Display:

Results

Viewing 1 to 30 of 1109
2016-04-13
WIP Standard
J1961
This test method specifies the operating procedures for using a solar fresnel reflector apparatus for the accelerated exposure of various automotive materials. Sample preparation, test durations, and performance evaluation procedures are covered in material specifications of the different automotive manufacturers.
2016-04-05
Technical Paper
2016-01-1196
Yazhou Guo, Maji Luo, Jia Zou, Yunpeng Liu, Jianqiang Kang
Abstract 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 period of discharge process.
2016-04-05
Technical Paper
2016-01-1072
Peter Schaal, Byron Mason, Sotiris Filippou, Ioannis Souflas, Mark Cary
Abstract The paper presents a measurement methodology which combines a fine-wire thermocouple with input reconstruction in order to measure crank angle resolved temperature 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 to thermocouples but have not been specifically used in combination with an ultra-thin uninsulated wire thermocouple to investigate cyclic intake temperature behavior. 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
2016-01-1088
Julio Carrera
Abstract The increasingly restrictive emission standards in the automotive industry require higher thermal requirements in the EGR loop in terms of gas mass flow, gas temperature and lower coolant flow rate. Also, their performance has to be sustained over a longer period of time. Therefore, thermal load for EGR components, especially EGR coolers, has been increased and thermal fatigue durability is now a critical issue during their development. One of the most challenging issues during product validation is to define a thermal fatigue test with the same field cumulative fatigue damage in order to guarantee durability during vehicle life. A new analytical procedure has been developed in order to define the equivalent thermal fatigue test which has the same cumulative damage as the real application in the field or to estimate durability in the field on the basis of a previous thermal fatigue test result.
2016-04-05
Technical Paper
2016-01-1042
Jan Macek, Oldrich Vitek
Abstract The boost pressure demands call for high efficiency turbochargers. Perfect matching to an engine and controlling in operation is a prerequisite, especially if highly diluted mixture is used. The main impact on four-stroke engine efficiency is performed via gas exchange work, Correct turbocharger representation, usually performed by maps, should be delivered by turbocharger manufacturers and applied in simulation optimizations. The robust calibration methods are required for fast-running real time simulations used for model-based control. The paper clarifies the relations between apparent and real turbocharger isentropic efficiencies at steady-flow testbed and their impact on engine cycle optimization by simulation. Simple procedures excluding the impact of heat transfer inside a turbocharger are described. The described methods are based on the use of overall turbocharger efficiency.
2016-04-05
Technical Paper
2016-01-1033
Silvia Marelli, Giulio Marmorato, Massimo Capobianco, Jean-Maxime Boulanger
Abstract 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 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
Abstract 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 basing on certain information about turbine and compressor behavior. Because of difficulty in the correct evaluation of turbine isentropic efficiency with direct techniques, turbocharger turbine efficiency is generally referred to thermomechanical efficiency. To this aim, the possibility to accurately estimate power losses in turbocharger bearings can allow the assessment of the turbine isentropic efficiency starting from the thermomechanical one. In the paper, an experimental and theoretical study on turbocharger mechanical losses is presented. The proposed model, developed in the MATLAB environment, refers to radial and axial bearings.
2016-04-05
Technical Paper
2016-01-0232
Zhijia Yang, Edward Winward, Song Lan, Richard Stobart
Abstract Two identical commercial Thermo-Electric Modules (TEMs) were assembled on a plate type heat exchanger to form a Thermoelectric Generator (TEG) unit in this study. This unit was tested on the Exhaust Gas Recirculation (EGR) flow path of a test engine. The data collected from the test was used to develop and validate a steady state, zero dimensional numerical model of the TEG. Using this model and the EGR path flow conditions from a 30% torque Non-Road Transient Cycle (NRTC) engine test, an optimization of the number of TEM units in this TEG device was conducted. The reduction in fuel consumption during the transient test cycle was estimated based on the engine instantaneous Brake Specific Fuel Consumption (BSFC). The perfect conversion of TEG recovered electrical energy to engine shaft mechanical energy was assumed. Simulations were performed for a single TEG unit (i.e. 2 TEMs) to up to 50 TEG units (i.e. 100 TEMs).
2016-04-05
Technical Paper
2016-01-0670
José Ramón Serrano, Pedro Piqueras, Roberto Navarro, Javier Gómez, Marc Michel, Bénédicte Thomas
Abstract Upcoming emissions 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
2016-01-0201
Armin Traussnig, Wilko Jansen, Heinz Petutschnig, Sepp Steiner, Petra Gruen
Abstract In order to meet current and future emission and CO2 targets, an efficient vehicle thermal management system is one of the key factors in conventional as well as in electrified powertrains. Global vehicle simulation is already a well-established tool to support the vehicle development process. In contrast to conventional vehicles, electrified powertrains offer an additional challenge to the thermal conditioning: the durability of E-components is not only influenced by temperature peaks but also by the duration and amplitude of temperature swings as well as temperature gradients within the components during their lifetime. Keeping all components always at the preferred lowest temperature level to avoid ageing under any conditions (driving, parking, etc.) will result in very high energy consumption which is in contradiction to the efficiency targets.
2016-04-05
Technical Paper
2016-01-0197
Ravi Ranjan, Kaushal Kumar Jha, Lakshmaiah Brahmasani, Parvej Khan
Abstract The traditional approach of engine thermal behavior of engine during startup has largely been dependent on experimental studies and high fidelity simulations like CFD. However, these techniques require considerable effort, cost and time. The low fidelity simulations validated with experimental results are becoming more popular due to their ease in handling the several parameters such as 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 behavior. The four point mass model considers the lumped mass of coolant, mass of engine directly associated with the coolant, mass of engine oil and mass of engine directly associated with the engine oil. The advantage of four point model is to predict the coolant temperature as well as lubricant temperature during the transient warm up cycle of the engine.
