Browse Topic: Emissions certification

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This SAE Recommended Practice supersedes SAE J1930 MAR2017 and is technically equivalent to ISO 15031-2. This document is applicable to all light-duty gasoline and diesel passenger vehicles and trucks, and to heavy-duty gasoline vehicles. Specific applications of this document include diagnostic, service and repair manuals, bulletins and updates, training manuals, repair databases, underhood emission labels, and emission certification applications. This document should be used in conjunction with SAE J1930DA Digital Annexes, which contain all of the information previously contained within the SAE J1930 tables. These documents focus on diagnostic terms applicable to electrical/electronic systems, and therefore also contain related mechanical terms, definitions, abbreviations, and acronyms. Even though the use and appropriate updating of these documents is strongly encouraged, nothing in these documents should be construed as prohibiting the introduction of a term, abbreviation, or
Vehicle E E System Diagnostic Standards Committee
In 2023, the European Union set more ambitious targets for reducing greenhouse gas emissions from passenger cars: the new fleet-wide average targets became 93.6 g/km for 2025, 49.5 g/km in 2030, going to 0 in 2035. One year away from the 2025 target, this study evaluates what contribution to CO2 reduction was achieved from new conventional vehicles and how to interpret forecasts for future efficiency gains. The European Commission’s vehicle efficiency cost-curves suggest that optimal technology adoption can guarantee up to 50% CO2 reduction by 2025 for conventional vehicles. Official registration data between 2013 and 2022, however, reveal only an average 14% increase in fuel efficiency in standard combustion vehicles, although reaching almost 23% for standard hybrids. The smallest gap between certified emissions and best-case scenarios is of 14 g/km, suggesting that some manufacturers’ declared values are approaching the optimum. Yet, the majority of vehicles do not appear to fully
Komnos, DimitriosNur, JamilTansini, AlessandroKtistakis, Markos AlexandrosSuarez, JaimeKrause, JetteFontaras, Georgios
Since the emission gap of nitrogen oxides between the measurements in the indoor emission certification test and the driving in real road conditions has revealed to be significant, the RDE(Real Driving Emissions) regulations of exhaust emissions in real road driving in Europe were adopted in 2017 at the Euro 6d-TEMP stage and gradually strengthened thereafter. Many countries including Korea are applying equivalent and similar regulations. In order to identify whether vehicles in use comply with the emission standards within the exhaust emissions warranty period, it is necessary to add real road tests to ongoing in-use inspections. Thus, a study on the development of an indoor test cycle in order to use for in-use inspection instead of an real road test becomes required while satisfying RDE criteria. This study shows that the RDE test conducted in real road driving can be simulated in an indoor chassis dynamometer, and confirms that the RDE regulations including dynamic characteristics
Park, JeonghyunChoi, ByeongheeChoi, SungwoonKim, BadaLee, Chul-heeLee, DaeyupKwon, SangilChung, TaekhoLee, Jongtae
Real driving emission (RDE) tests are influenced by factors such as data processing methods, driving behaviors, and environmental conditions. Therefore, being able to effectively identify test influence factors is particularly important for RDE emissions-based calibrations. In order to investigate the correlation between data processing methods, driving behaviors and vehicle emissions, the moving average window (MAW) method and cumulative averaging (CA) method were used to compare and analyze the RDE tests data of a light-duty gasoline vehicle under different driving modes in this study. The results showed that in MAW method, carbon monoxide (CO) emissions of urban and total trips calculated by using the front to back window division order were slightly lower compared to the back to front window division order, with an average reduction of 4.68% and 6.33%, respectively. For carbon dioxide (CO2) emissions, the order of window division had the opposite effect as for CO emissions. For
Huang, RongNi, JiminShi, XiuyongWang, QiweiCheng, ZhenxuQuan, YifengHuang, Jinquan
This document specifies the procedure to be used for a manufacturer to certify the net power and torque rating of a production engine according to SAE J1349 (Rev. 8/04) or the gross engine power of a production engine according to SAE J1995. Manufacturers who advertise their engine power and torque ratings as certified to SAE J1349 or SAE J1995 shall follow this procedure. Certification of engine power and torque to SAE J1349 or SAE J1995 is voluntary; however, this power certification process is mandatory for those advertising power ratings as “Certified to SAE J1349” or “Certified to SAE J1995.” In the event that an engine made by one manufacturer is sold to a consumer in a vehicle produced by a second manufacturer, engine certification may be completed by either manufacturer or by both manufacturers working together. An example of the latter would be the completion of witness testing by the engine manufacturer with the submission of certification documents by the vehicle
