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2016-04-05
Technical Paper
2016-01-0670
José Ramón Serrano, Pedro Piqueras, Roberto Navarro, Javier Gómez, Marc Michel, Bénédicte Thomas
Upcoming type approval regulations will force to optimize aftertreatment system to reduce emissions looking for lack of fuel penalty. Despite advances in purely aftertreatment aspects, the performance of the diverse aftertreatment devices is very dependent on the operating temperature. This makes them rely on the engine design and calibration because of the imposed turbine outlet temperature. The need to reach target conversion efficiency and to complete regeneration processes requires controlling additional parameters during the engine setup. For that reason, exploring the potential of different solutions to increase inlet aftertreatment temperature is becoming a critical topic. Nevertheless, such studies cannot be tackled without considering concerns on the engine fuel consumption. In this paper, the influence of several design parameters is studied by modelling approach under steady state operating conditions in a Diesel engine.
2016-04-05
Technical Paper
2016-01-1196
Yazhou GUO, Maji LUO, Jia ZOU, Yunpeng LIU, Jianqiang KANG
Traction batteries are operated in severe working conditions of wide temperature range as the vehicles run in different seasons and regions, which effects battery performance deeply. Investigation on the effect of temperature under such circumstances on battery performance is very significant to promote the application of traction battery. In this paper, some tests are conducted on a ternary-material lithium-ion battery at various temperatures. The cycling performance and some significant parameters are evaluated at the whole temperature range, especially at the extreme temperatures (below -10°C or above 45°C). The results show that the battery performance becomes poor obviously at low temperatures, which is reflected in the decreased terminal voltage and the faded discharge capacity, and at too high temperatures (above 45°C), power and capacity also decrease, which happens in the later discharge process.
2016-04-05
Technical Paper
2016-01-1033
Silvia Marelli, Giulio Marmorato, Massimo Capobianco, Jean-Maxime Boulanger
Turbocharging is playing today a fundamental role not only to improve automotive engine performance, but also to reduce fuel consumption and exhaust emissions for both Spark Ignition and diesel engines. Dedicated experimental investigations on turbochargers are therefore necessary in order to get a better understanding of its performance. The availability of experimental information on realistic turbine steady flow performance is an essential requirement to optimize engine-turbocharger matching calculations developed in simulation models. This aspect is more noticeable as regards turbine efficiency, since its swallowing capacity can be accurately evaluated through the measurement of mass flow rate, inlet temperature and pressure ratio across the machine. Actually, in the case of a turbocharger radial inflow turbine, isentropic efficiency directly evaluated starting from measurement of thermodynamic parameters at the inlet and outlet sections can give significant errors.
2016-04-05
Technical Paper
2016-01-1026
Silvia Marelli, Simone Gandolfi, Massimo Capobianco
Today turbocharging represents a key technology to reduce fuel consumption and exhaust emissions for both Spark Ignition and diesel engines, moreover improving performance. 1D models, generally employed to compute the engine-turbocharger matching conditions, can be optimized due to several information about turbine and compressor behavior required. Because of difficulty in the correctly evaluation of turbine isentropic efficiency with direct techniques, turbocharger turbine efficiency is generally referred to thermo-mechanical efficiency. To this aim, the possibility to accurately estimate power losses in turbocharger bearings can allow to assess turbine isentropic efficiency starting from the thermo-mechanical one. In the paper an experimental and theoretical study on turbocharger mechanical losses is presented. The proposed model, developed in MATLAB environment, refers to radial and axial bearings.
2016-04-05
Technical Paper
2016-01-1072
Peter Schaal, Byron Mason, Sotiris Filippou, Ioannis souflas, Mark Cary
The paper presents a measurement methodology which combines an ultra-fast thermocouple with an input reconstruction technique in order to measure crank angle resolved temperature phenomena in an engine air-intake system. Thermocouples that are of practical use in engine experiments tend to have a large time constant which affects measurement accuracy during rapid temperature transients. Input reconstruction methods have previously been applied for use on larger diameter thermocouples but have not been applied to ultra-thin uninsulated wire thermocouples to investigate cyclic intake temperature behaviour. Accurate measurement results are of interest to improve the validity of many crank-angle resolved engine models. An unshielded thermocouple sensor has been developed which is rigid enough to withstand the aerodynamic forces of the intake air.
