Browse Topic: Diesel exhaust emissions

Items (886)
With emission regulations becoming increasingly stringent, the integration of Diesel Exhaust Fluid (DEF) in aftertreatment systems has become essential for reducing nitrogen oxide (NOx) emissions in compliance with these evolving standards. DEF dosing is a very critical component in Selective Catalytic Reduction (SCR) systems, where it chemically reacts with NOx in the exhaust stream to form harmless nitrogen and water vapor, thus significantly reducing the environmental impact of diesel engines. However, the introduction of DEF presents a challenge of corrosion risk within the aftertreatment system components. This study aims to predict the location of corrosion, and its risk associated with DEF usage in Diesel aftertreatment system, by employing a multi-faceted approach that includes physical testing and computational modelling. Specifically, the focus of this paper is on predicting corrosion locations from unsteady DEF spray analysis without modelling detailed corrosion chemistry
Udhane, Tushar SudamNanduru, EnochWarwick, MichaelWilley, DonaldGiri, NikhilParikh, Tanishq
As a journey to green initiatives, one of the focus areas for automotive industry is reducing environmental impact especially in case of internal combustion engines. Latest digital twin technology enable modelling complicated, fast and unsteady phenomena including the changes of emission gases concentration and output torque observed during diesel emission and combustion process. This paper presents research on the emission and combustion characteristics of a heavy vehicle diesel engine, elaborating an engineered architecture for prognostics/diagnostics, state monitoring, and performance trending of heavy-duty vehicle engine (HDVE) and after treatment system (ATS). The proposed architecture leverages advanced modeling methodologies to ensure precise predictions and diagnostics, using data-driven techniques, the architecture accurately model’s engine and exhaust system behaviors under various operating conditions. For exhaust system, architecture demonstrates encouraging predictive
Singh, PrabhsharnThakare, UjvalHivarkar, Umesh
ABSTRACT This work investigates non-traditional operating modes of a diesel engine that allow the tailoring of acoustic, smoke and thermal signatures for unique unmanned ground vehicle (UGV) military applications. A production, air-cooled single-cylinder diesel engine having a mechanical fuel injection system has been retrofit with a flexible common-rail injection and electronic control system. The experimental domain explores the effects of the injection timing and pressure on the engine’s acoustic, smoke and heat signatures through analysis of the in-cylinder combustion processes. Surface maps of loudness, exhaust temperature and exhaust smoke density over the range of fuel injection strategies are presented, illustrating the degree to which each signature may be controlled. Trade-offs between the signature modes are presented and discussed. The results demonstrate the possibility of providing military UGVs the capability to tailor their acoustic, infrared and smoke signatures
Jansons, MarcisKhaira, SukhbirBryzik, Walter
Growing environmental concerns drive the increasing need for a more climate-friendly mobility and pose a challenge for the development of future powertrains. Hydrogen engines represent a suitable alternative for the heavy-duty segment. However, typical operation includes dynamic conditions and the requirement for high loads that produce the highest NOx emissions. These emissions must be reduced below the legal limits through selective catalytic reduction (SCR). The application of such a control system is time-intensive and requires extensive domain knowledge. We propose that almost human-like control strategies can be achieved for this virtual application with less time and expert knowledge by using Deep Reinforcement Learning. A proximal policy optimization (PPO) -based agent is trained to control the injection of Diesel exhaust fluid (DEF) and compared with the performance of a manually tuned controller. The performance is evaluated based on the restrictive emission limits of a
Itzen, DirkAngerbauer, MartinHagenbucher, TimoGrill, MichaelKulzer, Andre
Morphology, nanostructure, and composition of soot extracted from the oil sump of different heavy-duty engines operated under dynamometer and field conditions were investigated. Soot characteristics were then compared to a carbon black sample. Soot was extracted from used oil for transmission electron microscopy (TEM) analysis. Energy-dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) analyses were also performed to assess soot composition. Two soot classes, I and II, can be identified based on their appearance under the TEM. Carbon black and class I particles have graphitic structures, while class II samples have a more sludge-like appearance. Similar aggregate sizes were observed among the samples. In all samples, the primary particle size distribution ranges from 16 nm to 22 nm in terms of mean diameter. Differences in the length and tortuosity of the graphitic fringes between the samples were observed. The findings suggest a greater degree of interaction between
Pacino, AndreaLa Rocca, AntoninoCairns, AlasdairFay, Michael W.Smith, JoshuaBerryman, JacquelineFowell, Mark
