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Viewing 1 to 30 of 3982
2017-10-13
Technical Paper
2017-01-5012
Harveer Singh Pali, Shashi Prakash Dwivedi
In the present work, A356/SiC metal matrix composite with different weight percent of SiC particles were fabricated by two different techniques such as mechanical stir-casting and electromagnetic stir casting. The wear and frictional properties of the metal matrix composites were studied by performing dry sliding wear test using a pin-on-disc wear tester for both electromagnetic stir casting samples and mechanical stir casting samples. The wear rate increases with the addition of normal force, while decreases by increasing the percentage of reinforcement. Frictional coefficient increases by increasing the normal force and percentage of reinforcement. Increasing percentage of reinforcement and using electromagnetic stir casting process obtained the higher frictional coefficient and lower wear rate.
2017-10-13
Technical Paper
2017-01-5014
Maurilio Pereira Gomes, Igor Santos, Camila Couto, Cristiano Mucsi, Jesualdo Luiz Rossi, Marco Colosio
This work consists of evaluating the influence of heat treatment of sintered valve seat insert (VSI) manufactured with three different high-speed steels: AISI M3:2, AISI M2 and AISI D2. The high-speed powders were mixed with iron powders and additives such as manganese sulphide, zinc stearate, graphite and carbides. All the used powders had the particle size distribution and morphological aspects analyzed. The heat treatment of the VSI’s consisted of air quenching followed by double tempering in seven different equidistant temperatures (from 100 ºC until 700 ºC). A data acquisition system using thermocouple type K was used to determine the quenching process and mainly the cooling ratio. The physical properties were carried out through the measurement of the VSI’s bulk density and hardness. The metallurgical evaluation consisted of etching the VSI’s and then analyzing it with optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).
2017-10-08
Technical Paper
2017-01-2347
Kazushi Tamura, Kenji Sunahara, Motoharu Ishikawa, Masashi Mizukami, Kazue Kurihara
Modern lubricants such as fuel economy engine oils control friction through tribofilms formed by functional additives mixture. Although many cases on synergistic or antagonistic effects of additives on friction have been reported, their mechanisms are poorly understood. Here we found that some of the detergent additives with metallic soap reduced friction synergistically with molybdenum dithiocarbamate (MoDTC), which is a widely-used friction modifier additive that forms slippery tribofilm, while detergents themselves increased friction without MoDTC. These results indicate that detergents enhance friction-induced formation of slippery tribofilms by MoDTC. To reveal this mechanism, using surface force apparatus equipped with a resonance shear measurement system (SFA-RSM), we examined mechanical properties of detergent-containing oils confined at single-asperity contact.
2017-10-08
Journal Article
2017-01-2346
Hong Liu, Jiajia Jin, Hongyu Li, Kazuo Yamamori, Toyoharu Kaneko, Minoru Yamashita, Liping Zhang
According to the Toyota gasoline engine oil requirements, this paper describes that the low viscosity engine oil of 0W-16 has been developed jointly by Sinopec and Toyota,which also conforms to the Toyota specification. As we know, the development of low viscosity gasoline engine oils should not only focus on fuel economy improvement, but shear stability and low speed pre-ignition (LSPI) prevention property should be taken into consideration. The main elements content in the formulation was determined according to the results of Toyota’s previous LSPI research and the initial 0W-16 engine oil had passed Toyota LSPI test. Based on all above, viscosity index improver (VII) with better friction reduction property was selected by the Mini-traction Machine (MTM) and the High-frequency Reciprocating Rig (HFRR) tests.
2017-10-08
Technical Paper
2017-01-2333
Marcos Gutierrez, Andres Castillo, Juan Iniguez, Gorky Reyes
Abstract Aiming for cleaner and more efficient energy from the internal combustion engines makes necessary to ensure the special conditions for exploitation of alternative fuels. The engine vibrations are primarily understood as effects of mechanical failures, but they are also a subject of the fuel combustion effects. These effects depend on the fuel type and its ability to complete the combustion process. The vibrations of a diesel engine were measured and analyzed with a frequency spectrum calculated with fast Fourier transforms. The engine was operated with a fuel blend of 10 % recycled lubricating oil with 90% diesel fuel as well as with neat diesel. It was found that the engine operation with this fuel blend has a lower vibration level in comparison with the use of neat diesel fuel. The goal of this research is to determine the properties of the fuel blend, which provide more stability to the engine by means of vibrations reduction.