Engine Power Test Code Committee
The battery of a vehicle with an electrified powertrain (Hybrid Electric Vehicle or Battery Electric Vehicle), is required to operate with highly dynamic power outputs, both for charging and discharging operation. Consequently, the battery current varies within an extensive range during operation and the battery temperature also changes. In some cases, the relationship between the current flow and the change in the electrical energy stored seems to be affected by inefficiencies, in literature described as current losses, and nonlinearities, typically associated with the complex chemical and physical processes taking place in the battery. When calculating the vehicle electrical energy consumption over a trip, the change in the electrical energy stored at vehicle-level has to be taken into account. This quantity, what we could call the vehicle electricity balance, is typically obtained through a time-based integration of the battery current of all the vehicle batteries during operation
Tansini, AlessandroFontaras, GeorgiosMillo, Federico
The automotive industry is gearing up to meet the accelerated emission compliance changes posed by the government. This transition to eco-friendly system would also necessitate an automotive engineer to retain the engine packaging as compact and simple as possible. The packaging layout considered should not be at the expense of deteriorating engine performance. The work started with concept level layout development, with the aim of having simplified system with minimum number of components. The engine on which the work was carried out was 4cylinder 3Liter with OHC configuration A number of layouts were developed which included gear type, belt drive and integrated shaft arrangement for driving FIP. Each of these concepts were brainstormed with its advantages and disadvantages, based on which two concepts were initially proposed for driving FIP system (i) Front Driven FIP (ii) Rear Driven FIP. The difference between the two layouts was that in the latter case the FIP system was directly
Kaundabalaraman, KaarthicRathi, HemantkumarBisht, Jasvir Singh
The forecast scenarios regarding the environmental pollution raises a question whether the current vehicle emission certification is reliable enough to assure fleet agreement with the legal limits. Type approval tests have been performed on chassis dynamometer in order to evaluate the emission factors and fuel consumption for passenger cars. Standardized procedures such as the FTP-75 proposed in the United States (currently incorporated in the Brazilian legislation) and the Worldwide harmonized Light vehicles Test Cycle (WLTC), a transient driving cycle model designed by the European Union to overcome the shortcomings of the New European Driving Cycle (NEDC), are discussed in this paper. Both cycles were performed in a chassis dynamometer with a flex-fuel passenger car running on ethanol blend (E92W08). The driver, vehicle and fuel were kept constant so the comparison between the cycles would not be compromised. The vehicle chosen was a 1.4 dm3 displaced volume FIAT sedan with maximum
Mazer, Maria F. P.Hatschbach, Leonardo S.dos Santos, Igor R.Silveira, Juliano P.Garlet, Roberto A.Martins, Mario E. S.Nora, Macklini Dalla
Fuel consumption rate (fuel economy) and exhaust gas emission regulations are being tightened around the world year by year. In Europe, the real driving emission (RDE) method for evaluating exhaust gas emitted from road-going vehicles was introduced after September 2017 for new types of light/medium-duty vehicles, in addition to the chassis dynamometer test using the worldwide harmonized light vehicles test procedure (WLTP). Further, the worldwide harmonized heavy-duty certification (WHDC) method was introduced after 2016 as an exhaust gas emission test method for heavy-duty vehicles. In each evaluation, the tests of vehicles and engines are initiated from cold states. Heavy-duty hybrid vehicles are evaluated using the vehicle simulation method. For example, the power characteristics of a engine model is obtained during engine warm operation. Therefore, various performances during cold start cannot be precisely evaluated by using simulator. In this study, we simultaneously control a
Okui, NobunoriKobayashi, Masayuki
Partially premixed combustion (PPC) has shown to produce high gross indicated efficiencies while yielding lower pollutant emissions, such as oxides of nitrogen and soot, than conventional diesel combustion. Gasoline fuels with a research octane number (RON) of 60-70 have been proposed as optimal for PPC as they balance the trade-off between ensuring good combustion stability at low engine loads and avoiding excessive peak pressure rise rates at high loads. However, measures have to be taken when optimizing the engine operating parameters to avoid soot emissions. In contrast, methanol has a much lower propensity for soot formation. However, due to a higher RON of methanol the required intake temperature is higher for the same engine compression ratio to ensure auto-ignition at an appropriate timing. Increasing the compression ratio allows a lower intake temperature and improves combustion stability as well as engine brake efficiency. Nevertheless, a higher compression ratio generally
Svensson, ErikVerhelst, Sebastian
Climate change is primary driver in the current discussions on CO2 reduction in the automotive industry. Current Type approval emissions tests (BS III, BS IV) covers only tailpipe emissions, however the emissions produced in upstream and downstream processes (e.g. raw material sourcing, manufacturing, transportation, vehicle usage, recycle phases) are not considered in the evaluation. The objective of this project is to assess the environmental impact of the product considering all stages of the life cycle, understand the real opportunities to reduce environmental impact across the product life cycle. As a part of environmental sustainability journey in business value chain, lifecycle assessment (LCA) technique helps to understand the environmental impact categories. To measure overall impact, a cradle to grave approach helps to assess entire life cycle impact throughout various stages. LCA is a technique to assess environmental impacts associated with all the stages of a product's
Lalwani, RahulN, SaravananVeeraputhiran, ArunmozhiD, IlavarasIi
This article focuses on a comparative research of the emissions discharged from four vehicles equipped with SI engines, which comply with different emission control systems (Euro 6, Euro 5, and Euro 3). The vehicles used for this work were installed with two different fuel injection technologies (direct injection and port fuel injection) and were operated with three different types of fuels (RON 95, M15, and E10). The tests were performed at the Joint Research Center (JRC) in Ispra using a state-of-the-art emissions test facility according to the European emissions legislation. The test bench included a chassis dynamometer and two different driving cycles were used: NEDC and US06. The main conclusions observed by this article are: (1) Emissions levels from vehicles fueled with M15 are similar to or lower than from those fueled with RON95. (2) Using M15 has the potential to decrease carbon dioxide emissions and to save fuel on an energetic basis. (3) PM emissions are lower for gasoline
Goldwine, GideonSher, EranSher, Diana
In order to meet the worldwide increasingly stringent particulate matter (PM) and particulate number (PN) emission limits, the diesel particulate filter (DPF) is widely used today and has been considered to be an indispensable feature of modern diesel engines. To estimate the soot loading amount in the DPF accurately and in real-time is a key function of realizing systematic and efficient applications of diesel engines, as starting the thermal regeneration of DPF too early or too late will lead to either fuel economy penalty or system reliability issues. In this work, an open-loop and on-line approach to estimating the DPF soot loading on the basis of soot mass balance is developed and experimentally investigated, through establishing and combining prediction models of the NOx and soot emissions out of the engine and a model of the catalytic soot oxidation characteristics of passive regeneration in the DPF. The emission testing results under the New European Driving Cycle (NEDC) show
Huang, TiexiongHu, GuangdiGuo, FengZhu, Yuanxian
This document provides design guidelines, test procedure references, and performance requirements for omnidirectional and selective coverage optical warning devices used on authorized emergency, maintenance, and service vehicles. It is intended to apply to, but is not limited to, surface land vehicles
Emergency Warning Lights and Devices Standards Committee
Regulations regarding evaporative emissions have set more and more stringent limits over the last years. To fulfill these specifications, original equipment manufacturers (OEMs) now tend to break down the sum value of evaporative emissions for the whole car onto single parts or components. Especially small, fuel-containing components (fuel lines, pressure sensors, injection systems, etc.) are challenging. Very low emission rates (<1 mg/24 h) must be measured precisely, and also the stability of these values must be verified due to fuel equilibration effects. Standard SHED (sealed housing evaporative determination) systems or test chambers for measuring volatile organic compound (VOC) emissions are often too big and have too high background levels to achieve reliable results. In addition they are quite expensive which affects the costs per measurement. Our aim was to develop a low-cost Micro-SHED system which fulfills the abovementioned requirements. Commercial gas-tight aluminum boxes
