Criteria

Text:
Display:

Results

Viewing 1 to 30 of 2263
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.
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.
Training / Education
2014-10-01
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.
Technical Paper
2014-09-30
Zhiguo Zhao, Guanyu Zheng, Fengshuang Wang, Suying Zhang, Jianhua Zhang
In order to satisfy China IV emissions regulations, an unique design was proposed with injector closely coupled with SCR outer body. The benefit of this design is that the system mixing pipe can be shortened, resulting in smaller packaging space and lower cost of decomposition pipe. However, the shorter urea mixing distance generates concerns on lower urea mixing efficiency and higher risks of urea deposits. Aftertreatment systems need to be properly engineered to resolve these technical challenges. Systematic enhancements of the design have been performed to enable multiple designs to meet a set of performance targets, including emission reduction efficiency via improved reagent mixing, evaporation, distribution, back pressure, and removing of urea deposits. The optimized system improved NOx reduction uniformity, eliminated urea deposits, improved NOx conversion efficiency while satisfy existing installation packing space. This study demonstrates that good system performance can be achieved despite the challenges of meeting strict and often-conflicting performance targets.
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.
Technical Paper
2014-09-30
Britney J. McCoy, Arman Tanman
In-use testing of verified 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 used within the National Clean Diesel Campaign grant programs. In this test program, EPA identified and recovered a variety of retrofit devices installed on heavy-duty diesel vehicles (on-highway and off-road) including diesel particulate filters (DPFs) and diesel oxidation catalysts (DOCs). All of the devices were tested at Southwest Research Institute. The goal was to evaluate the emissions performance and durability of retrofit technologies aged in real-world applications. In assessing the emissions reducing performance of these after-treatment technologies, a variety of different test methods were used to characterize the overall performance of the retrofit devices on an engine dynamometer.
Technical Paper
2014-09-30
Manoj K. Sampath, Figen Lacin
Diesel engine combustion process results in harmful exhaust emissions mainly composed of Particulate Matter (PM), Hydro Carbon (HC), Carbon monoxide (CO) and Nitrogen Oxides (NOx). Several technologies utilizing catalyst has been developed in the past decades to control these diesel emissions. Reduction of PM by advanced combustion research often results in increase of NOx due to more complete combustion and hence reducing NOx becomes even more challenging. One of the promising and well matured technology of reducing NOx is to implement Selective Catalytic Reduction (SCR) using ammonia (NH3) as the reducing agent. The generation of NH3, in this case, is from the evaporation of Diesel Exhaust Fluid (DEF) or liquid urea through thermolysis and hydrolysis process. For an effective SCR system, the mal-distribution of ammonia across the SCR Inlet has to be evenly distributed. There are several commercial Computational Fluid Dynamics (CFD) tools available to predict the SCR flow distribution including ammonia formation from the urea decomposition.
Technical Paper
2014-09-30
Guanyu Zheng, Fengshuang Wang, Sheng Wang, Wei Gao, Zhiguo Zhao, Jian Liu, Lin Wang, Lin Wu, Hongyu Wang
Urea-based SCR has been the mainstream technology to reduce NOx emissions for on-road vehicles and off-road vehicles. In category II marine applications, urea SCR is being considered as an enabling technology to reduce NOx. A typical urea SCR system includes a urea injector, injector housing, mixer, and appropriate pipe configurations. In applications of the SCR technology, urea mixing and deposit mitigation have become severe challenges. Urea deposit issues were encountered in SCR systems designed for large marine engines. To resolve urea deposits, CFD method and tests were applied to investigate urea spray transport, evaporation and droplet-wall phenomena. In system design, multiple design factors are reviewed: (1) overall geometrical layouts; (2) substrate and catalyst selections; (3) urea injector and nozzle selections; (4) miscellaneous issues such as ash cleaning, fuel switching, and etc.
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
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.
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
Event
2014-09-17
To meet its air quality commitments and climate goals, California must reduce NOx and greenhouse gas emissions from today’s levels by an additional 90 percent between 2032 and 2050. Through a mix of regulations and financial incentives, California is implementing comprehensive strategies that include: consideration of new heavy-duty engine standards; in-use regulations that will both accelerate replacement of older vehicles and equipment, as well as better ensure their emission performance; and deployment of advanced technologies. At its core, meeting California’s emission reduction targets will require widespread use of zero and near-zero emission technologies and low-carbon fuels.
Viewing 1 to 30 of 2263

Filter

  • Range:
    to:
  • Year: