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Viewing 1 to 30 of 21876
2017-03-28
Technical Paper
2017-01-0638
Neerav Abani, Nishit Nagar, Rodrigo Zermeno, Michael chiang, Isaac Thomas
Heavy-duty vehicles, currently the second largest source of fuel consumption and carbon emissions are projected to be fastest growing mode in transportation sector in future. There is a clear need to increase fuel efficiency and lower emissions for these engines. The Achates Power Opposed-Piston Engine has the potential to address this growing need. In this paper, results will be presented for a 9.8L three-cylinder OP Engine that shows the potential of achieving 51%+ brake thermal efficiency (BTE), while simultaneously satisfying 4.0 g/kWhr engine out NOx and 0.01 g/kWhr engine-out soot. The OP Engine architecture can meet this performance without the use of additional technologies such as thermal barrier coatings, waste heat recovery or additional turbo-compounding.
2017-03-28
Technical Paper
2017-01-1274
Jason M. Luk, Hyung Chul Kim, Robert De Kleine, Timothy J. Wallington, Heather L. MacLean
This study investigates the life cycle greenhouse gas (GHG) emissions of a set of vehicles using two real-world gliders (vehicles without powertrains or batteries); a steel-intensive 2013 Ford Fusion glider and a multi material lightweight vehicle (MMLV) glider that utilizes significantly more aluminum and carbon fiber. These gliders are used to develop lightweight and conventional models of internal combustion engine vehicles (ICV), hybrid electric vehicles (HEV), and battery electric vehicles (BEV). Our results show that the MMLV glider can reduce life cycle GHG emissions despite its use of lightweight materials, which can be carbon intensive to produce, because the glider enables a decrease in fuel (production and use) cycle emissions. However, the fuel savings, and thus life cycle GHG emission reductions, differ substantially depending on powertrain type. Compared to ICVs, the high efficiency of HEVs decreases the potential fuel savings.
2017-03-28
Technical Paper
2017-01-0601
Huayi Li, Kenneth Butts, Kevin Zaseck, Dominic Liao-McPherson, Ilya Kolmanovsky
The development of advanced model-based engine control strategies, such as economic model predictive control (eMPC) for diesel engine fuel economy and emission optimization, requires accurate and low-complexity models for online prediction and controller validation. This paper presents the NOx and smoke emissions modeling of a light duty diesel engine equipped with a variable geometry turbocharger (VGT) and a high pressure exhaust gas recirculation (EGR) system. Such emission models can be integrated with an existing air path model into a complete engine mean value model (MVM), which can predict engine behavior at different operating conditions for controller design and validation before physical engine tests. The NOx and smoke emission models adopt an artificial neural network (ANN) approach with multi-layer perceptron (MLP) architectures. The networks are trained and validated using experimental data collected from engine bench tests.
2017-03-28
Technical Paper
2017-01-0964
Jakob Heide, Mikael Karlsson, Mireia Altimira
Selective Catalytic Reduction (SCR) of NOx through injection of Urea-Water-Solution (UWS) into the hot exhaust gas stream is an effective and extensively used strategy in internal combustion engines. Even though actual SCR systems have 95-96% de-NOx efficiency over test cycles, real driving emissions of NOx are much higher, hence proving that there is room for improvement. The efficiency of the NOx conversion is highly dependent on the size of UWS droplets and their spatial distribution. These factors are, in turn, mainly determined by the spray characteristics and its interaction with the exhaust gas flow. The main purpose of this study is to numerically investigate the sensitivity to the modelling framework of the evaporation and mixing of the spray upstream of the catalyst. The dynamics of discrete droplets is handled through the Lagrangian Particle Tracking framework, with models that account for droplet breakup and coalescence, turbulence effects, and water evaporation.