Brunnermeier, Matthias
The current procedure for testing emissions from new vehicles, the World Harmonised Light Vehicle Test Procedure (WLTP), was introduced in September 2017. The WLTP was developed by collecting over 765,000 kilometres worth of data in order to isolate driver behaviour from other real world variables. However, this is a very time consuming and costly process. This paper discusses the suitability of a cheaper and more time efficient alternative. Driver behaviour has a significant impact on the emissions produced from the same vehicle. This study explores the feasibility of utilising virtual environments as an alternative to real world testing to isolate driver behaviour to develop future drive cycles. The use of virtual environments have some significant advantages over real world testing: they can be strictly controlled in terms of the weather, topography and vehicle characteristics, thereby aiding the isolation of driver behaviour from other variables. A driving simulator facility based
Kay, Peter
Catalyzed gasoline particulate filter (cGPF) is the prime technology to meet future stringent regulations for particulates from gasoline direct injection (GDI) engines. One of the technical concerns is the ultimate durability of cGPF in regards to engine lubricant formulations. This study investigated two tailored lubricant formulations on catalyzed GPFs which were aged on engine followed by emission testing on vehicle. An engine accelerated aging protocol was developed for cGPFs to simulate thermal aging, ash and soot loading that is at least equivalent to 200,000 km durability requirement. Evaluations include tailpipe emission levels, backpressure, catalytic performance, and post-mortem analysis. Both formulations have demonstrated a high level of cGPF performance retention; performance being assessed in terms of emission level at the end of durability demonstration testing. These formulations provide flexibility in selecting robust lubricant to meet various system requirements
Shao, HuifangCarpentier, GuillaumeYin, DanhuaWang, YinhuiRemias, JoesphRoos, JosephXia, WenzhengZheng, YiYuan, XinboYang, DongxiaHe, XiaokunYin, Zenghui
A significant share of the emissions of a vehicle with internal combustion engine originates from the cold start. In addition to the more stringent limits for particulate emissions due the introduction of the Euro 6c standard for gasoline engines with direct injection (GDI), exhaust gas emission testing is currently performed applying the real driving emission test procedure (RDE) required by the Euro 6d TEMP standard. The RDE test procedure is not clearly defined, potentially allowing high loads immediately after the engine start. Under such circumstances the combustion chamber features low surface temperatures impairing emission performance and in particular provoking the excessive generation of hydrocarbon and particulate emissions. It is therefore important not only to examine the heating of the catalytic converter during the cold start, but also the preconditioning of the combustion chamber itself. This paper describes the influence of different catalytic converter heating
Titus, FabianBerlet, PeterSobek, FlorianWessling, Justus
The new European Commission Regulations for vehicle certification include a new laboratory procedure for fuel consumption and require Real Driving Emissions (RDE) to be gauged on-road with Portable Emissions Measurement Systems (PEMS). The goal of this investigation is to underline some critical issues in the development of RDE cycles with particular reference to the repeatability on-road and the reproducibility on-track. More specifically, the study includes an optimization of the route for RDE cycles to ensure robustness with respect to traffic conditions, an analysis of emissions variability on-road in hot weather and a discussion about the possibility to reproduce RDE cycles on-track. The tests were performed with a start&stop Diesel Class3b vehicle that was equipped with a PEMS instrumentation and tested over an optimized route in summer in the southern Italy. The tests on the track were performed on the testing facilities of the Nardò Technical Center. The emissions levels
Donateo, TeresaGiovinazzi, Mattia
