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Viewing 1 to 30 of 20042
Technical Paper
2014-04-15
Rakesh Kumar Maurya, Avinash Kumar Agarwal
Homogeneous charge compression ignition (HCCI) engines are attracting attention as next-generation internal combustion engines mainly because of very low NOx and PM emission potential and excellent thermal efficiency. Particulate emissions from HCCI engines have been usually considered negligible however recent studies suggest that PM number emissions from HCCI engines cannot be neglected. This study is therefore conducted on a modified four cylinder diesel engine to investigate this aspect of HCCI technology. One cylinder of the engine is modified to operate in HCCI mode for the experiments and port fuel injection technique is used for preparing homogenous charge in this cylinder. Experiments are conducted at 1200 and 2400 rpm engine speeds using gasoline, ethanol, methanol and butanol fuels. A partial flow dilution tunnel was employed to measure the mass of the particulates emitted on a pre-conditioned filter paper. The collected particulate matter (PM) was subjected to chemical analyses in order to assess the amount of Benzene Soluble Organic Fraction (BSOF) and trace metals (marker of toxicity) using Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES).
Technical Paper
2014-04-01
Tingting Zhang, Xiaomin Xie, Zhen Huang
Abstract The aim of this study is to evaluate the land requirement, energy consumption and GHG (greenhouse gases) emissions of microalgal biodiesel (M-BD) and Jatropha curcas seeds (J-BD) based biodiesel from the perspective of life cycle assessment (LCA). Mass and energy balance was used through the whole LCA calculation for each process. Two types of biodiesel (100% biodiesel: BD100, and 20% blends of biodiesel: BD20) were assumed to be combusted in the suitable diesel engine. Displacement method was adopted to measure the co-products credits. The results showed that the land requirement of producing 1 kg biodiesel from microalgae was about 1/31 of that from Jatropha curcas seeds. The well to pump (WTP) stage for microalgal biodiesel had higher fossil energy requirement but lower petroleum energy consumption and GHG emissions compared to Jatropha curcas and conventional diesel (CD). The WTP energy efficiency for J-BD100 and M-BD 100 were 26% and 17.4%, respectively. The feedstock growing stage of microalgae and Jatropha curcas was found to be the most fossil energy-intensive stage.
Technical Paper
2014-04-01
Atsushi Mizutani
Abstract This paper describes the development of high efficiency and compact bumper recycling equipment for facilitating bumper recycling globally. Various equipment to remove paint coat from bumper has been developed since 90s', using mechanical, physical or chemical method. However, it is difficult to promote bumper recycling without realizing cost effective overall system from paint coat removal to pelletizing. Our company jointly developed method of mechanically removing paint coat and has committed to bumper recycling in the form of outsourcing since 2000. In 2010, a dedicated plant for recycling bumpers was launched on the premises of our Oppama Assembly Plant in Japan. In the future, promoting bumper recycling at other overseas assembly plants is necessary as vehicle production will expand globally. Having more compact and cost effective recycling system compared to the one at the Oppama plant is required since the scale of the system including bumper crushing, paint coat removal, and pelletizing has to match processing capacity at these plants rather than equipping large one like Oppama's.
Technical Paper
2014-04-01
Alessandro Libriani
Abstract Synthetic rubber is used in automobiles for various applications. Tires, seals, gaskets, engine mounts, wiring cables and under the hood hoses are just a few examples. Synthetic rubber is a man-made material that uses several components as polymers, resins, carbon black, fillers, vulcanizing agents, reinforcement agents. It is a material that heavily depends on oil for its constituency, therefore it has a large carbon footprint. This study proposes the use of natural filler for automotive seals using synthetic rubber in order to reduce the impact on the environment. Calcium carbonate is the most preponderant choice as material filler because it is abundant in nature and is mined extensively. Calcium carbonate is also present in several structures in nature. Oyster shells have a great amount of it as well as egg shells. Egg shells also constitute an environmental bio-hazard when discarded in a landfill due to the organic inner membrane. The use of discarded egg shells is limited to few applications, mainly pharmaceutical.
