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Viewing 181 to 210 of 22397
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
Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco, Francesco Catapano
Abstract The use of methane as supplement to liquid fuel is one of the solution proposed for the reduction of the internal combustion engine pollutant emissions. Its intrinsic properties as the high knocking resistance and the low carbon content makes methane the most promising clean fuel. The dual fuel combustion mode allows improving the methane combustion acting mainly on the methane slow burning velocity and allowing lean burn combustion mode. An experimental investigation was carried out to study the methane-gasoline dual fuel combustion. Methane was injected in combustion chamber (DI fuel) while gasoline was injected in the intake manifold (PFI fuel). The measurements were carried out in an optically accessible small single-cylinder four-stroke engine. It was equipped with the cylinder head of a commercial 250 cc motorcycles engine representative of the most popular two-wheel vehicles in Europe. UV-visible spectroscopy measurements were performed to analyze the combustion process with high spatial and temporal resolution.
Technical Paper
2014-04-01
Valentin Soloiu, Alejandro Rivero-Castillo, Martin Muinos, Marvin Duggan, Spencer Harp, Wallace Peavy, Sven Wolter, Brian Vlcek
Abstract This study presents the combustion and emissions characteristics of Reactivity Controlled Combustion Ignition (RCCI) produced by early port fuel injection (PFI) of low reactivity n-butanol (normal butanol) coupled with in cylinder direct injection (DI) of cottonseed biodiesel in a diesel engine. The combustion and emissions characteristics were investigated at 5.5 bars IMEP at 1400 RPM. The baseline was taken from the combustion and emissions of ULSD #2 which had an ignition delay of 13° CAD or 1.5ms. The PFI of n-butanol and DI of cottonseed biodiesel strategy showed a shorter ignition delay of 12° CAD or 1.45ms, because of the higher CN of biodiesel. The combustion proceeded first by the ignition of the pilot (cottonseed biodiesel) BTDC that produced a premixed combustion phase, followed by the ignition of n-butanol that produced a second spike in heat release at 2° CAD ATDC. The addition of n-butanol into the cycle reduced the compression and peak temperature by 100K and resulted in 35% NOx and 90% soot reduction.
Technical Paper
2014-04-01
Hassan Ali Khairallah, Umit Koylu
Abstract During the past decade, considerable efforts have been made to introduce alternative fuels for use in conventional diesel and gasoline engines. There is significant interest in adding hydrogen to a diesel engine to reduce emissions and improve efficiency. With the rapid increase in computational capabilities, computational fluid dynamics (CFD) codes have become essential tools for the design, control, and optimization of dual fuel engines. In the present study, a reduced chemical kinetics mechanism, consisting of 52 reactions and 29 chemical species for n-heptane fuel combustion, was incorporated with detailed chemical kinetics consisting of 29 reactions for hydrogen including additional nitrogen oxidation. This reaction mechanism was coupled with a 3D CFD model based on AVL FIRE software to investigate the performance and emission characteristics of a diesel engine with low amounts of hydrogen addition. The model was validated by the experimental results and then employed to examine important parameters that have significant effects on the engine performance.
Technical Paper
2014-04-01
Debabrata Barik, Murugan Sivalingam
Abstract The present study was aimed to run the diesel engine only with two renewable fuels in a dual fuel mode. The karanja methyl ester (KME) derived from karanja oil was used as an injected fuel, and the biogas obtained from the anaerobic digestion of pongamia pinnata (Karanja) de-oiled cakes, was used as a secondary fuel in a single cylinder, four stroke, air cooled, direct injection (DI) diesel engine. Four different flow rates of biogas, viz., 0.3 kg/h, 0.6 kg/h, 0.9 kg/h and 1.2 kg/h were inducted along with the air in the suction of the engine. The results of the experiment were compared with those of diesel and KME operations. Biogas inducted at a flow rate of 0.9 kg/h was found to be the best among all the flow rates, in terms of the performance and emission of the engine. The dual fuel operation showed a higher BSEC than that of diesel operation at full load. In dual fuel operation, about 22% of KME replacement was possible with the biogas flow rate of 0.9 kg/h at full load.