2017-10-08
Technical Paper
2017-01-2344
Robert Taylor, Hua Hu, Carl Stow, Tony Davenport, Robert Mainwaring, Scott Rappaport, Sarah Remmert
Abstract It is anticipated that worldwide energy demand will approximately double by 2050, whilst at the same time, CO2 emissions need to be halved. Therefore, there is increasing pressure to improve the efficiency of all machines, with great focus on improving the fuel efficiency of passenger cars. The use of downsized, boosted, gasoline engines, can lead to exceptional fuel economy, and on a well-to-wheels basis, can give similar CO2 emissions to electric vehicles (depending, of course, on how the electricity is generated). In this paper, the development of a low weight concept car is reported. The car is equipped with a three-cylinder 0.66 litre gasoline engine, and has achieved over 100 miles per imperial gallon, in real world driving conditions.
2017-10-08
Technical Paper
2017-01-2349
Sarita Seth, Swamy Maloth, Prashant Kumar, Bhuvenesh Tyagi, Lokesh Kumar, Rajendra Mahapatra, Sarita Garg, Deepak Saxena, R Suresh, SSV Ramakumar
Abstract Automobile OEMs are looking for improving fuel economy[1,2] of their vehicles by reducing weight, rolling resistance and improving engine and transmission efficiency apart from the aerodynamic design. Fuel economy may be improved by using appropriate low viscosity [3] and use of friction reducers (FRs)[4,5] in the engine oils. The concept of high viscosity index [6] is being used for achieving right viscosity at required operating temperatures. In this paper performance properties of High Viscosity Index engine oils have been compared with conventional VI engine oils. Efforts have been made to check the key differentiation in oil properties w.r.t. low temperature fluidity, high temperature high shear viscosity/deposits, friction behavior, oxidation performance in bench tribological /engine/chassis dyno tests which finally lead to oil performance assessment.
2017-10-08
Technical Paper
2017-01-2422
Na Li, Fenlian Huang, Yuhua Bi, Yueqiang Xu, Lizhong Shen, Dewen Jia
Abstract The assembly of con rod bearing and crankpin is a key friction pair which offers an important guarantee for stable operation of diesel engine. Specific to the non-road 2-cylinder diesel engine developed independently and based on the theory of thermoelastohydrodynamic lubrication as well as multi-body dynamics, this paper establishes a multi-body dynamics model for con rod big end bearings of the 2D25 horizontal diesel engine and makes a research on the influence of bearing width, bearing clearance, and oil inlet position and diameter upon lubrication of con rod bearing, taking into consideration that of the surface appearance of bearing bush and the elastic deformation of bearing bush and axle journal upon the same. Research results show that bearing width and bearing clearance are the major factors that influence lubrication characteristics of con rod bearing while oil inlet position and diameter only have a small influence on such characteristics.
2017-10-08
Technical Paper
2017-01-2423
Xiaoming Ye, Yan Fu, Wei Li, Yuze Jiang, Shixin Zhu
Abstract As the key components of internal combustion engine(ICE), the crankshaft main bearings are used to support the crankshaft and connecting rod mechanism whose rotary motion realizes the energy conversion from heat energy to mechanical power in cylinder. The lubrication performances and wear life of crankshaft main bearings directly affect ICE working efficiency and reliability. Therefore, it is very important to study the lubrication performances of crankshaft main bearings. In this paper, a 16V marine diesel engine was studied. Based on the AVL-Designer software platform, a dynamic model of crankshaft and connecting rod mechanism and a hydrodynamic lubrication model of crankshaft main bearing were built. The numerical analyses were carried out on the lubrication performances of crankshaft main bearings under different speed conditions.
2017-10-08
Technical Paper
2017-01-2357
Mark Devlin, Jeffrey Guevremont, Chip Hewette, Marc Ingram, Grant Pollard, William Wyatt
Abstract Different mechanical components in a vehicle can be made from different steel alloys with various surface treatments or coatings. Lubricant technology is needed to prevent wear and control friction on all of these different surfaces. Phosphorus compounds are the key additives that are used to control wear and they do this by forming tribofilms on surfaces. It has been shown that different operating conditions (pressures and sliding conditions) can influence the formation of tribofilms formed by different anti-wear additives. The effect of surface metallurgy and morphology on tribofilm formation is described in this paper. Our results show that additive technology can form proper tribofilms on various surfaces and the right combination of additives can be found for current and future surfaces.