Technical Paper
2014-04-01
Tae-il Yoo, Hanhee Park, Gubae Kang, Seongyeop Lim
Abstract Development of eco-friendly vehicles have risen in importance due to fossil fuel depletion and the strengthened globalized emission control regulatory requirements. A lot of automotive companies have already developed and launched various types of eco-friendly vehicles which include hybrid vehicles (HEVs) or electric vehicles (EVs) to reduce fuel consumption. To maximize fuel economy Hyundai-Kia Motor Company has introduced eco-friendly vehicles which have downsized or eliminated vibration damping components such as a torque converter. Comparing with Internal Combustion Engine(ICE) powered vehicles, one issue of the electric motor propulsion system with minimized vibration damping components is NVH (Noise, Vibration and Harshness). The NVH problem is caused by output torque fluctuation of the motor system, resulting in the degradation of ride comfort and drivability. Therefore, accomplishing both fuel economy and good NVH performance has become a significantly challenging task in eco-friendly vehicles.
Technical Paper
2014-04-01
Fernando Ortenzi, Giovanni Pede, Ennio Rossi
Abstract The adoption of composed (hybrid) lead acid battery-supercapacitor (SC) storage systems is able to improve performances (availability, durability, range) of an electric microcar. As a matter of fact, the supercapacitors extend the operation time not only by improving the energy efficiency (thanks to a higher contribution of regenerative braking), but also by reducing the power down caused by voltage drop at higher discharge rates. The integration of battery with supercapacitors requires careful analysis and calculation of the relationship between battery peak power and size of the SC bank, needed to have a balanced composition of the hybrid storage system. For this purpose, the optimization process, summarized here, is based on the combination of a conventional lead-acid battery and a commercial SC, with the vehicle running the ECE15 driving cycle. A Matlab/Simulink model has been developed in order to characterize the benefits of the adoption of such hybrid storage system and experimental tests have been used to calibrate it.
Technical Paper
2014-04-01
Teresa Donateo, Fabio Ingrosso, Daniele Bruno, Domenico Laforgia
Abstract This investigation describes the results of an experimental and numerical research project aimed at comparing mileage and CO2 emissions from two different commercial versions of Daimler AG Smart ForTwo car: conventional (gasoline) and electric (ED). The investigation includes numerical simulations with the AVL CRUISE software package and on-board acquisitions. A data acquisition system has been designed for this purpose and assembled on board of the Smart ED. The system is composed by a GPS antenna with USB interface, two current transducers, a NI-DAQ device and a netbook computer with a LabView-VI. This system provided on-board information about driving cycle and current flows, gathered simultaneously by GPS, transducers and NI-DAQ. The system was also used to evaluate the losses of energy during the recharge of the electric car. The two cars have been tested over a wide range of driving conditions related to different routes, traffic conditions and use of on-board accessories (i.e.
Technical Paper
2014-04-01
Hu Li, Ahmad Khalfan, Gordon Andrews
A SI probe car, defined here as a normal commercial car equipped with GPS, in-vehicle FTIR tailpipe emission measurement and real time fuel consumption measurement systems, and temperature measurements, was used for measuring greenhouse gas emissions including CO2, N2O and CH4 under real world urban driving conditions. The vehicle used was a EURO4 emission compliant SI car. Two real world driving cycles/routes were designed and employed for the tests, which were located in a densely populated area and a busy major road representing a typical urban road network. Eight trips were conducted at morning rush hours, day time non-peak traffic periods and evening off peak time respectively. The aim is to investigate the impacts of traffic conditions such as road congestion, grade and turnings on fuel consumption, engine thermal efficiency and emissions. The time aligned vehicle moving parameters with fuel consumption and emission data enabled the micro-analysis of the correlations between these parameters.
Technical Paper
2014-04-01
Benjamin Reuter, Daniel Gleyzes, Markus Lienkamp
Abstract In this analysis we assess the life cycle greenhouse gas (GHG) emissions of four types of vehicles which might play a role in achieving future emission reductions: vehicles using compressed natural gas (CNG), battery electric vehicles (BEVs), mild hybrid CNG vehicles and range extended BEVs. Our analysis covers the manufacturing processes of these vehicles and their use as a city taxi in Singapore. We also consider upstream emissions from fuel and electricity production. All necessary parameters are derived from an intensive literature review and the model for calculating the life cycle emissions is presented. The influence of data uncertainties is analyzed by parameter variations within different scenarios. The calculation results are found to be quite robust: The BEV and the mild hybrid CNG vehicle similarly show very low GHG emissions within all scenarios whereas the pure CNG vehicle always ranks the worst. In an additional scenario we also assessed the influence of an improved electricity generation with lower emissions in the future.