Technical Paper
2014-04-01
Michael Andrew Smith, Krishna Kamasamudram, Tamas Szailer, Ashok Kumar, Aleksey Yezerets
Abstract The ammonia slip catalyst (ASC), typically composed of Pt oxidation catalyst overlaid with SCR catalyst, is employed for the mitigation of NH3 slip originating from SCR catalysts. Oxidation and SCR functionalities in an ASC can degrade through two key mechanisms i) irreversible degradation due to thermal aging and ii) reversible degradation caused by sulfur-oxides. The impact of thermal aging is well understood and it mainly degrades the SCR function of the ASC and increases the NH3 conversion to undesired products [1]. This paper describes the impact of sulfur-oxides on critical functions of ASC and on NH3 oxidation activity and selectivity towards N2, NOx and N2O. Furthermore impact of desulfation under selected conditions and its extent of ASC performance recovery is explained.
Technical Paper
2014-04-01
Shubham Sharma, Naveen Kumar, Sambhav Jain, Sidhant Kumar
Abstract The present consumption rates and heavy dependence on fossil fuels pose a humongous threat to the environment. The increased pollution in urban areas is already causing serious sociological, ecological and economic implications. The issue of energy security led governments and researchers to look for alternate means of renewable and environment friendly fuels. Biodiesel has been one of the promising, and economically viable alternatives. The biodiesels are reported to cause reduction in CO, HC and PM emissions. However, NOx emissions are increased in case of biodiesel in CI engine. Therefore, a Urea-SCR over Fe-ZSM5 honeycomb substrate (400cpsi) zeolite catalyst after treatment system is an effective technology to reduce emissions for biodiesel applications. Exhaust gases pass through the catalyst and reactions take place along its surface, consequently converting NOx into nitrogen and H2O. This conversion compliments the functioning of fish oil biodiesel in reducing the overall emissions.
Technical Paper
2014-04-01
Krishna Kamasamudram, Ashok Kumar, Jinyong Luo, Neal Currier, Aleksey Yezerets, Thomas Watkins, Larry Allard
Abstract An operational challenge associated with SCR catalysts is the NH3 slip control, particularly for commercial small pore Cu-zeolite formulations as a consequence of their significant ammonia storage capacity. The desorption of NH3 during increasing temperature transients is one example of this challenge. Ammonia slipping from SCR catalyst typically passes through a platinum based ammonia oxidation catalyst (AMOx), leading to the formation of the undesired byproducts NOx and N2O. We have discovered a distinctive characteristic, an overlapping NH3 desorption and oxidation, in a state-of-the-art Cu-zeolite SCR catalyst that can minimize NH3 slip during temperature transients encountered in real-world operation of a vehicle. In this work we show new insights, gained from NH3 temperature programmed desorption and oxidation experiments, into the Cu-zeolite catalyst functions responsible for the overlap of NH3 desorption and oxidation characteristics and the impact of hydrothermal treatment on these functions.
Technical Paper
2014-04-01
Shun Hong Long, Lianhua Tang, Guodong Yan, Ben Niu, Guanyu Zheng, Fengshuang Wang, Suying Zhang, Jianhua Zhang, Jianzhong Tao
Abstract To satisfy China IV emissions regulations, diesel truck manufacturers are striving to meet increasingly stringent Oxides of Nitrogen (NOx) reduction standards. Heavy duty truck manufacturers demand compact urea SCR NOx abatement designs, which integrate injectors, NOx sensors and necessary components on SCR can in order to save packaging space and system cost. To achieve this goal, aftertreatment systems need to be engineered to achieve high conversion efficiencies, low back pressure, no urea deposit risks and good mechanical durability. Initially, a baseline Euro IV Urea SCR system is evaluated because of concerns on severe deposit formation. Systematic enhancements of the design have been performed to enable it to meet multiple performance targets, including emission reduction efficiency and low urea deposit risks via improved reagent mixing, evaporation, and distribution. Acoustic performance has been improved from the baseline system as well. The optimized system improved ammonia uniformity, eliminated urea deposits, improved NOx conversion efficiency while satisfying existing EU III installation packing space.