2017-10-08
Technical Paper
2017-01-2353
Bernardo Tormos, Leonardo Ramirez, Guillermo Miró, Tomás Pérez
Abstract One of the most interesting alternatives to reduce friction losses in the internal combustion engines is the use of low viscosity engine oils. Recently, a new engine oil category focused fuel economy, has been released in North America encouraging the use of these oils in the heavy-duty vehicles’ segment. This paper presents the results of a comparative test where the differences in fuel consumption given by the use of these oils are shown. The test included 48 buses of the urban public fleet of the city of Valencia, Spain. The selected vehicles were of four different bus models, three of them fueled with diesel and the other one with compressed natural gas (CNG). Buses’ fuel consumption was calculated on a daily basis from refueling and GPS mileage. After three oil drain intervals (ODI), the buses using low viscosity engine oils presented a noticeable fuel consumption reduction. These results bear out the suitability of these oils to palliate engine inefficiencies.
2017-10-08
Technical Paper
2017-01-2352
Gongde Liu, Li Wang, Runxiang Zhang, Chao Yang, Tengfei Shao
Abstract Fuel economy, Emission regulation and extended oil drain intervals (ODI) are the three key driving forces for engine oil development. More and more attentions have been focused on long ODI diesel engine oil both from the domestic OEMs and oil suppliers, and the ODI was being periodically improved from a normal mileage of about 1×104 kilometers to 6/8/10×104 km or even 12×104 km just within several years on China market. Lots and lots of factors may affect the oil life including oil properties, engine technologies, after-treatment devices and engine working conditions and so on. While from the oil side, the main factors contribute to the oil drain intervals may be the oil nitration and oxidation, soot contamination, base number deterioration and sludge accumulation and etc. There are two strategies to extend the oil longevity applied currently.
2017-10-08
Technical Paper
2017-01-2351
Bernardo Tormos, Guillermo Miró, Leonardo Ramirez, Tomás Pérez
Abstract Low viscosity engine oils are considered a feasible solution for improving fuel economy in internal combustion engines (ICE). So, the aim of this study was to verify experimentally the performance of low viscosity engine oils regarding their degradation process and possible related engine wear, since the use of low viscosity engine oils could imply higher degradation rates and/or unwanted wear performance. Potential higher wear could result in a reduction in life cycle for the ICE, and higher degradation rates would be translated in a reduction of the oil drain period, both of them non-desired effects. In addition, currently limited data are available regarding “real-world” performance of low viscosity engine oils in a real service fleet.
2017-10-08
Technical Paper
2017-01-2350
Chalermwut Wongtaewan, Umaporn Wongjareonpanit, Komkrit Sivara, Ken Hashimoto, Yoichiro Nakamura
Abstract In Thailand, most heavy-duty trucks were equipped with diesel engine, while a small portion was equipped with compressed natural gas (CNG) engine. However, in the past few years the number of CNG fuel trucks in Thailand has increased significantly due to the cheaper cost of CNG. In general, the emphasis of heavy-duty diesel engine oil performance is on piston cleanliness and soot handling properties, while thermal and anti-oxidation properties are most critical for CNG engine oil performance. For truck fleet owners who operate both types of trucks, using the inappropriate oil that is not fit-for-purpose can adversely affect engine performance and reduce engine service lifespan under prolonged usage. A novel CNG/diesel engine oil was developed to meet both JASO DH-2 heavy-duty diesel engine oil performance and CNG engine oil performance. The candidate formulation was proved adequately fit for practical use regarding to thermal and anti-oxidation properties.