Technical Paper
2014-04-01
Ivan Arsie, Andrea Cricchio, Cesare Pianese, Matteo De Cesare, Walter Nesci
Abstract In the last years the automotive industry has been involved in the development and implementation of CO2 reducing concepts such as the engines downsizing, stop/start systems as well as more costly full hybrid solutions and, more recently, waste heat recovery technologies. These latter include ThermoElectric Generator (TEG), Rankine cycle and Electric Turbo Compound (ETC) that have been practically implemented on few heavy-duty application but have not been proved yet as effective and affordable solutions for the automotive industry. The paper deals with the analysis of opportunities and challenges of the Electric Turbo Compound for automotive light-duty engines. In the ETC concept the turbine-compressor shaft is connected to an electric machine, which can work either as generator or motor. In the former case the power can satisfy the vehicle electrical demand to drive the auxiliaries or stored in the batteries. In the latter case the electric motor can assist the turbine and speed up the compressor when requested.
Technical Paper
2014-04-01
Haichun Yao, Baigang Sun, Huayu Tian, Qinghe Luo, Hongyang Tang
Abstract NOx are the only harmful emissions of hydrogen internal combustion engine. EGR is one of the effective methods to reduce NOx. The traditional EGR is not suitable for hydrogen internal combustion engine. Therefore, the study of influence of hot EGR on hydrogen internal combustion engine is important. A 2.0L hydrogen internal combustion engine with hot EGR system model is employed to optimize the diameter and position of hot EGR based on a simulation analysis. The result shows that both of the combustion temperature and NOx increase as EGR increases due to the rise of intake temperature for low load condition, for heavy load, with the increase of EGR rate, NOx emissions decreases slightly before the mixture equivalence ratio comes to 1and then dropped significantly after the mixture equivalence ratio greater than 1. Unburned hydrogen in TWC has the effect of reducing NOx after catalysts decrease largely. Hydrogen engine combustion characteristics with hot EGR was analyzed, it suggests that EGR hasn't any benefit on combustion and NOx emission under low load condition; however, a significant amount reduce of NOx can be achieved under a rich condition (equivalence ratio greater than 1) by adjusting the EGR rate for high load condition with sacrificing power output slightly.
Technical Paper
2014-04-01
Arnon Poran, Moris Artoul, Moshe Sheintuch, Leonid Tartakovsky
This paper describes a model for the simulation of the joint operation of internal combustion engine (ICE) with methanol reformer when the ICE is fed by the methanol steam reforming (SRM) products and the energy of the exhaust gases is utilized to sustain endothermic SRM reactions. This approach enables ICE feeding by a gaseous fuel with very favorable properties, thus leading to increase in the overall energy efficiency of the vehicle and emissions reduction. Previous modeling attempts were focused either on the performance of ICE fueled with SRM products or on the reforming process simulation and reactor design. It is clear that the engine performance is affected by the composition of the reforming products and the reforming products are affected by the exhaust gas temperature, composition and flow rate. Due to the tight interrelations between the two main parts of the considered ICE-reformer system, it is desirable to create a single model that simulates joint operation of the ICE and the SRM reactor.
Technical Paper
2014-04-01
Raouf Mobasheri, Seyed Alireza Khabbaz
Abstract Exhaust Gas Recirculation (EGR) is an effective pre-treatment technique, which has been widely used to decrease the amount of the oxides of nitrogen (NOx) emission from diesel engines. However, the use of high EGR rates leads to the reduction in oxygen availability in the burning regions of the combustion chamber which impairs the soot oxidation process. Consequently, higher soot generated by EGR leads to long-term usage problems inside the engines such as higher carbon deposits, lubricating oil degradation and enhanced engine wear. In this study, CFD modeling has been carried out to analyze the effects of high EGR rates in conjunction with optimum multiple injection strategies. A heavy-duty DI Diesel engine has been modeled to study the engine performance and emissions with various EGR rates (from 0% to 40%). The selected operating points have been achieved with the same injection profile including a main and post injection for all considered cases. The results showed the effectiveness of multiple injections at controlling soot emission under high EGR conditions.
