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Viewing 91 to 120 of 85301
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
Journal Article
2017-01-2431
Michitaka Yamamoto, Takayuki Hosogi, Tetsuji Watanabe, Yuki Nishida
Abstract Over the past decades, the automotive industry has made significant efforts to improve engine fuel economy by reducing mechanical friction. Reducing friction under cold conditions is becoming more important in hybrid vehicle (HV) and plug-in hybrid vehicle (PHV) systems due to the lower oil temperatures of these systems, which results in higher friction loss. To help resolve this issue, a new internal gear fully variable discharge oil pump (F-VDOP) was developed. This new oil pump can control the oil pressure freely over a temperature range from -10°C to hot conditions. At 20°C, this pump lowers the minimum main gallery pressure to 100 kPa, thereby achieving a friction reduction effect of 1.4 Nm. The developed oil pump achieves a pressure response time constant of 0.17 seconds when changing the oil pressure from 120 kPa to 200 kPa at a temperature of 20°C and an engine speed of 1,600 rpm.
2017-10-08
Technical Paper
2017-01-2359
Yaodong Hu, Fuyuan Yang, Minggao Ouyang
Abstract Energy saving is becoming one of the most important issues for the next generation of commercial vehicles. The fuel consumption limits for commercial vehicles in China have stepped into the third stage, which is a great challenge for heavy duty commercial vehicles. Hybrid technology provides a promising method to solve this problem, of which the dual motor coaxial series parallel configuration is one of the best options. Compared with parallel configuration, the powertrain can not only operate in pure electric or parallel mode, but also can operate in series mode, which shows better flexibility. In this paper, regulations on test cycle, fuel consumption limits and calculation method of the third stage will be introduced in detail. Then, the quasi-static models of the coaxial series parallel powertrain with/without gearbox under C-WTVC (China worldwide transient vehicle cycle) are built. The control strategies are designed based on engine and motor performance.
2017-10-08
Technical Paper
2017-01-2354
Dave Horstman, John Sparrow
Abstract Due to recent legislation on CO2 emissions, Heavy Duty engine and vehicle manufacturers and their suppliers have had an increased interest in improving vehicle fuel economy. Many aspects are being investigated including vehicle aerodynamics, tire rolling resistance, waste heat recovery, engine fuel efficiency, and others. Crankcase oils offer a cost-effective mechanism to reduce engine friction and increase engine fuel efficiency. The potential gains realized by optimized fuel-efficient oils are relatively small, usually less than 3%. Therefore, in order to develop these oils, formulators must have a robust, repeatable, and realistic test method for differentiation. To serve Light Duty (LD) engines, this need has been partially satisfied by the development of what became the Sequence VI engine test for gasoline passenger car oils in the early 1990’s.
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
2017-01-2433
Fengqin Huang, Wenxin CAI, Zhiming Zhang, Wenlong Zhang, Laifeng Shi, Xin Li, Bernhard Kaltenegger, Daniele Suzzi, Werner Schrei, Karl Weihrauch
Abstract Nowadays high thermal efficiency engine is the mainstream of the gasoline engine development, and the control of the design period is strict, which lead to the cylinder head design become more and more difficult. How to get the optimal design of cylinder head quickly is an important research topic by design professionals in the current, which not only meets the performance requirements, but also guarantees the requirement of reliability. The sub-model method is high efficient and high precision in solving the complex problem of stress and strain, which widely used in truss, road, bridge and large container. Using this technology in the local structure optimization of the cylinder head, will shorten the cycle of structure optimization significantly, and get the optimal design of cylinder head quickly. In this paper, Firstly, the cylinder head global FE model was set up.
2017-10-08
Technical Paper
2017-01-2432
Xiangwang Li, Weimin Wang, Xiongcai Zou, Zhiming Zhang, Wenlong Zhang, Shemin Zhang, Tao Chen, Yuhuang Cao, Yuanda Chen
Abstract In order to reduce emissions, size and manufacturing cost, integrated exhaust manifold become popular in gasoline engine, especially in three-cylinder engine. Moreover, due to shorter length, lighter weight, and less component connections, the exhaust manifold and hot end durability will improve apparently. In this work, an advanced cylinder head with integrated exhaust manifold is adopted in a three-cylinder turbo engine. Because of this integration characteristic, the gas retain in cylinder head longer and the temperature reach higher level than normal cylinder head, which will cause thermal fatigue failure more easily. To validate the exhaust manifold and hot end durability, series simulation and test validation work have been done. Firstly, overall steady state and transient temperature simulation was done for global model. For turbocharger, in order to simulate the outlet turbulent flow and 3d rotation, a code was compiled to define this 3d rotation.