Reinforcement learning (RL) is a computational approach to understanding and automating goal-directed learning and decision-making. The difference from other computational approaches is the emphasis on learning by an agent from direct interaction with its environment to achieve long-term goals [1]. In this work, the RL algorithm was implemented using Python. This then enables the RL algorithm to make decisions to optimize the output from the system and provide real-time adaptation to changes and their retention for future usage. A diesel engine is a complex system where a RL algorithm can address the NOx–soot emissions trade-off by controlling fuel injection quantity and timing. This study used RL to optimize the fuel injection timing to get a better NO–soot trade-off for a common rail diesel engine. The diesel engine utilizes a pilot–main and a pilot–main–post-fuel injection strategy. Change of fuel injection quantity was not attempted in this study as the main objective was to
Vaze, AbhijeetMehta, Pramod S.Krishnasamy, Anand
Hydrogen (H2) is commonly considered as one of the most promising carbon-free energy carriers allowing for a decarbonization of combustion applications, for instance by retrofitting of conventional diesel internal combustion engines (ICEs). Although modern H2-ICEs emit only comparably low levels of nitrogen oxides (NOx), efficient catalytic converters are mandatory for exhaust gas after-treatment in order to establish near-zero emission applications. In this context, the present study evaluates the performance of a commercial state-of-the-art oxidation catalyst (OC) and of a catalyst for selective catalytic reduction (SCR) that are typically used for emission reduction from diesel exhausts under conditions representative for H2-fueled ICEs, namely oxygen-rich exhausts with high water vapor levels, comparably low temperatures, and potentially considerable levels of unburnt H2. Herein, the OC is supposed to convert H2 slippage, which can occur due to incomplete combustion, and to oxidize
Lott, PatrickSchäfer, KathrinDeutschmann, OlafWerner, ManuelWeinmann, PhilippZimmermann, LisaToebben, Heike
The proposed Euro-7 regulations are expected to build on the significant emissions reductions that have already been achieved using advanced Euro VI compliant after treatment systems (ATS). The introduction of in-service conformity (ISC) requirements during Euro VI paved the way for enabling compliance during real-world driving conditions. The diverse range of applications and resulting operating conditions greatly impact ATS design and the ability of the diesel particulate filter (DPF) to maintain performance under the most challenging boundary conditions including cold starts, partial/complete regenerations, and high passive soot burn operation. The current study attempts to map the particle number (PN) filtration performance of different DPF technologies under a variety of in-use cycles developed based on field-data from heavy duty Class-8 / N3 vehicles. Access to such performance maps can allow original equipment manufacturers (OEMs) to select DPF technologies to suit different
Viswanathan, SandeepSadek, GhadiReddy, VishalHe, SuhaoAlam, Rabeka
In this work, the impact of hexanol/diesel/biodiesel blend on engine characteristics of a common rail direct injection (CRDI) diesel engine was studied. Biodiesel is more viscous in nature and higher cetane count, hexanol has a lower viscosity and cetane count. The drawbacks of both biodiesel and hexanol can be overcome by blending both hexanol and biodiesel with diesel fuel in the right proportion. Tests were carried out using a 4-stroke CRDI engine with two cylinders. Biodiesel and 1-hexanol were blended in a ratio of 10% each by volume with diesel and compared with B10D90 and B20D80 blends. It was noted that the addition of hexanol enhances the combustion characteristics of the engine. At 20% load H10B10D80 showed71.34 bar which is highest compared to other fuels in the test. The blends had a positive effect on emissions, there was drastic reduction in NOx was noticed, also HC and CO emission was lower than diesel emissions. The lowest CO, and HC emission is obtained for H10B10D80
Santhosh, K.Shahapur, SaikumarKumar, G.N.Ravikumar, K.N.Raghavendra Reddy, N.V.
The new emission requirement norms in India calls for a robust Exhaust and After Treatment System (EATS) in automobiles. Its main purpose is to reduce the emission of harmful pollutants into the environment. EATS have a series of components that cleans the diesel exhaust emitted by the engine prior to releasing it through the tailpipe to the outside air. All the EATS components must undergo stringent testing protocol prior to its implementation in vehicle. During the exhaust treatment process, a very high temperature of about 550°C is produced in the EATS system. Hence, the effect of this higher temperature needs to be considered for validation. Moreover, the components will undergo multi-axial vibration in real road conditions which also need to be simulated during validation. In addition, engine vibrations are directly transmitted through a flex bellow to EATS system. These vibrations need to be captured and simulated in component level testing. In this paper, we detailed on various
Sundarrajan, ManikandanNarasimman, Obuli KarthikeyanNagarajan, GopikannanRajaraman, ManikandanR, Suresh