2017-03-28
Technical Paper
2017-01-0141
Ray Host, Peter Moilanen, Marcus Fried, Bhageerath Bogi
Future vehicle North American emissions standards (e.g., North American SULEV 30) require the exhaust catalyst to be >80% efficient by 20 seconds after the engine has been started in the Federal Test Procedure. Turbocharged engines are especially challenged to deliver fast catalyst lightoff since the presence of the turbocharger in the exhaust flow path significantly increases exhaust system heat losses. A solution to delivering cost effective SULEV30 emissions in turbocharged engines is to achieve fast catalyst light-off by reducing exhaust system heat losses in cold start, without increasing catalyst thermal degradation during high load operation. A CAE methodology to assess the thermal performance of exhaust system hardware options, from the exhaust port to the catalyst brick face is described, which assures compliance with future emissions regulations.
2017-03-28
Technical Paper
2017-01-0645
Jeremy Galpin, Thierry Colliou, Olivier Laget, Fabien Rabeau, Gaetano De Paola, Pascal Rahir
In spite of the increasingly stringent emission standards, the constant growth of road traffic contributes to climate change and induces detrimental effects on the environment. The European REWARD project (REal World Advanced Technologies foR Diesel Engines) aims to develop a new generation of Diesel engines complying with stricter post Euro 6 legislation and with lower CO2 emissions. Among the different technologies developed, a fuel-efficient two-stroke Diesel engine suited for C-segment passenger cars will be designed and experimentally evaluated. One major challenge for two-stroke engines is the achievement of an efficient scavenging. As the emptying of the in-cylinder burnt gases and the filling by fresh gases is performed in the same time, the complexity consists in removing as much as burnt gases as possible while avoiding the by-pass of fresh air toward the exhaust line.
2017-03-28
Technical Paper
2017-01-0682
Yuedong Chao, Haifeng Lu, Zongjie Hu, Jun Deng, Zhijun Wu, Liguang Li, Yuan Shen, Shuang Yuan
In this paper comparisons were made between the fuel economy improvement by a High Pressure (HP) water-cooled Exhaust Gas Recirculation (EGR) system and that by a Low Pressure (LP) water-cooled EGR system. Experiments were implemented on a 1.3-Litre turbocharged PFI gasoline engine from 1500rpm to 3000rpm and BMEP from 2bar to 14bar because of the relative narrow available range of HP-EGR system. In consideration of practical application of EGR system, the coolant used in this experiment was kept almost the same temperature as in real vehicles (88±3℃) instead of underground water temperature. The results indicated that, HP-EGR usually got higher best EGR rates for fuel economy at low-load region, and a better improvement (up to 2.96%) of fuel economy was expected. In contrast at moderate-to-high loads, especially at low speed high load region, HP-EGR rates were severely constrained by the application of turbo.
2017-03-28
Technical Paper
2017-01-0966
Jana Aslanjan, Christian Klauer, Cathleen Perlman, Vivien Günther, Fabian Mauss
The importance to reduce automotive exhaust gas emissions is constantly increasing. Not only the country-specific laws or regulations are getting more stringent also the global increase of automobiles is requiring a responsible handling of the issue. The three-way-catalytic converter (TWC) is one of the most common catalysts for the engine exhaust gas after treatment. The reduction of CO, NO and unburned hydrocarbons is fulfilled via oxidation of carbon monoxide and hydrocarbons, and reduction of nitrogen oxides. These conversion effects were simulated in previous works using single channel approaches [e.g. Fröjd/Mauss, SAE International 2011-01-1306] and detailed kinetic models [e.g Chatterjee et al., Faraday Discussions 119 (2001) 371-384 and Koop et al., Appl. Catal.B: Environmental 91 (2009), 47-58]. Single channel and multiple representative catalyst channel models are used in this work. Heat losses in between the catalyst are considered with the multi-channel approach.
2017-03-28
Technical Paper
2017-01-0675
Kenichiro Ogata
Application of low pressure cooled EGR to suppress engine knock is increasing because of advantages of engine downsizing, high compression ratio. Purpose of this study is to develop ignition system to extend EGR limit. This paper summarizes the experimental result obtained by using reinforce conventional ignition coil. As engine speed (mixture flow velocity between plug-gap) and EGR ratio were increased, secondary energy requirement of ignition coil was increased. The results show effectiveness of high energy ignition system for extending EGR area.