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
Stephen Johnson, Peter Croswell, Michael Smith
Abstract “Zoning” a catalytic converter involves placing higher concentrations of platinum group metals (PGM) in the inlet portion of the substrate. This is done to optimize the cost-to-performance tradeoff by increasing the reaction rate at lower temperatures while minimizing PGM usage. A potentially useful application of catalyst zoning is to improve performance using a constant PGM mass. A study was performed to assess what the optimum ratio of front to rear palladium zone length is to achieve the highest performance in vehicle emission testing. Varying the zone ratio from 1:1 to 1:9 shows a clear hydrocarbon performance optimum at a 1:5.66 (15%/85%) split. This performance optimum shows as both a minimum in FTP75 non-methane organic gas (NMOG) emissions as well as a minimum in hydrocarbon, carbon monoxide, and nitrogen oxide light-off temperature. Overall, an improvement of 18%, or 11 mg/mi of combined NMOG+NOx emissions was obtained without using additional PGM. This study shows how the competing forces of active PGM site concentration and available surface area interact in modern three way catalyst design.
Technical Paper
2014-04-01
Seung-Jae Yi, Hyung Kee Kim, Sergio Quelhas, Christopher Giler, Dinh Dang, Sang Beom Kim
Abstract A SULEV proposal was investigated for a Hyundai Elantra 1.8L Nu Engine, combining advanced catalyst technologies with optimized engine management control. A washcoat system using 20% less PGM loading and an optimized EMS calibration were developed to meet the 50% development target of the LEV III SULEV30 standards. This paper highlights revisions made to the new control and catalyst systems which include, 1) improved light-off time and cold-start emissions, 2) optimized cold lambda control, 3) reduced number of fuel cut events, 4) a new catalyst technology to match exhaust gas characteristics, and 5) a Pd-only front catalyst with reduced PGM.
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
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
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
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
Nicholas Gysel, George Karavalakis, Thomas Durbin, Debra Schmitz, Arthur Cho
Abstract The primary objective of this study was to evaluate the impact of three different biodiesel feedstocks on emissions compared to a baseline CARB ULSD with two heavy-duty trucks equipped with and without aftertreatment technologies. The biodiesels included a soybean oil methyl ester (SME), a waste cooking oil methyl ester (WCO), and a methyl ester obtained from animal fat (AFME), blended at a 50% level by volume with the CARB diesel. The vehicles were equipped with a 2010 Cummins ISX-15 engine with a selective catalytic reduction (SCR), diesel oxidation catalyst (DOC) and a diesel particulate filter (DPF) and with a 2002 Cummins ISX-450 engine. Both vehicles were tested over the Urban Dynamometer Driving Schedule (UDDS) on a heavy-duty chassis dynamometer. For this study, nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO2), total hydrocarbons (THC), methane (CH4), non-methane hydrocarbons (NMHC), and particulate matter (PM) were measured. In conjunction with these measurements, unregulated emissions, including ammonia (NH3), carbonyl compounds, and light aromatic hydrocarbons were measured for both vehicles.
Technical Paper
2014-04-01
Harveer Singh Pali, Naveen Kumar, Chinmaya Mishra
Abstract In the present study, ethanol was added in lower proportions to non-edible vegetable oil “Schleichera oleosa” or “Kusum”, to evaluate various performance and emission characteristics of a single cylinder; diesel engine. For engine's trial, four samples were prepared with 5%, 10%, 15% and 20% ethanol in kusum oil (v/v) and the blends were named as E5K95, E10K90, E15K85 and E20K80 respectively. Neat Kusum oil was named as K100. The results indicated that brake thermal efficiency (BTE) was found to increase with increase in volume fraction of ethanol in the kusum oil. E5K95, E10K90, E15K85 and E20K80 test fuels exhibited maximum BTE of 25.4%, 26.4%, 27.4% and 27.7% respectively as compared to 23.6% exhibited by the neat Kusum oil. Similarly, full load brake specific energy consumption (BSEC) decreased from 16.3MJ/kWh in case of neat Kusum oil to 15.1MJ/kWh for E20K80 with an almost linear reduction pattern with increased ethanol composition in the test fuel. Full load carbon monoxide emissions were found to be 0.18% volume for neat Kusum oil which was reduced to 0.1% for E20K80.