The major objective of this paper is to develop thermal management strategy targeting optimum performance of Selective Catalytic Reduction (SCR) catalyst in a Medium Duty Diesel Engine performing in BS6 emission cycles. In the current scenario, the Emissions Norms are becoming more stringent and with the introduction of Real Drive Emission Test (RDE) and WHTC test comprising of both cold and hot phase, there is a need to develop techniques and strategies which are quick to respond in real time to cope with emission limit especially NOx. SCR seems to be suitable solution in reducing NOx in real time. However, there are limitations to SCR operating conditions, the major being the dosing release conditions which defines the gas temperature at which DEF (Diesel Exhaust Fluid) can be injected as DEF injection at lower gas temperatures than dosing release will lead to Urea deposit formation and will significantly hamper the SCR performance. The second factor for optimum SCR operation is to
Sharma, Ajeet KumarKreuzig, GerhardGupta, AyushGoyal, DineshGarg, Varun
In the Journey towards Zero Emission and decarbonization, with emerging advancement in technology form current BS6 to near future EURO7 standards of emission, these emission norms are achievable when we amalgamate with an assistive technology of Electrically Heated System for thermal management in Diesel emission control i.e., called CatVap®. With the increasingly stringent limits on vehicle pollutants- including NOx emission levels are fulfilled with Twin Urea Dosing mechanism. These comprehensive lists of advanced technology to converge lowest NOx emissions without increasing CO2 emissions. The Major effort in the existing structure is to accelerate the SCR temperature and enhance the conversion efficiency of NOx in Real Drive Emission during cold start and low load duty cycle. CatVap®system provides sufficient thermal energy to facilitate rapid heating in the course of low load cycles and cold city rides for efficient gas conversion. As they are used to accelerate the light-off
YS, AnanthkumarK, SabareeswaranM, Jayashree
Controlling NOx emission demand is getting more severe with Euro 7 legislation. In turn, this brings more focus on SCR (Selective Catalytic Reduction) technology, which uses a eutectic mixture of Urea (32.5%)– Water (67.5%) solution, more popularly known as Diesel Exhaust Fluid (DEF/ AdBlue®). Under extreme winter conditions, AdBlue® freezes as the ambient reaches below the freezing point (-11°C). Due to Legislation requirements (EU), estimating the time required to thaw a desired volume of frozen AdBlue® using forced heating is a matter of interest, leading to the concept of overall Melting/Thawing performance. So far, testing has been the primary method for arriving at a suitable melting mechanism and for designing electrical coils or hot coolant lines, which is expensive. This paper proposes a novel digital method using the 3D CFD tool STAR CCM+ to study the melting behavior of AdBlue®. The method is characterized by capturing phase change using the popular multiphase (VOF) approach
Govindarajan, VaishaliVarughese, ShibuBanik, SoumenduR, Vineeth
Diesel Exhaust Fluid (DEF) concentration monitoring is done to detect the concentration at which the emission thresholds are exceeded in BSVI engines [1]. This paper introduces a novel method to model the fault monitoring system with enable conditions designed to detect deterioration in DEF concentration, while reducing misdetection. This eliminates the need for dedicated sensor, reduces complexity, cost, and potential sensor-related failure modes. Traditionally, Diesel Exhaust Fluid quality sensors have been employed to measure the absolute concentration of Diesel Exhaust Fluid in the aqueous solution of urea [2]. This information is used to detect usage of poor quality DEF which results in increase in NOx emission beyond legal limits. The proposed method leverages the strong relationship between catalyst conversion efficiency and Diesel Exhaust Fluid concentration for modelling a fault monitoring system which also takes inputs from various other sensors, to make the system fault
Venkat, HarishKumar, Gokul ElumalaiKumar, KosalaramanG, Vijayakumar
Decades ago, like the 1990s automobile industry, the off-highway industry was purely recognized as a mechanical entity. In the mechanical system, accuracy and troubleshooting of faults were significant concerns. Additionally, the continuous stringent emission norms by the government call for the adaptation of the aftertreatment and DeNOx led to more complexity and challenges. To meet the government emission regulation and product performance, thorough functionality testing of manufactured units was crucial. For this purpose, EOL/diagnostics testers are developed. Diagnostic protocol CAN establish the connection between ECU and tester due to its robustness and data handling capabilities. This paper aims to develop and test the end-of-line (EOL) tester for off-highway diesel engines. The communication between the tester and ECU will be over UDSonCAN, conforming to standard ISO14229. This tester will cover the synchronization of various components used to assemble the engine and maintain
Khond, Nikita AnilGandhi, NareshKakade, Suhas
Selective Catalytic Reduction (SCR) operation depends strongly on both heat and ammonia availability (stored or incoming). These requirements make high efficiency SCR challenging in lower temperature cycles where SCR is relatively cold, and Diesel Exhaust Fluid (DEF) injection is largely absent due to deposit risks. Examples include low temperature cycles such as low-idling, stop-and-go or low-load cycles such as city driving or local delivery cycles. An Electrically Heated Mixer/ EHM™ is utilized to address these challenges in a single component. EHM simultaneously provides heat for rapid SCR heat-up during the cold phase or in other low-temperature operations, steady or transient. Second, its heating mechanism makes deposit risks nearly non-existent. Third, EHM enables DEF injection at 130 °C, markedly enhancing the low temperature SCR impact. It is shown that these capabilities collectively make EHM a promising pathway for meeting ultra-stringent NOx targets including California