2017-03-28
Technical Paper
2017-01-0740
Yu Zhang, Yuanjiang Pei, Nayan Engineer, Kukwon Cho, David Cleary
Partially-premixed combustion (PPC) enabled through gasoline Compression Ignition (GCI) shows a promising potential to achieve high fuel efficiency with low engine-out oxides of nitrogen (NOx) and particulate matter (PM) emissions. However, it faces technical barriers to meet the need for simultaneously mitigating combustion efficiency loss at low load as well as containing maximum pressure rise rate (MPRR) and soot at high load. In addition, GCI typically requires high EGR rate at medium-to-high load and therefore poses challenges on the air system development and transient engine operation. The current study aims to utilize 3-D computational fluid dynamics (CFD) combustion analysis to guide the development of a viable full-load range combustion strategy using a higher reactivity gasoline that has a research octane number (RON) of 70. RON70 was selected as it has the potential to offer a good balance between low load and high load GCI operation.
2017-03-28
Technical Paper
2017-01-0979
Changpu Zhao, Yayong Zhu, Yaohui Wang, Sirui Huang
Although diesel engines have higher output torque, lower fuel consumption, and lower HC pollutant emissions, larger amounts of NOx and PM are emitted, compared with equivalent gasoline engines. The diesel particulate filters (DPF) have proved one of the most promising aftertreatment technologies due to the more stringent particulate matters (PM) regulations. In this study, the computational fluid dynamics (CFD) model of DPF was built by utilizing AVL-FIRE software code. The main objective of this paper was to investigate the pressure drop and soot regeneration characteristics of hexagonal and conventional square cell DPFs with various inlet mass flow rates, inlet temperatures, cell densities, soot loads and ash loads. Different cell geometry shapes of DPF were evaluated under various ash distribution types.
2017-03-28
Technical Paper
2017-01-1016
Charles Schenk, Paul Dekraker
For the upcoming Midterm Evaluation of EPA’s 2017-2025 Light-Duty Vehicle greenhouse gas emissions regulation, EPA has been benchmarking engines and transmissions to generate inputs for use in its technology assessment. As part of the technology assessment, cooled external exhaust gas recirculation (cEGR) and cylinder deactivation (CDA) were evaluated on an engine capable of running the Atkinson cycle. The base engine was a production 2.0L four cylinder engine with 75 degrees of intake phase authority and a 14:1 geometric compression ratio. An open ECU and cEGR hardware were installed on the engine so that the technology effectiveness could be evaluated. Once a steady state calibration was complete, two-cycle fuel economy estimates were made using fuel weighted modes and ALPHA (EPA’s full vehicle simulation model). Additionally, two cylinders were deactivated to determine what two-cycle fuel economy benefits could be achieved.
2017-03-28
Technical Paper
2017-01-0959
Changpu Zhao, Yayong Zhu, Sirui Huang
Although diesel engines offer higher thermal efficiency and lower fuel consumption, larger amounts of Particulate Matters (PM) are emitted in comparison with gasoline engines. The Diesel Particulate Filters (DPF) have proved one of the most promising technologies due to the “particle number” emissions regulations. In this study, the Computational Fluid Dynamics (CFD) multi-channel model of DPF was built properly by utilizing AVL-Fire software code to evaluate the pressure drop and soot accumulation characteristics of DPF. The main objective of this paper was to investigate the effects of soot (capacity and deposit forms) and ash (capacity and distribution factors) interaction on DPF pressure drop and soot accumulation, as well as the effects of DPF boundary conditions (inlet mass flow rate and inlet temperature) on pressure drop.