2016-04-05
Technical Paper
2016-01-0484
Chad W. Chichester
Silicone fluids are known to have high Viscosity Indices (VI), and high Oxidation Onset Temperatures (OOT). Silicone VI and OOT characteristics make those fluids appealing for use as lubricants in high temperature applications, and where lubricant longevity is desired. Despite thermal and oxidative benefits, silicones lubricants have a reputation as being poor lubricants in metal-to-metal applications, and are typically only selected for use in plastic applications. Most industrial knowledge about silicone lubricants is based on characteristics of PolyDiMethyl Siloxanes (PDMS), in which case, lubricity limitations do exists. However, there are other silicone based lubricating fluid technologies, that have been commercially available for decades, that far exceed known lubricity performance of PDMS, and in some ways can rival traditional synthetic hydrocarbon.
2016-04-05
Technical Paper
2016-01-0105
Yogesh Chandra Sharma
In this technical paper, a conceptual framework for collective thermal behavior of multiple terminals in an electrical connector has been discussed. A terminal in the connector affects ambient temperature of the surrounding cavities due to resistive heat loss of current passing through that terminal by conduction and convection (heat flow mechanisms). Multiple parameters (size, geometry, material, plating etc…) decide thermal property of a terminal. Hence, it is complex to identify the method for each terminal series, which will exhibit the same properties as defined by the manufacturer. To simplify the understanding of this interaction, an alternative method is identified. This method utilizes the manufacturing curves provided by the manufacturer, which include the effects of all the design parameters of terminals. In this method, the important step is to characterize the terminal manufacturing curves.
2016-04-05
Technical Paper
2016-01-1042
Jan Macek, Oldrich Vitek
The ever increasing boost pressure demands and seek for low CO2 emissions call for high efficiency turbochargers, which are perfectly matched to an engine and controlled in operation, especially if highly diluted mixture is used. Correct turbocharger representation, usually performed by maps, should be delivered by turbocharger manufacturers and applied in simulation optimizations. Recently, a broad discussion has been taking place in engine designers’ community on possibilities of measurement of isentropic efficiencies at a turbocharger testbed using hot gas for a turbine. Simultaneously, concepts of high-pulsation exhaust manifolds and asymmetrical turbine scrolls are re-introduced. The paper elucidates the relations between apparent and real turbocharger isentropic efficiencies at steady-flow testbed and their impact on engine cycle optimization by simulation. The hints for a turbocharger representation may be deduced from it. Error analysis starts the explanation.
2016-04-05
Technical Paper
2016-01-0197
Ravi Ranjan, Kaushal Kumar Jha, Lakshmaiah Brahmasani, Parvej Khan
The traditional approach of engine thermal behavior of engine during startup has largely be dependent on experimental studies and high fidelity simulations CFD. However these techniques require considerable effort, cost and time. The low fidelity simulations validated with experimental results becoming popular due to its ease in handling the several parameters, cost effectiveness and quick predictive results. A four point mass model of engine thermal behavior during cold start has been developed to study the engine warm up temperature. The four point mass model consider the lumped mass of coolant, mass of engine directly associated with coolant, mass of engine oil and mass of engine directly associated with engine oil. The advantage of four point model is predict the coolant temperature as well as lubricant temperature during the transient warm cycle of engine. The error between predicated temperatures and experimental are within 10%.
2016-04-05
Technical Paper
2016-01-0232
Zhijia Yang, Edward Winward, Song Lan, Richard Stobart
It is well known that there are approximately two-thirds of fuel energy is rejected as thermal energy in internal combustion engine, one third to the coolant and one third to the exhaust. Thermo-Electric Generator (TEG) is a static solid-state thermal to electricity energy convertor. It is very attractive in the application of engine waste thermal energy harvest because it has no moving parts. Otherwise, it is simple, silent, reliable and scalable. Even though the current commercial thermoelectric material only has 5% thermal efficiency, the research works on new Thermo-Electric Module (TEM) show that thermal efficiency of TEM may possible reach 20% by using quantum well technology and even more may reach maximum 50% by using isolation technology within a TEM. This prediction increases the possibility for TEG becomes one of the important optimization elements in future hybrid vehicle. A one dimensional TEG dynamic model was developed and validated using TEG on engine test data.
2016-04-05
Technical Paper
2016-01-0889
Chuang Fan, Sunyu Tong, Xiaohong Xu, Jing Li, Xiao Yu He, Jun Deng, Liguang Li
Downsizing gasoline direct injection engine with turbo boost technology is the main trend for gasoline engine. However, with engine downsizing and ever increasing of power output, a new abnormal phenomenon, known as pre-ignition or super knock, occurs in turbocharged GDI engine. Pre-ignition will cause very high in-cylinder pressure and high oscillations. In some circumstances, one cycle of severe pre-ignition can damage the piston or spark plug, which has a severe influence on engine performance and service life. So pre-ignition has raised lots of attention in both industry and academic society. More and more studies reveal that the auto-ignition of lubricants is the potential cause for pre-ignition. The auto-ignition characteristics of different lubricants are studied. This paper focuses on the ignition delay of different lubricants in Controllable Active Thermo-Atmosphere (CATA) combustion system.