Masoudi, MansourPoliakov, NickNoorfeshan, Sahm
The negative effects of long-term exposure to soot and particulate matter emissions from diesel exhaust on the human health have been widely acknowledged due to the harmful substances that exhaust gas contains. Regulators have established strict programs to determine the performance and reliability of emissions after-treatment systems and devices. Tests were conducted to evaluate the efficacy of three diesel particulate filter (DPF) cleaning methods: 1) thermal and pneumatic cleaning, 2) ultrasonic cleaning, and 3) aqueous cleaning methods. A novel non-destructive method to quantify soot and ash deposits in the filters was developed, validated and used to determine the effectiveness of the identified cleaning methods. Given the number of different cleaning methods available, testing against a set of standard parameters provided accurate comparative results. Test results showed at least satisfactory ratings for all cleaning systems that were evaluated, while two systems stood out with
Bonsi, Adime KofiSurcel, Marius-DorinSzathmary, Gabor
Upcoming, stricter diesel exhaust emissions standards will likely require aftertreatment architectures with multiple diesel exhaust fluid (DEF) introduction locations. Managing NH3 slip with technologies such as an ammonia slip catalyst (ASC) will continue to be critical in these future aftertreatment systems. In this study, we evaluate the impact of SO2 exposure on a state-of-the-art commercially available ASC. SO2 is co-fed at 0.5 or 3 ppmv to either approximate or accelerate a real-world exhaust SO2 impact. ASC performance during sulfur co-feeding is measured under a wide variety of simulated real-world conditions. Results indicate that the loss of NO conversion during SCR is dependent on the cumulative SO2 exposure, regardless of the inlet SO2 concentration. Meanwhile, N2O formation under SCR conditions is nonlinearly affected by SO2 exposure, with formation increasing during 0.5 ppmv SO2 exposure but decreasing in the presence of 3 ppmv SO2. TPO experiments reveal the formation of
Ottinger, NathanXi, YuanzhouKiani, DaniyalLiu, Z. Gerald
Exhaust Gas Recirculation (EGR) coolers are widely used on diesel engines to reduce in-cylinder NOx formation. A common problem is the accumulation of a fouling layer inside the heat exchanger, mainly due to thermophoresis that leads to deposition of particulate matter (PM), and condensation of hydrocarbons (HC) from the diesel exhaust. From a recent investigation of deposits from field samples of EGR coolers, it was confirmed that the densities of their deposits were much higher than reported in previous studies. In this study, the experiments were conducted in order to verify hypotheses about deposit growth, especially densification. An experimental set up which included a custom-made shell and tube type heat exchanger with six surrogate tubes was designed to control flow rate independently, and was installed on a 1.9 L L-4 common rail turbo diesel engine. The test cycle and conditions were higher PM/ lower HC with 75°C coolant temperature for 1.5h, then lower PM/ higher HC with 75°C
Tomuro, MinatoBhadra, KaustavHebert, JasonBoehman, Andre
This specification describes a method and acceptance criteria for testing automotive wire harness retainer clips. Retainer clips are plastic parts that hold a wire harness or electrical connector in a specific position. Typical plastic retainers work by having a set of “branches” that can be inserted into a hole sized to be easy to install but provide acceptable retention. This specification tests retainer clips for mechanical retention when exposed to the mechanical and environmental stresses typically found in automotive applications over a 15-year service life. This specification has several test options to allow the test to match to the expected service conditions. The variability of applications typically arises from different ambient temperatures near the clip, different proximity to automotive fluids, different exposure to standing water or water spray, and different thicknesses of the holes that the clip is inserted into. Clips are typically inserted into sheet or rolled metal
USCAR
Commercial vehicles require advanced engine and aftertreatment (AT) systems to meet upcoming nitrogen oxides (NOx) and carbon dioxide (CO2) regulations. This article focuses on the development and calibration of a model-based controller (MBC) for an advanced diesel AT system. The MBC was first applied to a standard AT system including a diesel particulate filter (DPF) and selective catalytic reduction (SCR) catalyst. Next, a light-off SCR (LO-SCR) was added upstream of the standard AT system. The MBC was optimized for both catalysts for a production engine where the diesel exhaust fluid (DEF) was unheated for both SCRs. This research shows that the tailpipe (TP) NOx could be reduced by using MBC on both catalysts. The net result was increased NOx conversion efficiency by one percentage point on both the LO-SCR and the primary SCR. The CO2 emissions were slightly reduced, but this effect was not significant. Finally, the MBC was used with a final setup representative of future AT
Meruva, PrathikMatheaus, AndrewZavala, BryanSharp, Christopher A.McCarthy Jr., James E.
