with the complete engine/vehicle system.
Event
2014-10-08
This session discusses technologies that treat engine exhaust emissions to meet commercial vehicle requirements. The scope covers developments in catalysts, materials, controls, and integration with the complete engine/vehicle system.
Technical Paper
2014-09-30
Alexander Sappok, Leslie Bromberg
Abstract Diesel Particulate Filters (DPF) are a key component in many on- and off-road aftertreatment systems to meet increasingly stringent particle emissions limits. Efficient thermal management and regeneration control is critical for reliable and cost-effective operation of the combined engine and aftertreatment system. Conventional DPF control systems predominantly rely on a combination of filter pressure drop measurements and predictive models to indirectly estimate the soot loading state of the filter. Over time, the build-up of incombustible ash, primarily derived from metal-containing lubricant additives, accumulates in the filter to levels far exceeding the DPF's soot storage limit. The combined effects of soot and ash build-up dynamically impact the filter's pressure drop response, service life, and fuel consumption, and must be accurately accounted for in order to optimize engine and aftertreatment system performance. This work applied a radio frequency (RF) sensor to directly monitor diesel particulate filter soot and ash levels, thereby enabling direct feedback control of the filter based on its actual loading state.
Technical Paper
2014-09-30
Britney J. McCoy, Arman Tanman
Abstract In-use testing of diesel emission control technologies is an integral component of EPA's verification program. Device manufacturers are required to complete in-use testing once 500 units have been sold. Additionally, EPA conducts test programs on randomly selected retrofit devices from installations completed with grants by the National Clean Diesel Campaign. In this test program, EPA identified and recovered a variety of retrofit devices, including diesel particulate filters (DPFs) and diesel oxidation catalysts (DOCs), installed on heavy-duty diesel vehicles (on-highway and nonroad). All of the devices were tested at Southwest Research Institute in San Antonio, Texas. This study's goal was to evaluate the durability, defined here as emissions performance as a function of time, of retrofit technologies aged in real-world applications. A variety of operating and emissions criteria were measured to characterize the overall performance of the retrofit devices on an engine dynamometer.
Technical Paper
2014-09-30
Harry Dwyer, Seungju Yoon, David Quiros, Mark Burnitzki, Roelof Riemersma, Donald Chernich, John Collins, Jorn Herner
Abstract A novel ambient dilution tunnel has been designed, tested and employed to measure the emissions from active parked regenerations of Diesel Particulate Filters (DPFs) for 2007 and 2010 certified heavy duty diesel trucks (HDDTs). The 2007 certified engine had greater regulated emissions than the 2010 certified engine. For a fully loaded 2007 DPF there was an initial period of very large mass emissions, which was then followed by very large number of small particle emissions. The Particle Size Distribution, PSD, was distributed over a large range from 10 nm to 10 μm. The parked regenerations of the 2010 DPF had a much lower initial emission pattern, but the second phase of large numbers of small particles was very similar to the 2007 DPF. The emission results during regeneration have been compared to total emissions from recent engine dynamometer testing of 2007 and 2010 DPFs, and they are much larger. Due to the very wide spectrum in the PSD a wide variety of instrumentation was used, which included the following: (1) Engine On-board diagnostics; (2) Exhaust flow PEMS; (3) Tunnel temperature, CO2, mixture dilution ratio, and relative humidity; (4) Real-time PM instrumentation: EEPS, SMPS, DustTrak, and Dekati Mass Monitor; and (5) Gravimetric filter media.
Technical Paper
2014-09-30
Meng-Huang Lu, Figen Lacin, Daniel McAninch, Frank Yang
Abstract Diesel exhaust aftertreatment solutions using injection, such as urea-based SCR and lean NOx trap systems, effectively reduce the emission NOx level in various light vehicles, commercial vehicles, and industrial applications. The performance of the injector plays an important role in successfully utilizing this type of technology, and the CFD tool provides not only a time and cost-saving, but also a reliable solution for extensively design iterations for optimizing the injector internal nozzle flow design. Inspired by this fact, a virtual test methodology on injector dosing rate utilizing CFD was proposed for the design process of injector internal nozzle flows. For a low-pressure (less than 6 bar) injector application, the characteristic Reynolds number based on the diameter and mass flow rate of the inlet, return flow outlet, and nozzle exit of the injector might range from 2000 to 20000, therefore, employing a flow-physics based viscous model for building up a virtual test methodology is critical to properly capture the fluid dynamics of injector internal nozzle flow.