Technical Paper
2014-04-01
Romaeo Dallanegra, Rinaldo Caprotti
Abstract The use of Diesel Particulate Filters (DPFs) as a means to meet ever more stringent worldwide Particulate Matter/ Particle Number (PM/ PN) emissions regulations is increasing. Fuel Borne Catalyst (FBC) technology has now been successfully used as an effective system for DPF regeneration in factory and service fill as well as retrofit applications for several years. The use of such a technology dictates that it be stable in long term service and that it remains compatible with new and emerging diesel fuel grades. In order to ensure this, neat additive stability data have been generated in a very severe and highly transient temperature cycle and a large selection of current (Winter 2012) market fuels have been evaluated for stability with this FBC technology. Results indicate that FBC technology remains suitable. The incidence of Internal Diesel Injector Deposits (IDIDs) is increasing, particularly for advanced FIE systems. These deposits generate a variety of field issues that can, in extreme cases, require the fitting of a new set of injectors.
Technical Paper
2014-04-01
Christian Lohfink, Dennis Wiese, Wolfgang Reiser
Abstract Although in the European Union in general no metal containing additives are used, in 2009 a limitation of manganese in gasoline fuel up to 6 mg manganese per liter was introduced in the revised Fuels Quality Directive. In this paper the influences and risks of metal-based additives on the aging of exhaust system components were detected, using the example of the currently allowed manganese content of 6 mg per liter. The legislative endurance test, the Standard Road Cycle (SRC) over the useful life period of 160,000 km conforming to EC Regulation 692/2008 was used. Investigations were carried out with two endurance tests with metal-free-fueled and metal-containing-fueled (reference fuel plus metallic additive) vehicles on a certified chassis dynamometer. The two identical vehicles were both equipped with a typical state of the art downsized DISI engine with Euro 5 application. Euro 5 reference fuel was used as base gasoline. Exhaust emissions were analyzed in fixed intervals over run time in the form of NEDC tests.
Technical Paper
2014-04-01
Francesco Catapano, Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco
Abstract The objective of this paper is the evaluation of the effect of the fuel properties and the comparison of a PFI and GDI injection system on the performances and on particle emission in a Spark Ignition engine. Experimental investigation was carried out in a small single cylinder engine for two wheel vehicles. The engine displacement was 250 cc. It was equipped with a prototype GDI head and also with an injector in the intake manifold. This makes it possible to run the engine both in GDI and PFI configurations. The engine was fuelled with neat gasoline and ethanol, and ethanol/gasoline blends at 10% v/v, 50% v/v and 85% v/v. The engine was equipped of a quartz pressure transducer that was flush-mounted in the region between intake and exhaust valves. Tests were carried out at 3000 rpm and 4000 rpm full load and two different lambda conditions. These engine points were chosen as representative of urban driving conditions. The gaseous emissions and particle concentration were measured at the exhaust by means of conventional instruments.
Technical Paper
2014-04-01
Jim Barker, Colin Snape, David Scurr
Abstract The nature of internal diesel injector deposits (IDID) continues to be of importance to the industry, with field problems such as injector sticking, loss of power, increased emissions and fuel consumption being found. The deposits have their origins in the changes in emission regulations that have seen increasingly severe conditions experienced by fuels because of high temperatures and high pressures of modern common rail systems and the introduction of low sulphur fuels. Furthermore, the effect of these deposits is amplified by the tight engineering tolerances of the moving parts of such systems. The nature and thus understanding of such deposits is necessary to both minimising their formation and the development of effective diesel deposit control additives (DCA). The focused ion beam technique coupled with time of flight secondary -ion mass spectrometry (ToF-SIMS) has the ability to provide information on diesel engine injector deposits as a function of depth for both organic and inorganic constituents.
Technical Paper
2014-04-01
Mohammed Moore Ojapah, Hua Zhao, Yan Zhang
Abstract In recent years, in order to develop more efficient and cleaner gasoline engines, a number of new engine operating strategies have been proposed and many have been studied on different engines but there is a lack of comparison between various operating strategies and alternative fuels at different SI modes. In this research, a single cylinder direct injection gasoline engine equipped with an electro-hydraulic valve train system has been commissioned and used to study and compare different engine operation modes. In this work, the fuel consumption, gaseous and particulate emissions of gasoline and its mixture with ethanol (E15 and E85) were measured and analysed when the engine was operated at the same load but with different load control methods by an intake throttle, reduced intake valve duration, and positive overlap.