Technical Paper
2014-04-01
René Wolf, Peter Eilts
When comparing automotive and large-bore diesel engines, the latter usually show lower specific fuel consumption values, while automotive engines are subject to much stricter emission standards. Within an FVV (Research Association for Combustion Engines) project these differences were identified, quantified and assigned to individual design and operation parameters. The approach was split in three different phases: 1 Comparison of different-sized diesel engines2 Correlation of differences in fuel consumption to design and operating parameters3 Further investigations under automotive boundary conditions The comparison in the first phase was made on the basis of operating data and energy balances as well as the separation of losses based on the thermodynamic analysis. To also determine the quantitative effects of each design and operating parameter, a 1D process calculation model of the passenger car engine was transformed gradually to a large-bore engine in the second phase. The advantage of the large-bore engines results basically from their higher combustion air ratio, shorter combustion duration, lower wall heat losses and high positive gas exchange work due to a high turbocharger efficiency.
Technical Paper
2014-04-01
Gangfeng Tan, Ming Chen, Haobo Xu, Bing Luo, Jiameng Wang
Abstract Vacuum cleaning vehicle is the necessary equipment for the Municipal Sanitation Department to keep the road surface clean and the dust subsidence system is the heart unit for the proper function of the cleaning vehicle. The reasonable design of this system could increase the load capacity of the vehicle and be convenient for the garbage collecting and dumping. Meanwhile, the engine power could be relatively reduced and the influence on the environment duo to the dusty air in the outlet could be also effectively improved. In the study, the gravity dedusting principle is used firstly for structure design to reduce the flow rate of dust particles inside the lower part of the dust subsidence system. The ruleless collision loss among dust particles is reduced and thereby the fan power is saved. By means of a reasonable separated chamber design and the use of inertia baffle, the sort management for dust particles is developed and the work stress of the export filter is released observably.
Technical Paper
2014-04-01
Xin Wang, Yunshan Ge
Abstract Compressed natural gas (CNG) is widely used as an alternative option in spark ignition engines because of its better fuel economy and in part cleaner emissions. To cope with the haze weather in Beijing, about 2000 gasoline/CNG dual-fuel taxis are servicing on-road. According to the government's plan, the volume of alternative fuel and pure electric vehicle will be further increased in the future. Thus, it is necessary to conduct an evaluation on the effectiveness of alternative fuel on curbing vehicular emissions. This research examined the regulated emissions and particulate matter of gasoline/CNG dual-fuel taxi over New European Driving Cycle (NEDC). Emission tests in gasoline- and CNG-fuelled, cold- and warm-start modes were done for all five taxies. Test vehicles, Hyundai Elantra, are powered by 1.6L spark-ignited engines incorporated with 5-gear manual gearboxes. The taxis were registered in May and June, 2013, and their millage was within 3500 and 10000 km on odometer when the emission tests were performed.
Technical Paper
2014-04-01
Navin Kumar, Abyarth Behera, Dulari Hansdah, Murugan Sivalingam
Abstract Madhuca indica flower is a forest residue used for preparation of food and liquor in tribal areas of India. In this present investigation, bioethanol produced from madhuca indica flower by the fermentation process is proposed as an alternative fuel for diesel engines. As the cetane number of bioethanol is low, an ignition improver is required for better operation. In this study, Diethyl ether (DEE), an ignition improver is fumigated at two different flow rates viz 120 g/h and 240 g/h in the intake manifold along with the air in a single cylinder, four stroke, DI diesel engine developing a power of 4.4 kW at a rated speed of 1500 rpm. The brake thermal efficiency (BTE) is found to be higher by about 10.47 and 2.46% with 120 g/h and 240 g/h flow rate of the DEE respectively, compared to that of diesel at full load. The brake specific nitric oxide (BSNO) emission is found to be lower for both the flow rates, but the brake specific carbon monoxide (BSCO) and brake specific hydrocarbon (BSHC) emission are found to be higher for the flow rate of 240 g/h compared to 120 g/h of DEE and diesel at full load.