The Coordinating Research Council (CRC) is actively involved in developing and applying advanced analytical techniques to the chemical characterization of transportation fuels. This article complements a 2017 CRC project to quantify and compare the effects of a commercially available renewable diesel fuel (hydrotreated vegetable oil [HVO]) and an ultralow sulfur diesel (ULSD) fuel on engine-out gaseous and particulate matter (PM) emissions from a light-duty vehicle. Results showed that the combustion of HVO fuel had an advantage over ULSD in terms of lowering engine-out emissions (THC, CO, NOx, etc.). Furthermore, this advantage is strongly related to the fuel composition. This article summarizes the results of advanced and comprehensive analytical tests on the same ULSD and HVO fuels and attempts to connect some of the engine-out emissions results to fuel composition and specific chemical structures. A variety of test methods, generally unavailable in combination, were employed, such
Bays, J. TimothyGieleciak, RafalViola, Michael B.Lewis, Russ P.Cort, John R.Campbell, Kristen B.Coffey, Gregory W.Linehan, John C.Kusinski, Matthew
Governments and regulatory agencies in North America are evaluating the nitrogen oxides (NOx) emissions of heavy-duty on-road vehicles to effectively regulate these emissions in order to improve public health and meet air quality requirements. This paper provides results from real-world Class 8 tractor-trailer truck activity and emissions data gathering conducted in the Northeast and Mid-Atlantic United States. Unlike some other areas of the United States (US), there is little available data on in-use operation and emissions performance from heavy-duty trucks in this region where temperatures can be consistently cold in winter. The purposes of this study are to add to the literature on real-world truck operation and emissions in the Northeast and Mid-Atlantic regions; to analyze the captured emissions data using recently established calculation methods implemented by the California Air Resources Board (CARB), which have not yet been applied to data from this region; and to assist air
Humphries, KieranCooper, CoralieAhmadi, Mahdi
Using a compression engine with dual fuel is the most promising technology to control emissions and for fuel economy, to meet the upcoming legislative norms. This experimental study was conducted to understand the effect of fuel reactivity on engine performance and emission in a compression ignition (CI) engine. The effect of injection timing, gasoline ratio, and exhaust gas recirculation (EGR) rate on emission is compared to the conventional diesel engine. In this study, high-octane fuel (gasoline) is injected manifold the intake of a diesel engine (high-reactivity fuel) to primarily investigate the effects of balance between fuels having low and high reactivity. Fuel reactivity is optimized on different load and speed conditions by varying the diesel and gasoline quantity. Experimental results indicate that dual fuel helps to avoid nitrogen oxides (NOx) and soot trade-off, mitigating both to near-zero values. The engine was tested at a constant speed of 1520 rpm and showed a
Barman, JyotirmoyDeshmukh, Devendra
Low temperature Diesel exhaust operations such as during low-load cycles are some of the most difficult conditions for SCR of NOx. This, along with newer regulations targeting substantial reduction of the tailpipe NOx such as California-2024/2027 NOx regulations, adds to challenges of high efficiency SCR of NOx in low temperature operations. A novel design, low-cost, low-energy Electrically Heated Mixer (EHM™), energized via the 12, 24 or 48 V vehicle electrical system, is used to accelerate formation of reductants (ammonia, isocyanic acid) in low temperature exhaust (low load cycles), so to enable high efficiency SCR of NOx in most challenging SCR conditions, while also mitigating urea deposit formation. EHM™ is also used to heat the cooler exhaust flow during engine cold-start. It easily fits common exhaust configurations and can be utilized on light, medium or heavy duty Diesel aftertreatment systems, on- or non-road or in stationary systems
Masoudi, MansourPoliakov, NickNoorfeshan, Sahm
This SAE Standard defines the test conditions, procedures, and performance requirements for circuit breakers in ratings up to and including 200 A. The document includes automatic reset, modified reset, and manually reset types of circuit breakers for 12 VDC, 24 VDC, and 48 VDC electrical systems. Some circuit breakers may have dual voltage ratings (AC and DC); however, this document evaluates DC performance only
Truck and Bus Electrical Systems Committee
This paper analyzes the use of an ammonia sensor for feedback control in diesel exhaust systems. We build our case around the specific example of the heavy duty transient cycle, and an exhaust system with an SCR catalyst, a single urea injector and an upstream and downstream NOx sensor. A key component in our analysis is the inclusion of the tolerance of the ammonia sensor. We show that with the current understanding of the sensor tolerance, the ammonia sensor has limited benefit for controls
Van Nieuwstadt, Michiel
Selective Catalytic Reduction (SCR) is a process where one injects an aqueous solution of urea into a diesel exhaust system in order to reduce NOx emissions. The urea solution known as AdBlue® or Diesel Exhaust Fluid (DEF) is stored in a DEF Tank that can under cold weather conditions freeze over. Since AdBlue® is unusable while frozen, we use heaters installed in the tanks to melt AdBlue® with government regulations mandating time required to melt AdBlue® in the tank. In this article, we investigate whether a CFD (Computational Fluid Dynamics) based methodology can accurately evaluate time required in melting AdBlue® for a given DEF Tank and heater coil design for a production vehicle as per standard testing procedure. Simulations used a coupled methodology with PowerFLOW® as the flow solver and PowerTHERM® as the thermal solver. The flow simulation did require an accurate modelling of phase change from solid to liquid for AdBlue®. We observe excellent agreement between test data and