To check the regulated emission limits, mass emissions test for a vehicle is conducted on a chassis dynamometer following a driving cycle. However, the driving cycle and laboratory test are different from the real-world driving. This article presents a study conducted on a mid-size gasoline car on chassis dynamometer as well as on-road (real-world). It determines the effect of real-world driving, different drive modes (idle, acceleration, deceleration and cruising) on vehicle emissions and fuel consumption and their comparison with the laboratory data. The emissions tests were conducted on the chassis dynamometer following the Modified Indian Driving Cycle and on the selected traffic routes in Dehradun city using a Portable Emission Measurement System (OBS-2200). It was observed from the study that average on-road emission rates in gram per second were 1.35 to 2.39 times higher for CO, 1.12 to 1.39 times higher for CO2, 2.04 to 2.32 times higher for NOx and 2.17 to 5.0 times higher for
Lairenlakpam, RobindroJain, A.K.Gupta, PoonamKamei, WittisonBadola, RajendraSingh, Yograj
During the course of emissions and fuel economy (FE) testing, vehicles that are calibrated to meet Tier 3 emissions requirements currently must demonstrate compliance on Tier 3 E10 fuel while maintaining emissions capability with Tier 2 E0 fuel used for FE label determination. Tier 3 emissions regulations prescribe lower sulfur E10 gasoline blends for the U.S. market. Tier 3 emissions test fuels specified by EPA are required to contain 9.54 volume % ethanol and 8-11 ppm sulfur content. EPA Tier 2 E0 test fuel has no ethanol and has nominal 30 ppm sulfur content. Under Tier 3 rules, Tier 2 E0 test fuel is still used to determine FE. Tier 3 calibrations can have difficulty meeting low Tier 3 emissions targets while testing with Tier 2 E0 fuel. Research has revealed that the primary cause of the high emissions is deactivation of the aftertreatment system due to sulfur accumulation on the catalysts. The emissions drive cycles used in the test sequence play a significant role in catalyst
White, Eugene D.Anderson, BruceRanspach, Paul
Drive cycles have been an integral part of emission tests and virtual simulations for decades. A drive cycle is a representation of running behavior of a typical vehicle, involving the drive pattern, road characteristics and traffic characteristics. Drive cycles are typically used to assess vehicle performance parameters, perform system sizing and perform accelerated testing on a test bed or a virtual test environment, hence reducing the expenses on road tests. This study is an attempt to design a relatively robust process to generate a real world drive cycle. It is based on a Six Sigma design approach which utilizes data acquired from real world road trials. It explicitly describes the process of generating a drive cycle which closely represents the real world road drive scenario. The study also focuses on validation of the process by simulation and statistical analysis
Kondaru, Murali KrishnaTelikepalli, Kumar PrasadThimmalapura, Satish VPandey, Nabal Kishore
Future LEV-III tailpipe (TP) emission regulations pose an enormous challenge forcing the fleet average of light-duty vehicles produced in the 2025 model year to perform at the super ultralow emission vehicle (SULEV-30) certification levels (versus less than 20% produced today). To achieve SULEV-30, regulated TP emissions of non-methane organic gas (NMOG) hydrocarbons (HCs) and oxygenates plus oxides of nitrogen (NOx) must be below a combined 30 mg/mi (18.6 mg/km) standard as measured on the federal emissions certification cycle (FTP-75). However, when flex-fuel vehicles use E85 fuel instead of gasoline, NMOG emissions at cold start are nearly doubled, before the catalytic converter is active. Passive HC traps (HCTs) are a potential solution to reduce TP NMOG emissions. The conventional HCT design was modified by changing the zeolite chemistry so as to improve HC retention coupled with more efficient combustion during the desorption phase. Increased trapping efficiently was achieved by
Lupescu, JasonXu, LifengNunan, JohnAlltizer, Chad
Light-duty vehicle emission measurement test protocols defined in the Code of Federal Regulation (40 CFR Part 1066) allow sampling particulate matter (PM) of all phases of Federal Test Procedure (FTP-75) on a single PM sampling filter by means of flow-weighted sampling in order to increase PM mass loaded on the filter. A technical challenge is imposed especially for partial flow dilution systems (PFDS) to maintain a precise dilution ratio (DR) over such a wide sample flow range due to the subtraction flow determination method of dilution air and diluted exhaust flows, because the flow difference is critical at high DR conditions. In this study, an improved flow weighting concept is applied to a PFDS by installing a bypass line with a flow controller in parallel with the PM sampling filter in order to improve DR accuracy during flow-weighted sampling. The diluted exhaust flow of the PFDS is kept constant and the flow through the PM sampling filter is adjusted by dividing the total
Otsuki, YoshinoriHaruta, KazuhikoRahman, Montajir