Technical Paper
2014-04-01
Robert L. Russell, Kent Johnson, Thomas Durbin, Nicole Davis, James Lents
Abstract Engine manufacturers have explored many routes to reducing the emissions of harmful pollutants and conserving energy resources, including development of after treatment systems to reduce the concentration of pollutants in the engine exhaust, using alternative fuels, and using alternative fuels with after treatment systems. Liquefied petroleum gas (LPG) is one alternative fuel in use and this paper will discuss emission measurements for several LPG vehicles. Regulated emissions were measured for five school buses, one box truck, and two small buses over a cold start Urban Dynamometer Driving Schedule (CS_UDDS), the Urban Dynamometer Driving Schedule (UDDS), and the Central Business District (CBD) cycle. In general, there were no significant differences in the gas phase emissions between the UDDS and the CBD test cycles. For the CS-UDDS cycle the total hydrocarbons and non-methane hydrocarbon emissions are higher than they are from the UDDS cycle. Methane and carbon monoxide emissions are also higher, but the difference isn't as pronounced.
Technical Paper
2014-04-01
Karthik Nithyanandan, Han Wu, Ming Huo, Chia-Fon Lee
Abstract Alcohols, because of their potential to be produced from renewable sources and their characteristics suitable for clean combustion, are considered potential fuels which can be blended with fossil-based gasoline for use in internal combustion engines. As such, n-butanol has received a lot of attention in this regard and has shown to be a possible alternative to pure gasoline. The main issue preventing butanol's use in modern engines is its relatively high cost of production. Acetone-Butanol-Ethanol (ABE) fermentation is one of the major methods to produce bio-butanol. The goal of this study is to investigate the combustion characteristics of the intermediate product in butanol production, namely ABE, and hence evaluate its potential as an alternative fuel. Acetone, n-butanol and ethanol were blended in a 3:6:1 volume ratio and then splash blended with pure ethanol-free gasoline with volumetric ratios of 0%, 20%, 40% to create various fuel blends. These blends were tested in a port-fuel injected spark-ignited (SI) engine and their performance was evaluated through measurements of in-cylinder pressure, and various exhaust emissions.
Technical Paper
2014-04-01
Tao Tang, Dongxiao Cao, Jun Zhang, Yan-guang Zhao, Shi-jin Shuai
Abstract The diesel particulate filter (DPF) is an effective technology for particulate matter (PM) and particle number (PN) reduction. On heavy-duty diesel engines, the passive regeneration by Diesel Oxidation catalysts (DOC) and catalyzed DPFs (CDPF) is widely used for its simplicity and low cost, which is generally combined with the active regeneration of exhaust fuel injection. This study investigated a DOC-CDPF system with exhaust fuel injection upstream of the DOC. The system was integrated with a 7-liter diesel engine whose engine-out PM emission was below the Euro IV level and tested on an engine dynamometer. PM and PN concentrations were measured based on the Particle Measurement Programme (PMP), and the number/size spectrum for particles was obtained by a Differential Mobility Spectrometer (DMS). The filtration efficiency of DPF on PN was higher than 99% in ESC test, while the efficiency on PM was only 58%. During the active regeneration, a certain amount of diesel fuel was injected into the tailpipe and then oxidized in the DOC.
Technical Paper
2014-04-01
Eric Hein, Adam Kotrba, Tobias Inclan, Andrew Bright
Secondary fuel injection is applied to facilitate active soot management of the particulate filter within diesel aftertreatment systems, avoiding concerns with fuel delivery via in-cylinder post-injection. System performance is dependent on the thermo-fluid interactions of the injected fuel with the exhaust stream, with the intent of having more fully vaporized fuel and a well-mixed air-fuel mixture at the inlet of the oxidation catalyst for uniform thermal distribution as it exothermically reacts. Pre-heating the fuel with a diesel vaporizer prior to its delivery into the exhaust enables improved system performance, reducing droplet sizes and mixing demands. A diesel vaporizer is applied within the exhaust of a medium duty truck application, and the response of the catalyst is characterized across a variety of conditions. Cross-sectional measurements at the catalyst and filter outlet are described, including gas velocity, temperature, and HC concentration, and the effect of poor fuel vaporization is demonstrated.