2017-10-08
Technical Paper
2017-01-2437
Renjith S, Vinod Kumar Srinivasa, Umesh Venkateshaiah
Abstract The jet lubrication method is extensively used in the constant mesh high performance transmission system operating at range of speeds though it affects mechanical efficiency through spin power loss. The lubrication jet has a key role to maintain the meshing gears at non-fatal thermal equilibrium by effectively dissipating the heat generated to the surrounding. Heat transfer coefficient (HTC) is the indicator of the thermal behavior of the system, which provides great insight of efficient lubrication system that needs to be employed for prescribed type of transmission. In this study, a segment of the transmission unit which constitutes a gear pair is used for the simulation. Parametric study is carried out by considering the critical parameters affecting the thermal performance such as lubrication jet flow rate and rotational motions of the gears with speeds and temperatures.
2017-10-08
Technical Paper
2017-01-2444
Yanzhong Wang, Guanhua Song
Abstract High-speed rotating gears are generally lubricated by spray lubrication. Lubricating oil is driven by high-speed rotating gear, and some lubricating oil will be excited into oil mist, so that the gears are in the gas-liquid mixed environment. In this paper, the computational fluid dynamics model of the spray lubrication cooling process is established based on the gear heat transfer behavior under the spray lubrication condition. The influence of different spray parameters on the liquid-solid two-phase convective heat transfer coefficient is obtained. On this basis, the accurate boundary conditions of gear temperature field calculation are analyzed by studying the heat transfer behavior of high speed gear spray lubrication. The calculation model of gear temperature based on spray lubrication is established, and the temperature field distribution of gear is obtained.
2017-10-08
Technical Paper
2017-01-2358
Michael P Gahagan
Abstract The automotive vehicle market has seen an increase in the number of hybrid electric vehicles (HEVs), and forecasts predict additional growth. In HEVs, the hybrid drivetrain hardware can combine electric motor, clutches, gearbox, electro-hydraulics and the control unit. In HEV hardware the transmission fluid can be designed to be in contact with an integrated electric motor. One transmission type well-suited to such hybridization is the increasingly utilized dual clutch transmission (DCT), where a lubricating fluid is in contact with the complete motor assembly as well as the DCT driveline architecture. This includes its electrical components and therefore raises questions around the suitability of standard transmission fluids in such an application. This in turn drives the need for further understanding of fluid electrical properties in addition to the more usually studied engineering hardware electrical properties.
2017-10-08
Technical Paper
2017-01-2231
Yongquan Chen, Liguang Li, Qing Zhang, Jun Deng, Wei Xie, Erbao Zhang, Sunyu Tong
Low speed pre-ignition (LSPI) may lead to extreme knock (superknock or megaknock) which has a severe influence on engine performance and service life thus limits the development of downsized GDI engine. One reason for LSPI is auto-ignition occurs in the region where the contaminants, such as lubricants or heavy ends of gasoline, are rich. In this paper, 8 groups of lubricants are injected into a hot co-flow by a single-hole nozzle with a diameter of 0.2 mm under 20 MPa injection pressure. The ignition delays and lifted flames of lubricants with additives of calcium, magnesium and ZDDP (Zinc Dialkyl Dithiophosphates) under the hot coflow are recorded with a high-speed camera. The experiments are carried out at one atmospheric pressure and the co-flow temperature varies from 1123 K to 1223 K. The study shows that the ignition delays of lubricants decline sharply with the increase of co-flow temperature in the whole temperature range.
2017-10-08
Journal Article
2017-01-2341
Kongsheng Yang, Kristin A. Fletcher, Jeremy P. Styer, William Y. Lam, Gregory H. Guinther
Abstract Countries from every region in the world have set aggressive fuel economy targets to reduce greenhouse gas emissions. To meet these requirements, automakers are using combinations of technologies throughout the vehicle drivetrain to improve efficiency. One of the most efficient types of gasoline engine technologies is the turbocharged gasoline direct injection (TGDI) engine. The market share of TGDI engines within North America and globally has been steadily increasing since 2008. TGDI engines can operate at higher temperature and under higher loads. As a result, original equipment manufacturers (OEMs) have introduced additional engine tests to regional and OEM engine oil specifications to ensure performance of TGDI engines is maintained. One such engine test, the General Motors turbocharger coking (GMTC) test (originally referred to as the GM Turbo Charger Deposit Test), evaluates the potential of engine oil to protect turbochargers from deposit build-up.