2017-03-28
Technical Paper
2017-01-1275
David Hobbs, Charles Ossenkop, Andy Latham
Global sales of electric and hybrid vehicles continue to grow as emission legislation forces vehicle manufacturers to build cleaner vehicles, with some 8 million already in service. Hybrid and Electric vehicles contain some of the most complex systems ever used in the automotive field, sophisticated and unique electric hybrid systems are added to modern motor vehicles which re already quite complex. As these vehicles reach the end of their lives they will be processed by the global vehicle recycling industry and the high voltage components will be reused, recycled or re-purposed. This paper explores safe working practices for businesses involved in a global marketplace who are completing battery disabling, removal, disassembly, storage and shipping; includes the various technologies and safe working practices along with some of the legal restrictions on dismantling, storage and shipping of high voltage batteries around the world.
2017-03-28
Technical Paper
2017-01-0683
Michael Fischer, Philipp Kreutziger, Yong Sun, Adam Kotrba
External EGR has been used on diesel engines for decades. It has also been used on gasoline engine in the past. It was recently reintroduced on gasoline engines to improve fuel economy at mid and high engine load conditions, where EGR can reduce fuel enrichment. Fuel enrichment causes fuel penalty and high soot particulate numbers, which will be limited by Europe RDE legislation from 2017 onwards. Under stoichiometric conditions, gasoline engines can be operated at high EGR rate (> 20%), but compared to diesel engines, it needs extreme cooling (~50°C) to gain the maximum fuel economy improvement. However, external EGR and its problems at low temperatures (fouling, corrosion & condensation) are well known . To avoid this, Tenneco introduced a coated Gasoline Particulate Filter in the EGR loop to clean the EGR gas by removing particulates, HC, NOx and CO. Only CO2, N2 and H2O will remain in the cleaned EGR.
2017-03-28
Technical Paper
2017-01-0915
Haomiao Zhang, Yuanzhou Xi, Changsheng Su, Z. Gerald Liu
Diesel exhaust fluid, DEF, (32.5 wt.% urea aqueous solution) is widely used as the NH3 source for selective catalytic reduction (SCR) of NOx in diesel aftertreatment systems. The transformation of sprayed liquid phase DEF droplets to gas phase NH3 is a complex physical and chemical process. Briefly, it experiences water vaporization, urea thermolysis/decomposition and hydrolysis. Depending on the DEF doser, decomposition reaction tube (DRT) design and operating conditions, incomplete decomposition of injected urea could lead to solid urea deposit formation in the diesel aftertreatment system. The formed deposits could lead to engine back pressure increase and DeNOx performance deterioration etc. The formed urea deposits could be further transformed to chemically more stable substances upon exposure to hot exhaust gas, therefore it is critical to understand this transformation process.
2017-03-28
Technical Paper
2017-01-0999
Yuanzhou Xi, Nathan Ottinger, Z. Gerald Liu
Natural gas powered vehicles are attractive in certain applications due to their lower emissions in general than conventional diesel engines and the low cost of natural gas. For stoichiometric natural gas engines, the aftertreatment system typically consists only of a three-way catalyst (TWC). However, increasingly stringent NOx and methane regulations challenge current TWC technologies. In this work, a catalyst reactor system with variable lean/rich switching capability was developed for evaluating TWCs for stoichiometric natural gas engines. The effect of varying frequency and duty-cycle during lean/rich gas switching experiments was measured with a hot-wire anemometer (HWA) due to its high sensitivity to gas thermal properties. A theoretical reactor gas dispersion model was then developed and validated with the HWA measurements. The model is capable of predicting the actual lean/rich gas exposure to the TWC under different testing conditions.
2017-03-28
Technical Paper
2017-01-0967
Xin Liu, Jeong Kim, Timothy Chanko, Christine Lambert, James Pakko
With an emerging need for gasoline particulate filters (GPFs) to lower particle emissions, studies are being conducted to optimize GPF designs in order to balance filtration efficiency, backpressure penalty, filter size, cost and other factors. Metallic filters with a fibrous structure could offer additional designs to the current GPF portfolio, which is currently dominated by ceramic wall-flow filters. However, knowledge on their performance as GPFs is still limited. In this study, modeling on backpressure and filtration efficiency of fibrous media was carried out to determine the design criteria (filtration area, filter thickness and size) for different target efficiencies and backpressures at given gas flow conditions. Filter media with different fiber sizes (8 - 17 μm) and porosities (80% and 90%) were evaluated using modeling to determine the influence of fiber size and porosity. A comparison of fibrous filters with their ceramic counterparts is also discussed.