Technical Paper
2014-04-01
Da Yu Wang, David M. Racine, Harry Husted, Sheng Yao
Abstract NOx aftertreatment is an essential subsystem to enable diesel and lean gasoline engines to meet emissions regulations. A selective catalytic reduction (SCR) system, which uses urea to create ammonia (NH3) for NOx reduction, is one popular form of NOx aftertreatment system. These urea based NOx aftertreatment systems can benefit from closed-loop control when appropriate NH3, NOx, or NO2 exhaust gas sensors are available. For example, knowing exhaust NO2 emissions after a diesel oxidation catalyst can help the urea dosing strategy to maximize the efficiency of a urea SCR system. Such sensing capability, combined with ammonia sensing, can provide enhanced closed-loop control of the SCR system as well as information for on-board diagnosis. This paper covers Delphi's progress in developing an exhaust NO2 sensor. Sensor data from a synthetic gas bench and from engine testing is presented for four NO2 sensors, along with investigations into the sensor's sensitivity to a variety of relevant factors such as oxygen concentration, humidity, and operating temperature.
Technical Paper
2014-04-01
Achombili Asango, Antonino La Rocca, Paul Shayler
Abstract The influence of size and concentration of carbon nanoparticle on the viscosity of an SAE 5W-30 lubricant oil has been investigated experimentally. Data were collected for oil samples drawn from sump of light duty automotive diesel engines. The average size of soot particles in the used oil samples was in the range of 180-320nm with concentrations ranging from 0 to 2 percentage by weight (wt. %.). A Brookfield DV-II Pro rotary viscometer was used to measure dynamic viscosity at low shear rates and temperatures of 40°C and 90°C. Nanoparticle concentration and particle size distribution were evaluated using Thermo-Gravimetric Analysis (TGA) and Dynamic Light Scattering (DLS) respectively. The viscosity of suspensions of graphite powder in lubricant oil was also investigated for concentrations ranging from 0 to 2 wt. %. The results show that dynamic viscosity increases with increasing soot content and decreasing temperature. Particle size effects are more significant for high soot content.
Technical Paper
2014-04-01
Peter Fussey, David Limebeer
Setting up engines to meet emissions limits often involves extensive steady-state calibration activities combined with ad-hoc strategies to compensate for transient operation. As engines become more complex and acceptable emissions levels ever lower, this task is becoming increasingly time consuming and expensive. The inclusion of models in the engine control units offers a way to reduce some of this calibration effort. Model-based control is an active area of research with advanced approaches now being proposed. One example is the use of real-time models to regulate the burn angle during transient manœuvres. This paper describes the application of a control-orientated combustion model to control directly emissions during transients. The model is used to optimize and constrain the NOx emissions directly, rather than controlling an inferred variable such as the burn angle. This has the benefit that calibration engineers will be able to set the emissions trade-off directly.
Technical Paper
2014-04-01
Matteo De Cesare, Federico Stola, Cosimo Senni, Alfredo Di Monte, Stefano Sgatti
Abstract The Selective Catalytic Reduction (SCR) system, installed on the exhaust line, is currently widely used on Diesel heavy-duty trucks and it is considered a promising technique for Euro 6 compliancy for light and medium duty trucks and bigger passenger cars. Moreover, new more stringent emission regulations and homologation cycles are being proposed for Euro 6c stage and they are scheduled to be applied by the end of 2017. In this context, the interest for SCR technology and its application on light-duty trucks is growing, with a special focus on its potential benefit in term of fuel consumption reduction, thanks to combustion optimization. Nevertheless, the need to warm up the exhaust gas line, to meet the required NOx conversion efficiency, remains an issue for such kind of applications. In this work, the activity performed on different Euro 5-compliant light-duty vehicles, equipped with SCR, to fulfill Euro 6 emission level with fuel saving respect to current production level, is described.
Technical Paper
2014-04-01
Nassim Khaled, Michael Cunningham, Jaroslav Pekar, Adrian Fuxman, Ondrej Santin
Abstract In this paper we consider the issues facing the design of a practical multivariable controller for a diesel engine with dual exhaust gas recirculation (EGR) loops. This engine architecture requires the control of two EGR valves (high pressure and low pressure), an exhaust throttle (ET) and a variable geometry turbocharger (VGT). A systematic approach suitable for production-intent air handling control using Model Predictive Control (MPC) for diesel engines is proposed. Furthermore, the tuning process of the proposed design is outlined. Experimental results for the performance of the proposed design are implemented on a 2.8L light duty diesel engine. Transient data over an LA-4 cycle for the closed loop performance of the controller are included to prove the effectiveness of the proposed design process. The MPC implementation process took a total of 10 days from the start of the data collection to build a calibrated engine model all the way through the calibration of the controller over the transient drive cycle.