2016-04-05
Technical Paper
2016-01-0486
Sakthinathan Ganapathy, K R Viswanathan, Saravanan Raju, Anand Kumar Appancheal
The intervention of Nanotechnology in the field of lubricants have found path to several new lubricants for high temperature applications. Nanolubricants are the nanoparticles suspended in base lubricants, are being developed to increase the performance of machine components at high temperatures, which reduces friction and wear in sliding contact encountered in many heat engines and industrial applications. An attempt has been made to study the effect of the Yttria stabilized zirconia(YSZ), Calcia stabilized zirconia(CSZ), and Aluminium oxide nanoparticles in the lube oil base stock. The nanoparticles were synthesized using Ball mill and the nanoparticles were found to be in the range of 50 to 90 nm.
2016-02-04
Standard
J1542_201602
This SAE Recommended Practice is applicable to all liquid-to-air, liquid-to-liquid, air-to-liquid, and air-to-air heat exchangers used in vehicle and industrial cooling systems. This document outlines the tests to determine durability characteristics of the heat exchanger under thermal cycling.
2016-02-01
Technical Paper
2016-28-0168
Prashant Shinde, Omprakash Kota
Abstract Increasing demand of Electric and Hybrid vehicles questions more about Reliability and Lifetime of electronic circuits associated with them. It is very important for a hardware circuit designer to evaluate if module will last the expected lifetime. This paper elaborates the methods and steps to find the expected lifetime of critical components; and to decide whether Hybrid Power Electronics Unit (PEU) will meet the OEM requirements on lifetime. Accelerated thermal stress method is used to determine the required High Temperature Operational Life (HTOL) hours for given thermal profile of Hybrid vehicle passenger car in driving (8,000Hrs), charging(30,000Hrs) and total lifetime (38000Hrs ≈ 15Years). Example calculation of required HTOL hours against expected lifetime for critical component from Hybrid ECUs is explained in this paper. Also inclusions and exclusions of this method in evaluating lifetime assessment are also discussed here.
2015-12-14
WIP Standard
J2412
This test method specifies the operating procedures for a controlled irradiance, xenon arc apparatus used for the accelerated exposure of various automotive interior trim components. Test duration as well as any exceptions to the specimen preparation and performance evaluation procedures contained in this document, are covered in material specifications of the different automotive manufacturers. Any deviation to this test method, such as filter combinations, is to be agreed upon by contractual parties.
2015-11-17
Technical Paper
2015-32-0804
V.R Rajagopalan, S Anand, D Nagendra Kumar, V Karunaharan, V Lakshminarasimhan
Heat flux measurements can provide much needed insight into the energy flow inside an IC engine, which is the key to optimizing its performance. This paper focuses on understanding the nature of heat flux curve and how it varies with varying load conditions, engine speed, Air fuel ratio and ignition timing in a single cylinder, 4 stroke, carbureted, air cooled, spark ignition engine for motorcycle application. In-cylinder heat flux was monitored along with wall temperature and cylinder pressure for motored operation as well as fired conditions. The difference between the motoring mode and fired mode was analyzed to separate out the effects of combustion. In general, the magnitude of maximum heat flux was found to increase with engine rpm and load when all other engine parameters remained constant. The heat flux was found to increase when a mixture setting closer to the stoichiometric value was used.
2015-10-06
Magazine
2016 Malibu sheds 300 lb, adds new hybrid system More wheelbase, style, fuel economy, and comfort aim to move GM's volume midsize sedan from the sidelines to the fast lane. Lighter, more powerful 2016 Honda Pilot The third-generation SUV gets a sleek new look and plenty of slick technology for enhanced performance and safety. 2016 Mazda MX-5 stays true to its roots Mazda engineers give the industry a lesson in getting more from less. 2016 Land Rover Discovery Sport spearheads more efficient Land Rovers JLR's space-efficient, flexible SUV moves to JLR's new Ingenium modular engines. Audi chooses high technology, cautious design evolution for new A4 In addition to lighter weight and significant improvements in efficiency, the new car employs plenty of technology and driver support.