Technical Paper
2014-09-30
Xinyu Ge, Yongli Qi, Kai Zhang
Fuel properties impact the engine-out emission directly. For some geographic regions where diesel engines can meet emission regulations without aftertreatment, the change of fuel properties will lead to final tailpipe emission variation. Aftertreatment systems such as Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) are required for diesel engines to meet stringent regulations. These regulations include off-road Tier 4 Final emission regulations in the USA or the corresponding Stage IV emission regulations in Europe. As an engine with an aftertreatment system, the change of fuel properties will also affect the system conversion efficiency and regeneration cycle. Previous research works focus on prediction of engine-out emission, and many are based on chemical reactions. Due to the complex mixing, pyrolysis and reaction process in heterogeneous combustion, it is not cost-effective to find a general model to predict emission shifting due to fuel variation. Some empirical models use testing data as input to locate relationships between controlled inputs and engine response.
Technical Paper
2014-09-30
Xiangang Wang, Zhangsong ZHAN, Tiegang Hu, Zuohua Huang
Abstract Experiments were conducted in a turbocharged, high-pressure common rail diesel engine to investigate particulate emissions from the engine fueled with biodiesel and diesel blends. An electrical low-pressure impactor (ELPI) was employed to measure the particle size distribution and number concentration. Heated dilution was used to suppress nuclei mode particles and focus on accumulation mode particles. The experiment was carried out at five engine loads and two engine speeds. Biodiesel fractions of 10%, 20%, 40%, 60% and 80% in volume were tested. The study shows that most of the particles are distributed with their diameters between 0.02 and 0.2 μm, and the number concentration becomes quite small for the particles with the diameters larger than 0.2 μm. With the increase of biodiesel fraction, engine speed and/or engine load, particle number concentration decreases significantly, while the particle size distribution varies little. The analysis on heat release rate, excess air ratio and exhaust gas temperature were provided to help interpret the particulate emissions.
Event
2014-09-18
Evolution of diesel aftertreatment systems needs to target complex challenges such as CO2 / GHG reduction, in-use compliance, OBD, reduction of development, installation and operation costs, and integration of emerging technologies. Modeling and simulation tools help meeting these challenges through in-depth understanding of component performance and interactions, faster calibration process, improved robustness, and overall system optimization. The presentation discusses the model-based development process, beginning with modeling the system components, followed by integration with control algorithms into a system model, and then into a powertrain or vehicle model. Issues such as in-service conformity, NTE, and system robustness are addressed.
Event
2014-09-18
This presentation will cover recent developments in technology to reduce heavy duty engine CO2 emissions, focussing on measures to reduce engine friction, investigations with a high pressure common rail system, and the application of a highly efficient SCR system.
Event
2014-09-18
Event
2014-09-18
Global harmonization of emission limits and regulations is the basis for introducing efficient emission control technologies on a global scale with minor regional adaptations. Proportionality between emissions reductions on the test bench and under real world operating conditions, which is a key requirement for air quality control, is being checked with portable emissions measurement systems (PEMS). An emissions test procedure for heavy duty hybrids was recently adopted by GRPE. Since emissions from Euro VI and Stage IV/V engines are already close to zero, further emissions reductions will not significantly improve air quality. Regulations should rather focus on CO2 reductions taking the whole vehicle or machine into account.
Event
2014-09-18
If the production of harmful emissions is prevented already during combustion then the expensive and space consuming Emissions After-Treatment System (EATS) can be removed. The reduction of CO2 emissions can anyway not be achieved with EATS, but requires increased engine efficiency or a fuel with reduced amount of “fossil” carbon. The research into Homogeneous Charge Compression Ignition (HCCI) created a completely new foundation for perspectives on clean and efficient engine combustion – fast combustion that improves thermodynamic efficiency - lean premixing for low temperature combustion that reduces emissions of NOx and soot. However, where HCCI is more of an idealized process, Partially Premixed Combustion (PPC) carries the legacy further into practical engines with increased controllability, very high load capability and efficiency as well as unrivaled fuel flexibility. The presentation discusses the evolution from DI-Diesel through HCCI to PPC. Insights to the coming PPC production engines are given as well as an outlook of how PPC paves the way for new well-to-wheel efficient and clean fuels.