In the development of HC traps (HCT) for reducing vehicle cold start hydrocarbon (HC)/nitrogen oxide (NOx) emissions, zeolite-based adsorbent materials were studied as key components for the capture and release of the main gasoline-type HC/NOx species in the vehicle exhaust gas. Typical zeolite materials capture and release certain HC and NOx species at low temperatures (<200°C), which is lower than the light-off temperature of a typical three-way catalyst (TWC) (≥250°C). Therefore, a zeolite alone is not effective in enhancing cold start HC/NOx emission control. We have found that a small amount of Pd (<0.5 wt%) dispersed in the zeolite (i.e., BEA) can significantly increase the conversion efficiency of certain HC/NOx species by increasing their release temperature. Pd was also found to modify the adsorption process from pure physisorption to chemisorption and may have played a role in the transformation of the adsorbed HCs to higher molecular weight species. Both these processes led
Xu, LifengLupescu, JasonUra, JustinHarwell, AmyPaxton, William A.Nunan, JohnAlltizer, Chad
Effective control of exhaust emissions from modern diesel engines requires the use of aftertreatment systems. Elevated aftertreatment component temperatures are required for engine-out emissions reductions to acceptable tailpipe limits. Maintaining elevated aftertreatment components temperatures is particularly problematic during prolonged low speed, low load operation of the engine (i.e. idle, creep, stop and go traffic), on account of low engine-outlet temperatures during these operating conditions. Conventional techniques to achieve elevated aftertreatment component temperatures include delayed fuel injections and over-squeezing the turbocharger, both of which result in a significant fuel consumption penalty. Cylinder deactivation (CDA) has been studied as a candidate strategy to maintain favorable aftertreatment temperatures, in a fuel efficient manner, via reduced airflow through the engine. This work focuses on prediction and demonstration of fuel economy benefits of CDA when
Joshi, MrunalGosala, DheerajAllen, CodySrinivasan, SirishRamesh, AswinVanVoorhis, MatthewTaylor, AlexanderVos, KalenShaver, GregoryMcCarthy Jr, JamesFarrell, LisaKoeberlein, Edward D.
Gasoline particulate filter (GPF) is considered a suitable solution to meet the increasingly stringent particle number (PN) regulations for both gasoline direct injection (GDI) and multi-port fuel injection (MPI) engines. Generally, GDI engines emit more particulate matter (PM) and PN. In recent years, GDI engines have gained significant market penetration in the automobile industry owing to better fuel economy and drivability. In this study, an accelerated ash loading method was tested by doping lubricating oil into the fuel for a GDI engine. Emission tests were performed at different ash loads with different driving cycles and GPF combinations. The results showed that the GPF could significantly reduce particle emissions to meet the China 6 regulation. With further ash loading, the filtration efficiency increased above 99% and the effects on fuel consumption and backpressure were found to be limited, even with an ash loading of up to 50 g/l
Hua, LunPan, JinchongMIAO, ShuxiaGu, DonglinShao, HuifangWang, YinhuiYang, FanHe, Suhao
With the implementation of the “Worldwide harmonized Light duty Test Procedure” (WLTP) and the highly dynamic “Real Driving Emissions” (RDE) tests in Europe, different engineering methodologies from virtual calibration approaches to Engine-in-the-loop (EiL) methods have to be considered to define and calibrate efficient exhaust gas aftertreatment technologies without the availability of prototype vehicles in early project phases. Since different types of testing facilities can be used, the effects of test benches as well as real and virtual vehicle operators have to be determined. Moreover, in order to effectively reduce harmful emissions, the reproducibility of test cycles is essential for an accurate and efficient application of exhaust gas aftertreatment systems and the calibration of internal combustion engines. In this paper, the influence of different human drivers on the particle count of a passenger car with a small turbocharged three-inline-cylinder gasoline engine with intake
Guse, DanielRoehrich, HenningLenz, MartinPischinger, Stefan
There is a distinct difference between plug-in hybrid electric vehicles in the market today. One key distinction that can be made is to classify a plug-in hybrid electric vehicle (PHEV) according to its operational behavior in charge depleting (CD) mode. Some PHEVs are capable of using the electric-only propulsion system to achieve all-electric operation for all driving conditions in CD mode, including full power performance. In contrast, some PHEVs, henceforth termed “blended PHEVs”, cannot satisfy the power requirements of all driving conditions with the electric-only propulsion system and occasionally utilize blended CD operation whereby it is necessary to blend the use of the internal combustion (IC) engine with the use of the electric motor(s) to help power the vehicle. This characteristic can result in a unique phenomenon where it is possible for a blended PHEV to drive for miles in electric-only mode at the start of a trip before encountering a rapid acceleration that generates