2015-09-06
Technical Paper
2015-24-2449
Mark Aaron Hoffman, Zoran Filipi
The limited operational range of low temperature combustion engines is influenced by near-wall conditions. A major factor is the accumulation and burn-off of combustion chamber deposits. Previous studies have begun to characterize in-situ combustion chamber deposit thermal properties with the end goal of understanding, and subsequently replicating the beneficial effects of CCD on HCCI combustion. Combustion chamber deposit thermal diffusivity was found to differ depending on location within the chamber, with significant initial spatial variations, but a certain level of convergence as equilibrium CCD thickness is reached. A previous study speculatively attributed these spatially dependent CCD diffusivity differences to either local differences in morphology, or interactions with the fuel-air charge in the DI engine. In this work, the influence of directly injected gasoline on CCD thermal diffusivity is measured using the in-situ technique based on fast thermocouple signals.
2015-09-01
Technical Paper
2015-01-1992
Meng-Dawn Cheng
Semi-volatile species in the exhaust can condense on the primary particulate matter (PM) forming significant secondary PM mass downstream1. We developed a new thermographic technique to measure the volatility of a particle population. The instrument is called vapor-particle separator (VPS)2. A two-parameter model was used to interpret the thermographic data3. These two parameters define volatilization potential and thermodynamic capacity of the particles. The volatization potential delineates the unique particle volatility, while the thermodynamic capacity illustrates the work required to eliminate the particles. The thermodynamic capacity is found much smaller for small particles than that for large particles.
2015-09-01
Technical Paper
2015-01-2002
Takeshi Yokomori, Haruko Nagai, Hiroshi Shiratori, Naoki Shino, Naoki Fujisawa, Taro Hirasawa
This study reports a novel alternative technique that can achieve simultaneous two-dimensional temperature and velocity measurements in gas flow. This method is combining phosphor thermometry and PIV operated by a single laser unit. The temperature distribution was obtained from phosphorescence by using two-color method, and the velocity distribution was obtained from two phosphor particle images which were taken in time series during the persistence of the phosphorescence. The measured temperature and velocity were agreed with that measured by thermocouple and that expected as theoretical distribution in the high-temperature gas flows, respectively.
2015-09-01
Technical Paper
2015-01-1999
Nobuyuki Tanaka, Akihiko Kawata
Thermal load caused by engine combustion is one of the important issues for the engines such as high-boosted downsized engines and engines with high compression ratio. In particular, it is necessary to maintain the reliability and durability of exhaust valves which are subject to the biggest thermal impact. For this reason, sodium filled hollow valves are utilized in preference to solid valves in order to decrease the exhaust valve temperature. The most common method for detecting the valve temperature is to estimate the temperature by measuring hardness on valve surface (Hardness test). However, the hardness test is only applicable to the condition up to 800°C. Therefore, this paper presents new techniques for measuring the temperature for sodium-filled valve using infrared thermography and thermocouple as an alternative hardness test. The authors also examined the valve temperatures at a variety of engine speeds and cooling of the sodium-filled valve during engine operation.
2015-09-01
Technical Paper
2015-01-1997
Minhyeok Lee, Kenichi Morimoto, Yuji Suzuki
In this paper, we report the design, fabrication, and performance evaluation of MEMS wireless temperature sensor, which can be applied to the wall temperature measurement in combustors. The sensor is composed of a LCR resonant circuit and its coil is inductively coupled with an external read-out coil for the wireless sensing. Electrical resistance change of the coil due to the temperature change is used to measure the wall temperature. A prototype sensor is fabricated with MEMS technologies and its performance is evaluated in the temperature range of 25 - 200 °C. The measured sensitivity is found to be 2.5 °C at 177 °C, when the distance between the sensor and the readout coil is 1.77 mm.
2015-08-11
Standard
J2412_201508
This test method specifies the operating procedures for a controlled irradiance, xenon arc apparatus used for the accelerated exposure of various automotive interior trim components. Test duration as well as any exceptions to the specimen preparation and performance evaluation procedures contained in this document, are covered in material specifications of the different automotive manufacturers. Any deviation to this test method, such as filter combinations, is to be agreed upon by contractual parties.
2015-05-13
WIP Standard
AIR1657C
Metric (SI and CGS) and English units related to aerospace hydraulics are summarized. Conversion of units is provided as required. Fundamental fluid properties and physical laws governing fluid motion, pressure and other significant aspects are described in SI metric units. Examples of application to typical aerospace hydraulic system components are demonstrated.