Event
2014-09-18
In 2008, Scania started to develop an exhaust aftertreatment system for Euro 6. For Euro 5, Scania had taken the decision to go for heavy EGR with a two-stage EGR cooling solution enabling Euro 5 without SCR. But for Euro 6, it was obvious that EGR alone would not be a successful technical strategy. In 2011, Scania, as the first OEM in the heavy truck industry, launched a ready-to-order truck fulfilling Euro 6 emission standards, featuring a combined EGR and SCR solution. Today, Scania deliver Euro6 trucks with SCR-only and believe that is the path to go in the future. In the presentation, Scania Euro6 development is described along with the strategy behind it and the first two years of field experience is shared.
Event
2014-09-18
Event
2014-09-18
With Euro VI being in place, drivers for further development of exhaust aftertreatment systems will be primarily fuel efficiency, cost reduction and durability improvements. Performance enhancements of individual components are possible and ongoing. In order to cope with reduced exhaust temperatures new system approaches are favourable. Among these, SCR on filter concept is the most advanced. Open questions and challenges will be discussed and analyzed. This includes filtration efficiency, filter regeneration, NO2 performance as well as ash and soot effects. Also, the standard muffler layout has to be questioned.
Event
2014-09-18
The presentation summarises the development status for this Cordierite and SiC Filters for on-road and off-road heavy duty applications. An outlook will be given on potential filter material options for future post EU VI and Tier V applications. Special focus is on particulate number emission results and pressure drop. For CSF, thin wall filter materials in various test cycles are investigated for filter design. Especially SCR catalysts on DPF require a good selection of the filter material to achieve both a sufficient coating and particulate number test results in on-road and off-road test cycles. The DPF material selection depends also pressure drop performance. To get best compromise between NOx performance and backpressure the coating and material has to be optimised and the mean pore size of the DPF adjusted. Further development work on material and coating optimisation is needed and still on going.
Event
2014-09-18
Emission control legislation in the developed markets of Europe, North America and Japan has resulted in the reduction of millions of tonnes of potential emissions from Heavy Duty Diesel (HDD) vehicles, leading to major environmental benefits. In order to meet the regulations, sophisticated catalyst-based systems have been developed which typically reduce emissions of CO, HC, NOx and Particulate Matter (PM) by over 90%. These systems typically comprise a Diesel Oxidation Catalyst (DOC), Catalysed Soot Filter (CSF), Selective Catalytic Reduction (SCR) catalysts, and an Ammonia Slip Catalyst (ASC). Despite the very high efficiencies of these systems, which are maintained for half a million miles and more, there is continued drive for further improvements to enable, for example, additional increases in fuel efficiency, which is a key driver in the HDD area, particularly in the on road sector. There are also proposals from California’s ARB for an optional, much tighter, NOx standard on the 2020 timeframe.
Event
2014-09-18
To meet Euro VI emissions requirements has been the central development focus for the current generation of HD diesel engines in the past. Today – after having achieved this challenging target reliable – the development focus changes. Facing significantly increased product cost as well as upcoming legal fuel efficiency respectively CO2 emissions targets, now improved fuel efficiency as well as the reduction of product cost are the main development targets of next generation HD diesel engines. In this presentation AVL will highlight the potentials and challenges of advanced technologies for next generation HD diesel engines, like high advanced air handling, consequent engine downspeeding, advanced aftertreatment systems, waste heat recovery, etc...
Event
2014-09-18
Someday, the story of a well-proven engine concept inevitably comes to an end. In the mid-nineties, the 900 series replaced the legendary engines of the 300 class, which formed the backbone of the Mercedes-Benz medium duty powertrain since 1949. Fifteen years later, Daimler Trucks is now presenting the engines OM 934 and OM 936 of the new developed Medium Duty Engine Generation (MDEG) to replace this likewise successful 900 engine class. The presentation illustrates selected highlights of the MDEG’s thermodynamic concept as well as the technology of catalysis and exhaust gas filtration in consideration of the constraints of the EURO VI and the EU-Stage IV/Tier 4 final legislation.
Event
2014-09-17
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