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.
Technical Paper
2014-04-01
Zhiqiang Zhang, Fuquan Zhao, Liguang Li, Zhijun Wu, Jun Deng, Zongjie Hu
Abstract Based on high EGR rate, the low temperature combustion (LTC) has been studied widely, of which the application range is more extensive than the homogeneous charge compression ignition (HCCI) and premixed charge compression ignition (PCCI). As the high EGR rate would influence the condition of intake charge, it would also affect the combustion process and the HC emissions, thus the combustion stability of LTC would be lower than tradition diesel combustion. In this study, an ion current detecting technology was employed to explore the ion current at different EGR rates. Meanwhile, the combustion parameters were also investigated, which included the in-cylinder pressure and heat release rate. The CA50 and CAI50 were adopted as the phases of combustion and ion current, which respectively represented the crank angle of mid-point for the integrated heat release and integrated ion current. Then the correlation between CA50 and CAI50 was analysed. Finally, a closed-loop control strategy for LTC was proposed, which was based on the ion current detecting technology.
Technical Paper
2014-04-01
Essam F. Abo-Serie, Mohamed Sherif, Dario Pompei, Adrian Gaylard
Abstract A potentially important, but inadequately studied, source of passengers' exposure to pollutants when a road vehicle is stationary, with an idling engine, results from the ingestion of a vehicle's own exhaust into the passenger compartment through the HVAC intake. We developed and applied a method to determine the fraction of a vehicle's exhaust entering the cabin by this route. Further the influence of three parameters: ambient tail-wind speed, vehicle ground clearance and tail pipe angle, is assessed. The study applies Computational Fluid Dynamic (CFD) simulation to the distribution of exhaust gasses around a vehicle motorized with a 2.2 liter Diesel engine. The simulation employs efficient meshing techniques and realistic loading conditions to develop a general knowledge of the distribution of the gasses in order to inform engineering design. The results show that increasing tail-wind velocity, tail-pipe angle and ground clearance reduces the presence of CO and NO at the HVAC intake.
Technical Paper
2014-04-01
Lennert Sterken, Lennart Lofdahl, Simone Sebben, Tim Walker
Abstract Under a global impulse for less man-made emissions, the automotive manufacturers search for innovative methods to reduce the fuel consumption and hence the CO2-emissions. Aerodynamics has great potential to aid the emission reduction since aerodynamic drag is an important parameter in the overall driving resistance force. As vehicles are considered bluff bodies, the main drag source is pressure drag, caused by the difference between front and rear pressure. Therefore increasing the base pressure is a key parameter to reduce the aerodynamic drag. From previous research on small-scale and full-scale vehicles, rear-end extensions are known to have a positive effect on the base pressure, enhancing pressure recovery and reducing the wake area. This paper investigates the effect of several parameters of these extensions on the forces, on the surface pressures of an SUV in the Volvo Cars Aerodynamic Wind Tunnel and compares them with numerical results. To decrease the dependency of other effects within the engine bay and underbody, the SUV has been investigated in a closed-cooling configuration with upper and lower grille closed and with a smoothened underbody.
Technical Paper
2014-04-01
Karthikeyan N, Anish Gokhale, Narendra Bansode
Abstract The Continuous Variable Transmission (CVT) in scooters is used to transmit the power from the engine to the wheels. The CVT transmission consists of a drive pulley and a driven pulley connected to each other through a belt. The centrifugal clutch is attached to the rear pulley which transmits the power to the wheel. The engagement and disengagement of the clutch generates heat and friction heat is generated between the belt and pulley, thereby requiring continuous external cooling for its safe operation. A centrifugal fan is employed for cooling of the CVT belt. Since the cooling fan takes air from atmosphere, there is always a possibility of dust from the atmosphere entering the system, which might cause wear of pulley and belt, thereby decreasing the performance of the transmission system. The objective of the work is to analyze the dust ingress pattern in to CVT housing. The work aims at simulating the possible conditions for dust entry into the CVT housing for a complete scooter and the study of different design proposals to minimize the dust entry without compromising the cooling requirement of CVT.
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