2015-05-13
Technical Paper
2015-36-0009
Evandro Benincá, Mauricio da Silva, Ruy Alberto Bueno Jr., Vagner do Nascimento
Abstract One effect which is present in drum and disc brakes is the temperature. This effect significantly changes the vehicle and semi-trailer combinations performance, mainly in drum brakes that is more susceptible to this factor. High temperatures mean loss of efficiency, higher lining wear, brakes and rolling systems components life reduction and could be caused by many factors, which can be mentioned, overload, error in design and choice of brake system, speeding, over adjustment (dragging) and environment heat exchange. The challenge is to comprehend the relation between different brake configuration and how these configurations affects the temperatures generation on brake system, allowing that this factors can be evaluated during the project design. This paper aims to show a case study for a new brake family to be used in city bus application where the fleets are looking for better, safety, performance and low lining wear reduce the to increase the maintenance time.
2015-04-14
Technical Paper
2015-01-0607
Xincheng Liang, Jingshan Zhao
Abstract This paper proposes a theoretical model to interpret the heat generation mechanism and thermal failure of shock absorber. For a common structure of double-tube shock absorber, all frictions between two contacting components of shock absorber are calculated particularly. The heat generation mechanism and heat distribution can be explained with the theoretical model. Thermal failure is a recurrent malfunction for traditional shock absorbers, which leads to shorten the service lives of vehicle components. Heat generation experiments are accomplished to validate the thermal degeneration of shock absorber. So this study is meaningful to develop a new system of vibration attenuation with satisfying reliability, which is essential to improve the riding comfort and handling stability of vehicles.
2015-04-14
Journal Article
2015-01-1157
Namwook Kim, Jongryeol Jeong, Aymeric Rousseau, Henning Lohse-Busch
Abstract For electrified vehicles, understanding the impact of temperature on vehicle control and performances becomes more important than before because the vehicle might consume more energy than conventional vehicles due to lack of the engine waste heat. Argonne has tested many advanced vehicles and analyzed the vehicle level control based on the test data. As part of its ongoing effort, Toyota Prius Plug-in Hybrid was tested in thermal environmental chamber, and the vehicle level control and performances are analyzed by observing the test results. The analysis results show that the control of the Plug-in Hybrid Electric Vehicle (PHEV) is similar with Prius Hybrid Electric Vehicle (HEV) when the vehicle is under a charge sustaining mode, and the vehicle tries to consume the electric energy first under a charge depleting mode.
2015-04-14
Journal Article
2015-01-1525
Rocky Khasow, Scott Best, Martin Agelin-Chaab, John Komar, Gary Elfstrom
Abstract Underbody vehicle flows are poorly understood given the comparatively small field of research to draw upon; even more so in the case of crosswinds. With the advent of electric and hybrid electric vehicles and their increased cooling demands, there is a need for a link between the aerodynamic flow field and the thermodynamic response. Thus underbody research considering a yawing vehicle was conducted on a Chevrolet Aveo5 hatchback. The vehicle was outfitted with a heat source to provide a baseline analysis along thermocouples, pressure probes and flow visualization tufts. The climatic wind tunnel at the University Of Ontario Institute Of Technology's Automotive Centre of Excellence provided video data of the tufts and thermal imaging data of the heat source.
2015-04-14
Journal Article
2015-01-0357
Huize Li, Predrag Hrnjak
Abstract This paper presents a method of utilizing infrared images to quantify the distribution of liquid refrigerant mass flow rate in microchannel heat exchangers, which are widely used in automobile air conditioning systems. In order to achieve quantification, a relationship is built between the liquid mass flow rate through each microchannel tube and the corresponding air side capacity calculated from the infrared measurement of the wall temperature. After being implemented in a heat exchanger model, the quantification method is validated against experimental data. This method can be used for several types of heat exchangers and it can be applied to various heat exchanger designs.
2015-04-14
Technical Paper
2015-01-1673
Seunghyun Lee, Yoonwoo Lee, Sungmoon Lee, Han Ho Song, Kyoungdoug Min, Hoimyung Choi
Abstract In this study, a correlation between the maximum heat release rate and vibrations from a diesel engine block was derived, and a methodology to determine the maximum heat release rate is presented. To investigate and analyze the correlation, an engine test and an actual road vehicle test were performed using a 1.6-L diesel engine. By varying the engine speed, load and main injection timing, the vibration signals from the engine block were measured and analyzed using a continuous wavelet transform (CWT). The results show that the maximum heat release rate has a strong correlation with the magnitude of the vibrations. A specific bandwidth, the vibration signals between 0.3∼1.5 kHz, was affected by the variation in the heat release rate. The vibrations excited by combustion lasted over 50 CAD; however, the signals during the period of 35 CAD after the start of injection had a dominant effect on the maximum heat release rate.
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