Pham, AllenJeftic, Marko
To meet US EPA light-duty vehicle emission standards, the vehicle powertrain has to be optimally controlled in addition to maintaining very high catalyst system efficiency. If vehicles are operated outside the bounds of a standard laboratory exhaust emission test (e.g., on-road or off-cycle) the operating control strategy may shift to optimize other desirable parameters such as fuel economy and drivability. Under these circumstances. The engine control system could be operating in a different state space from an emission control stand point. This control state-space can be observed based on four principal parameters: NOx, Lambda and exhaust temperature (measured at the tailpipe) and vehicle acceleration. These vehicle emission control patterns can be characterized by their corresponding emission control signatures, such as cold start, transient fuel control, and high speed/high load open loop. These emission control signatures are unique to a variety of engine technologies as well
Tang, XiaoguoCaldwell, WalterMcBryde, Dan
The scope of this SAE Information Report is to supply the user with sufficient information so that he may decide whether acoustic emission test methods apply to his particular inspection problem. Detailed technical information can be obtained by referring to Section 2
Metals Technical Committee
Control of harmful emissions during cold start of the engine has become a challenging task over the years due to the ever increasing stringent emission norms. Positioning the catalytic converter closer to the exhaust manifold is an efficient way of achieving rapid light-off temperature. On the other hand, the resulting higher thermal loading under high-load engine operation may substantially cause thermal degradation and accelerate catalyst ageing. The objective of the present work is to reduce the light-off time of the catalyst and at the same time reduce the thermal degradation and ageing of the catalyst to the minimum possible extent by adopting an approach with Dynamic Catalytic Converter System (DCCS). The emission tests were conducted at the cold start of a 4 cylinder spark ignition engine with DCCS at different positions of the catalyst at no load conditions. Also emission tests were conducted with pre-catalysts of 20% volume and 40% volume of the main catalytic converter and
Mahadevan, GanesanSubramanian, Sendilvelan
As part of an effort to shift focus from the emissions performance of pre-production prototypes in certification to the emissions performance of in-use vehicles, the US Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) instituted the “CAP 2000” program. As part of that program, manufacturers are required to retrieve customer-operated in-use vehicles and test their emissions. The EPA and CARB rules contain specific sample size and mileage criteria. The program has been in place for over 15 model years. This paper examines the in-use performance results for 3115 refueling tests, 3844 hot soak+2-day diurnal evaporative emission tests covering five sets of regulatory emission standards, and evaluates several related regulatory issues such as in-use durability and the effectiveness of evaporative on-board diagnostic (OBD) systems. The in-use verification program (IUVP) test results show very high pass rates (95%+) for refueling and evaporative emission
Passavant, Glenn W.
The aim of the present work is to analyse and compare the energetic performances and the emissions conversion capability of active and passive aftertreatment systems for lean burn engines. To this purpose, a computational one-dimensional transient model has been developed and validated. The code permits to assess the heat exchange between the solid and the exhaust gas, to evaluate the conversion of the main engine pollutants, and to estimate the energy effectiveness. The response of the systems to variations in engine operating conditions have been investigated considering standard emission test cycles. The analysis highlighted that the active flow control tends to increase the thermal inertia of the apparatus and then it appears more suitable to maintain higher temperature level and to guarantee higher pollutants conversion at low engine loads after long full load operation. Conversely, the unidirectional flow is preferable when a rapid heating (i.e., cold start, warm up phase, etc
Algieri, AngeloMorrone, PietropaoloSettino, JessicaCastiglione, TeresaBova, Sergio
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