Mukutmoni, Devadattakandasamy, SatheeshTabacchi, DilettaScotti, MarcoCrippa, LucaFilippova, OlgaZhou, Chong
The commercial vehicle industry continues to move in the direction of improving brake thermal efficiency while meeting more stringent diesel engine emission requirements. This study focused on demonstrating future emissions by using an exhaust burner upstream of a conventional aftertreatment system. This work highlights system results over the low load cycle (LLC) and many other pertinent cycles (Beverage Cycle, and Stay Hot Cycle, New York Bus Cycle). These efforts complement previous works showing system performance over the Heavy-Duty FTP and World Harmonized Transient Cycle (WHTC). The exhaust burner is used to raise and maintain the Selective Catalytic Reduction (SCR) catalyst at its optimal temperature over these cycles for efficient NOX reduction. This work showed that tailpipe NOX is significantly improved over these cycles with the exhaust burner. In certain cases, the improvements resulted in tailpipe NOX values well below the adopted 2027 LLC NOX standard of 0.05 g/hp-hr
McCarthy, Jr., JamesMatheaus, AndrewZavala, BryanSharp, ChristopherHarris, Thomas
For the NOx removal from diesel exhaust, the selective catalytic reduction (SCR) and lean NOx traps are established technologies. However, these procedures lack efficiency below 200 °C, which is of importance for city driving and cold start phases. Thus, the present paper deals with the development of a novel low-temperature deNOx strategy implying the catalytic NOx reduction by hydrogen. For the investigations, a highly active H2-deNOx catalyst, originally engineered for lean H2 combustion engines, was employed. This Pt-based catalyst reached peak NOx conversion of 95 % in synthetic diesel exhaust with N2 selectivities up to 80 %. Additionally, driving cycle tests on a diesel engine test bench were also performed to evaluate the H2-deNOx performance under practical conditions. For this purpose, a diesel oxidation catalyst, a diesel particulate filter and a H2 injection nozzle with mixing unit were placed upstream to the full size H2-deNOx catalyst. As a result, the Worldwide
Esser, EnnoKureti, SvenHeckemüller, LukasTodt, ArneEilts, PeterMorawietz, TobiasFriedrich, AndreasWaiblinger, WendelinHosseiny, SchwanBunar, Frank
Heavy Duty Vehicle (HDV) Diesel emission regulations are set to be tightened in the future. The introduction of PN PEMS testing for Euro VI-e, and the expected tightening of PM/NOx targets set to be introduced by CARB in the US beyond 2024 are expected to create challenging tailpipe PN conditions for OEMs. Additionally, warranty and the useful life period will be extended from current levels. Improved fuel efficiency (reduction of CO2) also remains an important performance criteria. Furthermore, future non-road diesel emission regulations may follow tighten HDV diesel emission regulations contents, and non-road cycles evaluation needs to be considered as well for future. In response to the above tightened regulation, for Diesel Particulate Filter (DPF) technologies will require higher PN filtration performance, lower pressure drop, higher ash capacity and better pressure drop hysteresis for improved soot detectability. Additionally, thermal management of aftertreatment system has
Kurimoto, YudaiMishina, RitsukoKato, KyoheiAoki, TakashiHonda, TakahiroKaneda, AtsushiVogt, Claus Dieter
The urea-selective catalyst reduction system implemented in commercial vehicles facilitates ensuring compliance with the NOx regulation limit. A significant challenge in urea injection is to comprehend its decomposition chemistry that often leads to the formation of unfavorable deposits in the exhaust system unit. Due to the complex interaction of the multiphase fluid flow and transport processes, a significant degree of uncertainty is associated with the identification of the interacting factors that control the deposit initiation and their growth. A systematic investigation was conducted through numerous experiments to study the factors controlling the urea deposit that guide innovation for new product development. For the first time, the effect of pressure on urea deposits was investigated by heating an aqueous urea solution in a closed system maintained between 30 and 200 psi. Chemical characterization procedure was conducted using liquid chromatography-multiple reaction monitoring
Alembath, AnandSmith, Joseph D.Mooney, BrianShinde, AtulShashidhara, Rajashekharaiah
Conventional methods of physicochemical models require various experts and a high measurement demand to achieve the required model accuracy. With an additional request for faster development time for diagnostic algorithms, this method has reached the limits of economic feasibility. Machine learning algorithms are getting more popular in order to achieve a high model accuracy with an appropriate economical effort and allow to describe complex problems using statistical methods. An important point is the independence from other modelled variables and the exclusive use of sensor data and actuator settings. The concept has already been successfully proven in the field of modelling for exhaust gas aftertreatment sensors. An engine-out nitrogen oxide (NOX) emission sensor model based on polynomial regression was developed, trained, and transferred onto a conventional automotive electronic control unit (ECU) and also proves real-time capability. Within this study several approaches are