2017-03-28
Technical Paper
2017-01-0766
Gary D. Neely, Radu Florea, Jason Miwa, Zainal Abidin
Although low diesel fuel prices have reduced the appeal of natural gas (NG) engines recently, the CO2 advantage and low NOX and PM potential of NG makes it well-suited for meeting future greenhouse gas (GHG) and potential lower NOX regulations for on-road medium and heavy-duty engines. However, traditional NG fueling strategies and/or poor air/fuel ratio control can result in significant levels of tailpipe methane (CH4) emissions which offset the CO2 advantage due to the high global warming potential of CH4. To address this issue, the unique co-direct injection capability of the Westport HPDI fuel system was leveraged to obtain a partially-premixed fuel charge by injecting NG during the compression stroke followed by diesel injection for ignition timing control. This combustion strategy, referred to as DI2, was shown to improve the brake thermal and combustion efficiencies over equivalent fumigated dual-fuel combustion modes in a previous publication.
2017-03-28
Technical Paper
2017-01-0983
Masaaki Ito, Frank Katsube, Yasuhiko Hamada, Hiroaki Ishikawa, Tsuyoshi Asako
Alternative Particle Number Emission Test Method Establishment Particle Number (PN) regulation was firstly introduced for European light-duty diesel vehicles in 2011. Since then, PN regulation has been and is being expanded to heavy-duty diesel vehicles and non-road diesel machineries. PN regulation will also be expanded to China and India around 2020 or later. Diesel Particulate Filter (DPF) and Gasoline Particulate Filter (GPF) are mandatory for the above-mentioned PN regulations. These filter technologies are to be continued to evolve for the near future tighter PN regulation. However, PN emission test for filter technology development is currently and mainly carried out with chassis dynamometer, which is costly and time-consuming. This paper describes a simplified and relatively quicker alternative PN emission test method for accelerating filter technology development compared to the current test method.
2017-03-28
Technical Paper
2017-01-0922
Akito Takayama, Takahiro Kurokawa, Hiroki Nakayama, Takuya Katoh, Makoto Nagata
New Pd-Rh type CC-TWC (three way catalysts in CC (close-coupled) position) has been developed to improve low-temperature gas activity. In this study Pd top and Rh bottom layered TWC was used, and Ba and La were tested as an additive to Pd, respectively. Alumina was used for Pd support and La or Ba was co-supported to Pd. The catalysts were aged at 950C for 200hrs and CO, HC and NOx performance were evaluated. As a result, Pd-La catalyst showed higher gas performance than Pd-Ba catalyst. The reason and mechanism of this phenomenon were investigated by three points. First one is Pd activation by the additives, second one is Pd particle size by increasing thermal durability of alumina support, and third one is specific NOx adsorption and desorption by the additives. Pd activity seemed to be increased by La addition but details of activation energy analysis and characterization of Pd by XPS, etc. are under investigation.
2017-03-28
Technical Paper
2017-01-0763
Ehsan Faghani, Pooyan Kheirkhah, Christopher W.J. Mabson, Gordon McTaggart-Cowan, Patrick Kirchen, Steve Rogak
High-pressure direct-injection (HPDI) in heavy duty engines allows a natural gas (NG) engine to maintain diesel-like performance while deriving most of its power from NG. A small diesel pilot injection (5-10% of the fuel energy) is used to ignite the direct injected gas jet. The NG burns in a predominantly mixing-controlled combustion mode which can produce particulate matter (PM). Here we study the effect of injection strategies on emissions from a HPDI engine in two parts. Part-I investigated the effect of late post injection (LPI); the current paper (Part-II) reports on the effects of slightly premixed combustion (SPC) on emission and engine performance. In SPC operation, the diesel injection is delayed, allowing more premixing of the natural gas prior to ignition. PM reductions and tradeoffs involved with gas slightly premixed combustion was investigated in a single-cylinder version of a 6-cylinder, 15 liter HPDI engine.