2017-10-08
Technical Paper
2017-01-2435
Jian Ji, BoZhou He, Lei Yuan
Abstract It is well-known that, compared with automatic transmissions (ATs), continuously variable transmission (CVT) shows advantages in fuel saving due to its continuous shift manner, since this feature enables the engine to operate in the efficiency-optimized region. However, as the AT gear number increases and the ratio gap narrows, this advantage of CVT is challenged. In this paper, a comparative study on fuel economy for a CVT based vehicle and a 9-speed automatic transmission (AT) based vehicle is proposed. The features of CVT and AT are analyzed and ratio control strategies for both the CVT and 9-speed AT based vehicles are designed from the view point of vehicle fuel economy, respectively. For the 9-speed AT, an optimal gear shift map is constructed. With this gear shift map, the optimal gear is selected as vehicle velocity and driving condition vary.
2017-10-08
Technical Paper
2017-01-2442
Bingqing Xiao, Wei Wu, Jibin Hu, Shihua Yuan, Chenhui Hu
Abstract The prediction of temperature distribution and variation of oil-cooled sliding disk pair is essential for the design of wet clutches and brakes in a vehicle transmission system. A two-phase coupled heat transfer model is established in the study and some fluid-solid coupled heat transfer simulations are performed to investigate the thermal behaviors of wet clutch during sliding by CFD method. Both cooling liquid and grooved solid disks are contained in the heat transfer model and the heat convection due to the cooling liquid in the radial grooves is also considered by fluid-solid coupled transient heat transfer simulations. The temperature distribution and variation of the grooved disk are discussed and analyzed in detail. The results indicate that the temperature distribution on the grooved disk is nonuniform. The temperature within the middle radius area is higher than that in the inner and outer radius area.
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
2017-01-2443
Ziwang Lu, Hongxu Chen, Lijun Wang, Guangyu Tian
Abstract During the engaging process of sleeve and teeth ring in mechanical transmissions, their rotational speed and position differences cause multiple engaging ways and trajectories, and casual impacts between them will delay the engaging process and cause a long power off time for a gear shift. In order to reveal the engaging mechanism of the sleeve and the teeth ring, it is essential to build a high-fidelity model to cover all of their engaging ways and capture their speed changes for an impact. In this work, our contribution is that their impact process is modeled as a precise, continuous and nonlinear damping model, and then a hybrid automaton model is built to connect the system dynamics in different mechanical coupling relationships.
2017-10-08
Technical Paper
2017-01-2355
Yungwan Kwak, Christopher Cleveland
Abstract Due to its simplicity and fuel economy benefit, continuously variable transmission (CVT) technology has gained a lot of attention in recent years. Market penetration of CVT technology is increasing rapidly compared to step-type automatic transmission technology. OEMs, Tier 1 suppliers, and lubricant suppliers are working to further improve the fuel economy benefit of CVTs. As a lubricant supplier, we want to understand the effects of fluid properties on CVT fuel economy (FE). We have formulated fluids that had KV100 ranges from 2-4 cSt to 7-9 cSt with various types and viscosities of base oils. Wide ranges of viscosity indexes, steel-on-steel friction, and other properties were tested. Full vehicle fuel economy tests were performed in a temperature controlled environment with a robotic driver. The test revealed that there was more than 3% overall FE variation compared to a reference fluid.
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
2017-01-2361
David R. Lancaster
Abstract Virtually all developed countries regulate light-duty vehicle emissions and fuel consumption. Those regulations rely on different procedures and driving cycles in testing to different standards in different countries. As a result, it is often very difficult to compare the standards imposed by different countries. This paper utilizes publicly available data to compare the energy requirements of the chassis dynamometer driving cycles in common use throughout the world. It also examines the relative severity of the currently existing light duty vehicle CO2 standards, some of which are mass-based with a targeted fleet average, and some of which are individual vehicle targets based on footprint.
2017-10-08
Technical Paper
2017-01-2183
Xiangfeng Yu, Shengcheng Li, Zhishuang Ma, Wei Du, Fengxiang Huang, Weijun Huang, Beiping Jiang
A reciprocating piston expander model based on organic Rankine cycle (ORC) is built for engine waste heat recovery. The expander characterizes by variable expansion ratio through adjusting refrigerant injection timing. This paper investigates the effect of refrigerant evaporating pressure, expansion ratio and clearance volume on the expander performance which mainly includes output power, expander efficiency, equivalent recovery efficiency, total output power, expander efficiency, weighted efficiency of expender and weighted heat recovery efficiency of expender. The results demonstrate that the total output power and the equivalent heat recovery efficiency increase with refrigerant evaporating pressure under overall operating conditions, while the increment is negligible. The expander reaches maximum total output power up to 83.442kW under c100 engine condition and 1.1MPa refrigerant evaporating pressure within the research operating conditions.