Moser, MarcoKipping, SteveHiguchi, KazuhiroHirayama, Hiroyuki
This paper discusses the development of an all speed governed diesel-natural gas dual fuel engine for agricultural farm tractor. A 45 hp, 2.9 liters diesel-natural gas dual fuel engine with a novel closed loop secondary fuel injection system was developed. A frugal approach without any modification of the base mechanical diesel fuel injection system was followed. This approach helped to minimize the cost impact, while meeting performance and emissions at par with neat diesel operation. Additional cost on gas injection system is redeemed by cost savings on diesel fuel. The dual fuel technology developed by Mahindra & Mahindra Ltd., substitutes on an average approximately 40% of diesel with compressed natural gas, meeting the TREM III A emission norms for dual fuel while meeting all application requirements. The governing performance of the tractor was found to be superior than base diesel tractor. A prototype dual fuel tractor was tested for all field applications including puddling
Raj, Ashwin SNagarajan, VigneshwaranNISSANGI, JOY KUMARElango, VikneshRajamani, ParthibanS K, RAVINDRA
To avoid frequent regeneration intervals leading to expeditious ageing of the catalyst and substantial fuel penalty for the owner, it is always desired to estimate the soot coming from diesel exhaust emission, the soot accumulated and burnt in the Diesel Particulate Filter (DPF). Certain applications and vehicle duty cycles cannot make use of the differential pressure sensor for estimating the soot loading in the DPF because of the limitations of the sensor tolerance and measurement accuracy. The physical soot model is always active and hence a precise and more accurate model is preferred to calibrate & optimize the regeneration interval. This paper presents the approach to estimate the engine-out soot and the accumulated soot in the DPF using a graphical calculation tool (AVL Concerto CalcGraf™). The tool reduces the efforts of driving different duty cycles multiple times on the testbed and recurrent vehicle trips for data collection while calibrating the soot models, hence saving
Gaur, Kunalparashar, Shalabhvos, BasKusumba, Manoj
Commercial vehicles are moving in the direction of improving brake thermal efficiency while also meeting future diesel emission requirements. This study is focused on improving efficiency by replacing the variable geometry turbine (VGT) turbocharger with a high-efficiency fixed geometry turbocharger. Engine-out (EO) NOX emissions are maintained by providing the required amount of exhaust gas recirculation (EGR) using a 48 V motor driven EGR pump downstream of the EGR cooler. This engine is also equipped with cylinder deactivation (CDA) hardware such that the engine can be optimized at low load operation using the combination of the high-efficiency turbocharger, EGR pump and CDA. The exhaust aftertreatment system has been shown to meet 2027 emissions using the baseline engine hardware as it includes a close coupled light-off SCR followed by a downstream SCR system. A parametric analysis for improving engine efficiency is provided using the high-efficiency turbocharger, EGR pump and CDA
Bitsis, Daniel ChristopherMatheaus, AndrewHopkins, JustinMcCarthy, Jr., James E.
This SAE Recommended Practice describes the recommended methods for testing flexible harness coverings for use on ground vehicle electrical distribution systems. This SAE Recommended Practice shall apply to all tapes, extruded tube, and textile tube
Harness Covering Standards Committee
Diesel engine exhaust poses an ongoing threat to human health as well as to the environment. Automotive exhaust treatment systems have been developed over the years to reduce the large amount of diesel particulate matter (DPM) released to the atmosphere. Current systems can be categorized as selective catalytic reduction, catalytic converters, and diesel particulate filters. This study presents an emission system that focuses on the removal of exhaust particles using Brownian diffusion of DPM toward fog drops followed by cyclonic separation of DPM rich fog drops. The experimental system consisted of a 13.2 kW diesel engine, heat exchanger to cool the exhaust to saturation temperature, ultrasonic fogger, cyclone separator, and recovery of waste particulate. Representative emission tests have been performed at five different diesel engine speeds and corresponding crankshaft loads. The scavenging coefficient as measured by the particle number concentration is 0.4-0.65 without fog and 0.6
Chowdhury, Shoab AhmedDasgupta, SagarSaylor, J. R.Wagner, John
Particulate matter (PM) and NOX are two major pollutants generated by diesel engines. Modern diesel aftertreatment systems include selective catalytic reduction (SCR) technology that helps reduce tailpipe NOX emissions when coupled with diesel exhaust fluid (DEF/urea) injection. However, this process also results in the formation of urea derived byproducts that can influence non-volatile particle number (PN) measurement conducted in accordance with the European Union (EU) Particle Measurement Program (PMP) protocol. In this program, an experimental investigation of the impact of DEF injection on tailpipe PN and its implications for PMP compliant measurements was conducted using a 2015 model year 6.7 L diesel engine equipped with a diesel oxidation catalyst, diesel particulate filter and SCR system. Open access to the engine controller was available to manually override select parameters. Ammonia-to-NOX (ANR) ratio was varied to understand the impact of urea injection rate on measured