2017-03-28
Technical Paper
2017-01-1000
Jong Lee, Yu Zhang, Tom Tzanetakis, Michael Traver, Melanie Moses-DeBusk, John Storey, William Partridge, Michael Lance
With higher volatility and longer ignition delay characteristics than typical diesel fuel, low cetane naphtha fuel has been shown to promote partially premixed combustion and produce lower soot for improved fuel economy. In this study, emission performance of low cetane, low octane naphtha (CN 35, RON 60) as a drop-in fuel was examined on a MY13 Cummins ISX15 6-cylinder heavy-duty on-highway truck engine and aftertreatment system. Using the production hardware and development calibrations, both the engine-out and tailpipe emissions of naphtha and ultra-low sulfur diesel (ULSD) fuels were examined during the EPA’s heavy-duty emission testing cycles. Without any modification to the calibrations, the tailpipe emissions were comparable when using naphtha or ULSD on the heavy duty Federal Test Procedure (FTP) and ramped modal cycle (RMC) test cycles.
2017-03-28
Technical Paper
2017-01-0163
Gursaran D. Mathur
In southern states (e.g., Arizona) typically people drive their vehicles in summer by running vehicle’s air conditioning systems in recirculation modes only. Carbon dioxide exhaled by occupants remains within the cabin during operation in recirculation mode. The concentration of carbon dioxide starts increasing in the cabin. The CO2 that is inhaled by the occupants goes into their blood stream that negatively affects occupant’s health. ASHRAE Standard 62 specifies the safe levels of carbon dioxide in conditioned space for humans. The CO2 concentration limit per ASHRAE is 700 ppm over the ambient conditions on a continuous basis. Current global average ambient concentration level of CO2 as of March 2015 (NOAA, 2016) is approximately 401 ppm. Hence, if the CO2 concentration exceeds approximately 1100 ppm inside of a home or a vehicle cabin, then we must introduce outside air into the home or vehicle cabin to reduce the CO2 concentration.
2017-03-28
Technical Paper
2017-01-0700
Valentin Soloiu, Aliyah Knowles, Jose Moncada, Emerald Simons, Martin Muinos, Thomas Beyerl
The Cottonseed biodiesel combustion, sound and vibrations have been evaluated in a medium duty single cylinder DI engine (1.1L/cyl) by comparison with s ULSD#2 reference values. The engine was supercharged and had 20% EGR and all tests were conducted at 1400 rpm and at 4 bar BMEP load. Cylinder pressure was determined using a Kistler piezoelectric transducer. Combustion pressures peaked at 76 bar for both fuels. Ignition delay for CS100 decreased by 0.16 ms when compared to the ULSD#2 baseline. This would lead to a 23% lower peak heat release rate when operating CS100. The pressure rise rate for CS100 was 20% lower than ULSD#2, which related to the reduced ringing intensity for the biodiesel. The sound and vibrations were measured using a B&K condenser type multi-field microphone, and a tri-axial, piezoelectric accelerometer. All noise & vibration signals were analyzed with CPB and FFT Analysis, and Crank Angle Domain Analysis with B&K Pulse Platform software.
2017-03-28
Technical Paper
2017-01-0169
Ward J. Atkinson, William Raymond Hill, Gursaran D. Mathur
The EPA has issued regulations in the Final Rulemaking for 2017-2025 Light-Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards (420r12901-3). This document provides credits against the fuel economy regulations for various Air Conditioning technologies. One of these credits is associated with increased use of re-circulation air mode, when the Ambient is over 24°C (75°F.). The authors want to communicate the experiences in their careers that highlighted issues with air quality in the interior of the vehicle cabin. Cabin contamination sources may result in safety and health issues for both younger and older drivers. Alertness concerns may hinder their ability to operate a vehicle safely.