2017-10-08
Technical Paper
2017-01-2212
Jun Peng, Mingyang Ma, Wang Weizhi, Fu-qiang Bai, Qing Du, F Zhang
High-pressure common rail(HPCR)fuel injection system is the most widely used fuel system for diesel engines due to the fact that it can provide constant injection pressure and precise injection strategy. However, when multiple injection strategy is used, the pressure wave caused by the opening and closing of the needle valve will affect the subsequent injection and can not be neglected. In this paper, the influence of pressure wave on the second injection pressure, injection rate and fuel-injection quantity is carried out on a common rail fuel injection test rig under two-stage injection conditions. The results show that the pressure wave varies in terms of various rail pressure, environmental back pressure and injection intervals, resulting in a 10% fluctuation. As a consequence, the injection quantity will be changed. In detail, increasing injection intervals leads to an enhancement of injection pressure, injection pressure fluctuations and the decrease of injection quantity.
2017-10-08
Technical Paper
2017-01-2213
Satoshi Hokimoto, Tatsuya Kuboyama, Yasuo Moriyoshi, Minoru Iida, Takahiro Watanabe
Reduction in the cycle-to-cycle variation (CCV) of combustion in internal combustion engines has been required because CCV affects fuel consumption, emissions and drivability. CCV becomes stronger at low load or lean / diluted burn conditions. Specifically, the factors that cause CCV of combustion are supposed to variations of in-cylinder flow, fuel distribution, temperature distribution, residual gas distribution and ignition energy in each cycle. However, it is impossible to measure and analyze minutely these factors in a production engine. In this study, CCV of the combustion and in-cylinder phenomena in the same cycle of PFI gasoline engine were investigated by using an optical single-cylinder engine. This optical engine can observe the whole combustion chamber by the quartz glass cylinder and pent-roof window. CCV of flow in the cylinder during continuous 45 firing cycles was measured by Time Resolved Particle Image Velocimetry (TR-PIV) technique.
2017-10-08
Technical Paper
2017-01-2215
Mingming Ma
Lubricating oil system models of aero-engine whole process are established by applying ANN based on a large number of flight test data. Model results are in good agreement with flight test results, which shows the feasibility and effectiveness of the presented modeling method. The results of model are applied to the test condition monitoring of the aero-engine lubricating oil system, thus the real-time tendency monitoring of lubricating oil parameters is realized and application. In addition, a method to determine the main influence parameters of aero-engine lubricating oil parameters is developed by using the presented modeling method.
2017-10-08
Technical Paper
2017-01-2214
Kwee-Yan Teh, Penghui Ge, Yusheng Wang, David Hung
The large-scale rotating flow structure in an engine cylinder exhibits features that can be described in generic terms of tumble and swirl. The structural details, nevertheless, vary from cycle to cycle due to fluctuating initial and boundary conditions of the flow. Typical analysis of the flow field cyclic variability — by simple root-mean-square, or additional spatial or temporal filtering, or proper orthogonal decomposition — is based on pointwise deviation of the instantaneous velocity from the ensemble mean. However, that analysis approach is not amenable to the evaluation of spatial variation of the flow structure, in position and orientation, within the flow field. To this end, other studies in the past focused instead on quantifying the variation of the vortex center for the dominant tumble or swirl pattern within the flow field.
2017-10-08
Technical Paper
2017-01-2217
Fushui Liu, Ning Kang, Yikai Li, Pei Wang
The electronic unit pump system, which is widely applied to the heavy-duty diesel engine, belongs to the pulsating high pressure fuel injection system, and the fuel pressure fluctuations have an essential influence on the spray and combustion in the internal combustion engine. Pressure fluctuations are always aroused by the motion of actuators, such as the injector, so it is also an advantage for fault diagnosis and feedback control to ascertain the relationship between the pressure fluctuation and the motion of the actuator. In this study, experiments and 1D simulation were carried on to investigate the fuel pressure fluctuation characteristics and their connection to the transient motion of the needle valve in the injector.
2017-10-08
Technical Paper
2017-01-2216
Yumin Fu
This document presents the development of a methodology for detecting rough road using the frequency analysis of the instantaneous engine speed signal. Combustion diagnosis (misfire detection) is enforced by EOBD/OBD II requirements, and eliminating the rough road driving affect on the diagnosis is critical for getting a robust misfire detection performance, especially for crankshaft speed based misfire diagnosis method. Although some kind of sensor is often used to identify that vehicle is traveling on rough road, the sensor less rough road monitor method is still more attractive for OEM to reduce cost, and some approaches have been developed past for the aim. The new approach presented here is based on the frequency domain analysis of engine speed characteristic excited by rough road traveling, and thus the frequency energy distribution comparison with public road driving and misfire introduced operation condition.