2017-10-08
Journal Article
2017-01-2356
Hyun-Soo Hong, Christopher Engel, Brian Filippini, Sona Slocum, Farrukh Qureshi, Tomoya Higuchi
Abstract Improving vehicle fuel economy is a major consideration for original equipment manufacturers (OEMs) and their technology suppliers worldwide as government legislation increasingly limits carbon dioxide emissions. At the same time that automotive OEMs have been driving toward lower viscosity axle oils to improve fuel economy, OEMs have worked to improved durability over an extended drain interval. These challenges have driven the use of API group III and/or API group IV base oils in most factory fill axle oils. This paper details the development of a novel lower viscosity SAE 75W-85 axle technology based on group II base oil that rivals the performance of a PAO-based axle oil and challenges the conventional wisdom of not using group II base oils in fuel efficient axle oils.
2017-10-08
Journal Article
2017-01-2343
Nicolas Champagne, Nicolas Obrecht, Arup Gangopadhyay, Rob Zdrodowski, Z Liu
Abstract The oil and additive industry is challenged to meet future automotive legislations aimed at reducing worldwide CO2 emissions levels. The most efficient solution used to date has been to decrease oil viscosity leading to the introduction of new SAE grades. However this solution may soon reach its limit due to potential issues related to wear with lower engine oil viscosities. In this paper, an innovative solution is proposed that combines the use of a new tailor-made polyalkylene glycol (PAG) with specific anti-wear additives. Valvetrain wear measurements using radionuclide technique demonstrates the robustness of this solution. The wear performance was also confirmed in Sequence IVA test. An extensive tribological evaluation (film formation, wear and tribofilm surface analysis) of the interactions between the base oil and the anti-wear additives lead us to propose an underlying mechanism that can explain this performance benefit.
2017-10-08
Journal Article
2017-01-2348
Michael Clifford Kocsis, Peter Morgan, Alexander Michlberger, Ewan E. Delbridge, Oliver Smith
Abstract Increasingly stringent fuel economy and emissions regulations around the world have forced the further optimization of nearly all vehicle systems. Many technologies exist to improve fuel economy; however, only a smaller sub-set are commercially feasible due to the cost of implementation. One system that can provide a small but significant improvement in fuel economy is the lubrication system of an internal combustion engine. Benefits in fuel economy may be realized by the reduction of engine oil viscosity and the addition of friction modifying additives. In both cases, advanced engine oils allow for a reduction of engine friction. Because of differences in engine design and architecture, some engines respond more to changes in oil viscosity or friction modification than others. For example, an engine that is designed for an SAE 0W-16 oil may experience an increase in fuel economy if an SAE 0W-8 is used.
2017-10-08
Technical Paper
2017-01-2415
Valery Dunaevsky
Abstract The film thickness-roughness ratio Λ has been used since the mid-1960s as a simplified criterion for the lubrication conditions in rolling bearings. However, due to an assumed Gaussian distribution of the roughness height amplitudes of the functional surfaces of rolling bearings and other unsubstantiated assumptions regarding the mechanisms of contact interaction, concerns have arisen about the representability of Λ in terms of lubrication. In this study, a more objective Λ-type ratio that does not depend on the law of roughness height distribution and the peculiarities of contact mechanics is introduced and defined as Λz. The relevant range of the new Λ ratio is lower than that of its conventional counterpart, and it overlaps with contemporary theoretical and experimental results. The study exhibits unique profilometric data of the functional surfaces of the roller bearings, produced by the major bearing manufacturers.
2017-09-17
Journal Article
2017-01-2480
Roberto Dante, Andrea Sliepcevich, Marco Andreoni, Mario Cotilli
Abstract Tin sulfides (SnS and SnS2), represent a safer and greener alternative to other metal sulfides such as copper sulfides, and MoS2 etc. Their behavior is usually associated to that of solid lubricants such as graphite. A mixture of tin sulfides, with the 65 wt% of SnS2, has been characterized by scanning electron microscopy and by thermal gravimetric analysis (TGA). In order to investigate the effect of tin sulfides upon two crucial friction material ingredients, two mixtures were prepared: the former was made by mixing tin sulfides with a natural flake graphite and the latter was made mixing tin sulfides with a straight novolak. They were analyzed by TGA and differential thermal analysis (DTA) in both nitrogen and air. Some interferences were detected between tin sulfides and graphite in air.
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