2017-03-28
Technical Paper
2017-01-0914
Mengchao Zhang
Since diesel engines have higher thermal efficiency, larger power and better fuel economy than gasoline engines, diesel engines are widely used in vehicle, construction machinery and agricultural machinery. However, they emit more hazardous pollutants than gasoline engines, especially particulate emission, which has negative impact on human health and environment quality. In order to meet future increasingly stringent regulations for particulate emission, exhaust gas after-treatment technologies of diesel engines are essential. Particulate emissions from a heavy-duty diesel engine which meets the China national V emission regulation were studied, and the engine was equipped with/without diesel oxidation catalyst (DOC), catalyzed diesel particulate filter (CDPF) and selective catalytic reduction (SCR). The fuel used in this article is ultra low sulfur diesel fuel whose sulfur content is less than 10 ppm.
2017-03-28
Technical Paper
2017-01-0933
Yunhua Zhang, Diming Lou, Piqiang Tan, Zhiyuan Hu, Qian Feng
Biodiesel as a renewable energy is becoming increasingly attractive due to the growing scarcity of conventional fossil fuels. Meanwhile, the development of after-treatment technologies for the diesel engine brings new insight concerning emissions especially the particulate matter pollutants. In order to study the coupling effects of biodiesel blend and CCRT (Catalyzed Continuously Regeneration Trap) on the particulate matter emissions, the particulate matter emissions from an urban bus operated under steady and transient conditions respectively on real road equipped with and without CCRT (the same bus) fuelled with biodiesel blends BD10 (90% pure diesel and 10% biodiesel by volume) and BD0 (100% pure diesel) was tested and analyzed using electrical low pressure impactor (ELPI). Results showed that the particulate number-size distribution of BD10 had two peaks in nuclei mode and accumulation mode respectively except the condition of high speed, which was similar to BD0.
2017-03-28
Technical Paper
2017-01-0991
Sunil Kumar Pathak, Yograj Singh, Vineet sood, Salim Abbasbhai Channiwala
Presently, regulatory emission and fuel consumption values for new car are determined by a type-approval process. Several studies have shown that the type-approval data is not representative for real-world usage. The working group designated as Real Driving Emissions – Light Duty Vehicle (RDE-LDV) assessing the potential of two candidate testing procedures: Emission testing with random driving cycles in the laboratory, and on-road emissions testing with Portable Emissions Measuring Systems (PEMS) as real driving test procedure. The recent reports concluded that both PEMS and random cycle testing are technically feasible. The random cycle testing is more effective than emissions testing with the NEDC, but potentially cover a smaller range of driving conditions but it allows use of established, accurate analytical equipment, and enables the repetition and reproduction of individual emission tests under defined conditions.
2017-03-28
Technical Paper
2017-01-1217
Jiangong Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
An alternating current (AC) heating method for a NMC lithium-ion battery with 8Ah capacity is proposed in the paper. The effects of excitation frequency, current amplitudes, and voltage limit condition on the temperature evolution are investigated experimentally. Current amplitudes are set to 24A(3C), 40(5C), and 64A(8C), and excitation frequencies are set to 300Hz, 100Hz, 30Hz, 10Hz, 5Hz, and 1Hz respectively. The voltage limitations are necessary to protect cells from overcharge. Therefore the voltage limit condition (4.2V/2.75V, 4.3V/2.65V, and 4.4V/2.55V) are also considered in depth to verify the feasibility of the AC heating method. The temperature rises prominently as the current increases, and the decrement of frequencies also lead to the obvious growth of battery temperature. The battery obtains the maximum temperature rise at 64A and 1Hz, which takes 1800s to heat up the battery from -25oC to 18oC.
Viewing 1 to 30 of 21876