2017-10-08
Technical Paper
2017-01-2221
Peixuan Zeng, Penghao Zhang, Binyu Mei, Shiping Huang, Gangfeng Tan
Abstract:In low temperature condition, the increase of fuel viscosity, the decrease of flow-ability of lubricating oil and the decrease of storage battery performance cause the engine starting difficult. The current electrical heating method can improve the engine starting performance in low temperature condition, but it causes a negative influence on storage battery performance and exhaust emission. In this paper, a warming device uses solar energy to directly warm up the engine. The device transfers solar power into thermal energy and store it into heat reservoir and uses heat conductor to warm up the engine. By using solar power to save power, the lifespan of the engine is extended and exhaust emission is decreased. This paper find out the heat amount necessary for diesel engine through resource gathering and calculation, choose an appropriate device and design a corresponding solar warming system. Keywords: warming system, solar power, diesel engine
2017-10-08
Technical Paper
2017-01-2218
Roman Varbanets, Sergey Karianskyi, Sergey Rudenko, Igor V. Gritsuk, Aleksey Yeryganov, Olena Kyrylash, Nadezhda Aleksandrovskaya
Operability and efficiency of automobiles and infrastructure of stationary power and transport significantly depends on technical condition and technical operation of internal combustion engines, mostly which are diesel engines. Expedient operation of diesel engines in processes holding a timely procedure of parameters monitoring of technical condition and identification, during the work. In the article features of diagnosing of the diesel engine with uniformity of loadings distribution between cylinders provided that of ensuring normal operating state of the fuel units and components of the main systems of the diesel are considered. Results of definition of engine power, efficiency of fuel using and observance of the main ecological restrictions depending on uniformity of distribution of loadings between cylinders are presented. Also in article the main methods of diagnosing of the diesel engine in processes of its work under operating conditions are described.
2017-10-08
Technical Paper
2017-01-2223
Vikram Singh, Per Tunestal, Martin Tuner
In recent years, stricter regulations on emissions and higher demands for more fuel efficient vehicles have led to a greater focus on increasing the efficiency of the internal combustion engine. Nowadays, there is increasing interest in the recovery of waste heat from different engine sources such as the coolant and exhaust gases using, for example, a Rankine cycle. In diesel engines 15% to 30% of the energy from the fuel can be lost to the coolant and hence, does not contribute to producing work on the piston. This paper looks at reducing the heat losses to the coolant by increasing coolant temperatures within a single cylinder Scania D13 engine and studying the effects of this on the energy balance within the engine as well as the combustion characteristics. To do this, a GT Power model was first validated against experimental data from the engine.
2017-10-08
Technical Paper
2017-01-2222
ZhenYang Liu, Xihui Wang
The ever increasing popularity of electric vehicles and demand in passengers comfort and safe requirements of vehicle have led more efficient heat pump air conditioning system to an indispensable device in electric vehicle. Many studies have shown that the addition of nano particles contributes to improving the thermal conductivity of nano fluids more than that of conventional refrigerants. Therefore, the appliance of the magnetic nano-refrigerant in heat pump air conditioning system has great potential to improve the heat transfer efficiency. This paper aims at studying the magnetic nano-refrigerant comprised of the magnetic nano powder Fe3O4 and refrigerant R134a.According to the relevant theoretical analysis and different empirical formula, the heat transfer coefficient, density, viscosity, and other physical parameters are calculated approximately.
2017-10-08
Technical Paper
2017-01-2227
Wei Guan, Vinícius Pedrozo, Hua Zhao, Zhibo Ban, Tiejian Lin
Abstract In order to meet increasingly stringent emissions standards and lower the fuel consumption, significant efforts are being made to develop high efficiency low emission internal combustion engines and after-treatment systems. In addition to the trade-off between thermal efficiency and nitrogen oxides (NOx) emissions, the conversion efficiency of the diesel aftertreatment system decreases rapidly at lower exhaust temperature, which occurs at low load operations. Thus, it is necessary to investigate and identify the appropriate combustion and engine control strategies which can lead to lower vehicle exhaust emission by keeping the engine-out NOx low and NOx aftertreament conversion efficiency high through elevated engine exhaust gas temperature (EGT). In this work, an experimental investigation has been performed using external EGR and Miller cycle achieved by delaying the intake valve closing (IVC) timing on a single cylinder heavy-duty diesel engine.
Viewing 91 to 120 of 85301