Legala, AdithyaPremnath, VinayChadwell, MichaelWeber, PhillipKhalek, Imad
Diesel Exhaust Fluid (DEF) systems are required to function in cold ambient temperatures below the freezing point of DEF. Manufacturers may demonstrate compliance by following an EPA guidance procedure described below [2], using whole vehicles at winter test sites at −18 deg C or lower. However, commercial trucks may have multiple variants with different DEF system layouts, so it is impractical to test every possible configuration. A climatic chassis dynamometer (CCD) can also be used for this test, but this is still expensive and time consuming, and does not address the problem of complexity. Instead, much time and expense can be saved by using simulation methods to identify worst case configurations, and to demonstrate with confidence that a limited number of tests will cover the whole possible range. This methodology can further be used to show that a range of vehicles can be represented with selected rig tests in a cold chamber. Such a methodology depends on the ability to generate
Vermiglio, Ezio N.De Salis, RupertClark, Kent
Cu-SSZ-13 selective catalytic reduction (SCR) catalysts are broadly applied in diesel aftertreatment systems for the catalytic conversion of oxides of nitrogen (NO + NO2). Diesel exhaust contains a wide range of water vapor concentrations depending on the operating condition. In this study, we evaluate the impact of water vapor on the relevant SCR catalytic functions including NOx conversion, NO oxidation, NH3 oxidation, and N2O formation under both standard and fast SCR conditions. Reactor-based experiments are conducted in the presence and absence of water vapor. Results indicate that water vapor can have both a positive and negative impact on low temperature NOx conversion for standard SCR reaction. At low inlet NOx concentrations, the presence of water vapor has a negative effect on NOx conversion, whereas, at high inlet NO concentrations, water vapor improves NOx conversion. At high temperatures, water vapor has a beneficial effect on NOx conversion at all NOx inlet concentrations
Ottinger, NathanXi, YuanzhouKeturakis, ChristopherLiu, Z. Gerald
Diesel engines are the primary power source for the medium and heavy-duty truck applications in the US. There is a wide range of regulatory developments being considered in the US that would impact the field of diesel engines and aftertreatment systems, such as the California Air Resources Board’s (CARB) low NOX standards and the extended durability requirement for aftertreatment systems. The proposed durability standards would require manufacturers to develop aftertreatment systems targeting up to 800,000 miles of full useful life (FUL) for Heavy heavy-duty (HHD) Application. Robust design and validation of aftertreatment systems is critical to ensure compliance with such stringent regulations. Several methodologies are being considered by the regulatory agencies for the compliance validation process, including the option of accelerated aging of the aftertreatment systems for a portion of the FUL. Performing FUL aging on an engine platform can be both technically challenging and
Thakral, NishantPremnath, VinayKhalek, ImadWaez, Mir SelimanEakle, Scott
In North America, heavy-duty diesel engines for on-road use have to meet strict regulations for their emissions of nitric oxide and nitrogen dioxide (cumulatively referred to as ‘NOx’) besides other criteria pollutants. Over the next decade, regulations for NOx emissions are expected to becoming more stringent in North America. One of the major technical barriers for achieving in-use NOx emissions commensurate with the levels determined from in-laboratory test procedures required by regulations is controlling NOx emissions during cold start and engine idling. Since the exhaust gas temperature can be low during these conditions, the effectiveness of the exhaust after-treatment (EAT) system may be reduced. Under colder climate conditions like in Canada, the impact may be even more significant. In the experimental study of this paper, certain engine operation parameters such as the fuel injection timing, fuel injection frequency per cycle, engine speed, and exhaust gas recirculation (EGR
Dev, ShouvikGuo, HongshengLiko, BrianLafrance, SimonConde, Aaron
The measurement of solid particles down to 10 nm is being incorporated into global technical regulations (GTR). This study explores the measurement of solid particles below 23 nm by using both current and proposed particle number (PN) systems having different volatile particle remover (VPR) methodologies and condensation particle counter (CPC) cutoff diameters. The measurements were conducted in dynamometer test cells using ten diesel and eight natural gas (NG) engines that were going under development for a variety of global emission standards. The PN systems measured solid PN from more than 700 test cycles. The results from the preliminary campaign showed a 10-280% increase in PN emissions with the inclusion of particles below 23 nm. In the main campaign of this study, with the utilization of the current PN system and an add-on CPC to measure sub-23 nm particles, results showed the sub-23 nm fraction averaged between 23-58% and 19-51% of the total particles for diesel and NG engines
Khan, M. YusufPeng, WeihanScott, NathanLin, YueLiew, Chet MunBowman, John P.Phillips, J. AdamRahman, MontajirWilliams, ChristopherElzey, SherrieSalemme, Tina L.
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