Technical Paper
2014-04-01
Kevin Cedrone, Wai K. Cheng
The engine and its exhaust flow behaviors are investigated in a turbo-charged gasoline direct injection engine under simulated cold-fast-idle condition. The metrics of interest are the exhaust sensible and chemical enthalpy flows, and the exhaust temperature, all of which affect catalyst light off time. The exhaust sensible enthalpy flow is mainly a function of combustion phasing; the exhaust chemical enthalpy flow is mainly a function of equivalence ratio. High sensible and chemical enthalpy flow with acceptable engine stability could be obtained with retarded combustion and enrichment. When split injection is employed with one early and one later and smaller fuel pulse, combustion retards with early secondary injection in the compression stroke but advances with late secondary injection. Comparing gasoline to E85, the latter produces a lower exhaust temperature because of charge cooling effect and because of a faster combustion.
Technical Paper
2014-04-01
Justin E. Ketterer, Wai K. Cheng
Abstract Particulate emissions from a production gasoline direct injection spark ignition engine were studied under a typical cold-fast-idle condition (1200 rpm, 2 bar NIMEP). The particle number (PN) density in the 22 to 365 nm range was measured as a function of the injection timing with single pulse injection and with split injection. Very low PN emissions were observed when injection took place in the mid intake stroke because of the fast fuel evaporation and mixing processes which were facilitated by the high turbulent kinetic energy created by the intake charge motion. Under these conditions, substantial liquid fuel film formation on the combustion chamber surfaces was avoided. PN emissions increased when injection took place in the compression stroke, and increased substantially when the fuel spray hit the piston. A conceptual model was established for the particulate matter (PM) formation process in which PM is formed by pyrolysis after the normal premixed flame passage in fuel rich plumes originating from liquid films on the cylinder walls.
Technical Paper
2014-04-01
Xi Luo, Xin Yu, Kan Zha, Marcis Jansons, Valentin Soloiu
Emissions of Unburned Hydrocarbons (UHC) from diesel engines are a particular concern during the starting process, when after-treatment devices are typically below optimal operating temperatures. Drivability in the subsequent warm-up phase is also impaired by large cyclic fluctuations in mean effective pressure (MEP). This paper discusses in-cylinder wall temperature influence on unburned hydrocarbon emissions and combustion stability during the starting and warm-up process in an optical engine. A laser-induced phosphorescence technique is used for quantitative measurements of in-cylinder wall temperatures just prior to start of injection (SOI), which are correlated to engine out UHC emission mole fractions and combustion phasing during starting sequences over a range of charge densities, at a fixed fueling rate. Squish zone cylinder wall temperature shows significant influence on engine out UHC emissions during the warm-up process. Higher surface temperatures correlate with lower levels of engine-out UHC.
Technical Paper
2014-04-01
Dai Liu, Hongming Xu, Ramadhas Arumugam Sakunthalai
Abstract Biodiesel is an oxygenated alternative fuel made from vegetable oils and animal fats via transesterification and the feedstock of biodiesel is diverse and varies between the local agriculture and market scenarios. Use of various feedstock for biodiesel production result in variations in the fuel properties of biodiesel. In this study, biodiesels produced from a variety of real world feedstock was examined to assess the performance and emissions in a light-duty engine. The objective was to understand the impact of biodiesel properties on engine performances and emissions. A group of six biodiesels produced from the most common feedstock blended with zero-sulphur diesel in 10%, 30% and 60% by volume are selected for the study. All the biodiesel blends were tested on a light-duty, twin-turbocharged common rail V6 engine. Their gaseous emissions (NOx, THC, CO and CO2) and smoke number were measured for the study. The emphasis of the investigation is the correlations of the fuel properties such as cetane number, fuel density, GHV (gross heat value) of combustion and oxygen content with the emissions of smoke, THC and NOx.
Viewing 1 to 30 of 20042