2016-04-05
Journal Article
2016-01-0192
Alaa El-Sharkawy, Ahmed Uddin
Abstract Engine mount is one of the temperature sensitive components in the vehicle under-hood. Due to increasing requirements for improved fuel economy, the under-hood thermal management has become very challenging in recent years. In order to study the effects of material thermal degradation on engine mount performance and durability; it is required to estimate the temperature of engine mount rubber during various driving conditions. The effect of temperature on physical properties of natural rubber can then be evaluated and the life of engine mount can be estimated. In this paper, a bench test is conducted where the engine mount is exposed to a step change in the environment around it, and the temperature of the rubber section is recorded at several points till a steady state temperature is reached. A time response curve is generated, from which a time constant is determined.
2016-04-05
Technical Paper
2016-01-0503
Evandro Giuseppe Betini, Francisco Carlos Cione, Cristiano Stefano Mucsi, Marco Antonio Colosio, Jesualdo Luiz Rossi, Marcos Tadeu D'Azeredo Orlando
Abstract This paper reports the experimental efforts in recording the 2-dimensional temperature distribution on autogenous thin plates of UNS S32304 steel during welding. The butt-welded autogenous joints were experimentally performed by the GTAW (Gas Tungsten Arc Welding) process with either argon or argon-2%nitrogen atmospheres. The temperatures cycles were recorded by means of thermocouples embedded by spot welding on the plate's surfaces and connected to a multi-channel data acquisition system. The laser flash method (LFM) was also used for the determination thermal diffusivity of the material in the thickness direction. The temperature curves suggest a relationship between the microstructures in the solidified and the heat affected zone with the diffusivity variation. This is a region where there had been a major incidence of heat. The obtained results validate the reliability of the experimental used apparatus.
2016-04-05
Technical Paper
2016-01-1403
Jeff D. Colwell, Christopher D. Henry
Abstract Data from a full-scale vehicle burn test involving a cargo van illustrated how temperature distributions changed over time, the manner in which fire spread, and how patterns produced correlated to the origin of the fire. The fire was initiated on the driver’s side of the engine compartment and initially grew slowly with the high-temperature zone near the area of origin. Once the peak temperature reached about 540°C, the rate of flame spread increased such that over the next 4 minutes the fire spread across the entire engine compartment. In the next stage of the fire, which occurred shortly after full involvement of the engine compartment, the fire spread into the passenger compartment. A strong vertical temperature gradient developed from the ceiling to the floor and as the passenger compartment became fully involved, the passenger compartment temperatures both increased and became more uniform.
2016-04-05
Journal Article
2016-01-0578
Giuseppe Cicalese, Fabio Berni, Stefano Fontanesi
Abstract New SI engine generations are characterized by a simultaneous reduction of the engine displacement and an increase of the brake power; such targets are achieved through the adoption of several techniques such as turbocharging, direct fuel injection, variable valve timing and variable port lengths. This design approach, called “downsizing”, leads to a marked increase in the thermal loads acting on the engine components, in particular on those facing the combustion chamber. Hence, an accurate evaluation of the thermal field is of primary importance in order to avoid mechanical failures. Moreover, the correct evaluation of the temperature distribution improves the prediction of pointwise abnormal combustion onset.
2016-04-05
Technical Paper
2016-01-0484
Chad W. Chichester
Abstract Silicone fluids are known to have high Viscosity Indices (VI), and high Oxidation Onset Temperatures (OOT). Silicone VI and OOT characteristics make these 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
2016-01-0486
Sakthinathan Ganapathy, K R Viswanathan, Saravanan Raju, Anand Kumar Appancheal
Abstract 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.
2016-04-05
Technical Paper
2016-01-0766
Tongyang Gao, Marko Jeftic, Geraint Bryden, Graham Reader, Jimi Tjong, Ming Zheng
Abstract The control of nitrogen oxide and smoke emissions in diesel engines has been one of the key researches in both the academia and industry. Nitrogen oxides can be effectively suppressed by the use of exhaust gas recirculation (EGR). However, the introduction of inert exhaust gas into the engine intake is often associated with high smoke emissions. To overcome these issues there have been a number of proposed strategies, one of the more promising being the use of low temperature combustion enabled with heavy EGR. This has the potential to achieve simultaneously low emissions of nitrogen oxide and smoke. However, a quantitative way to identify the transition zone between high temperature combustion and low temperature combustion has still not been fully explored. The combustion becomes even more complicated when ethanol fuel is used as a partial substitution for diesel fuel.
2016-04-05
Journal Article
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 engines. Pre-ignition will cause very high in-cylinder pressure and high oscillations. In some circumstances, one cycle of severe pre-ignition may 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 source 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
2016-01-0105
Yogesh Chandra Sharma
Abstract This technical paper aims to provide a framework for simulating the thermal behavior of an automotive electrical connector with the current flow across each terminal. An automotive electrical connector uses multiple terminals fitted in the respective cavity of a connector. Temperature at terminal increases with the current flow level across it. This temperature rise occurs due to resistive heat loss in the terminal. Due to this, temperature in the surrounding cavities also rises; hence, the current carrying capacity of those cavities reduces. Analysis of similar scenarios for design alternatives and design decisions is important to develop reliable and optimized solutions. The reliable and optimized solution helps to save the cost. There is a large variation of different terminals used in the wiring harness, and there are various parameters attributing to this variation (shape, size, material, plating etc…).
2016-03-23
WIP Standard
J2230
This SAE Standard specifies operating procedure for the exposure of automotive interior trim materials in an outdoor behind-glass apparatus in which the temperature is controlled in a 24 h cycle. The humidity is controlled during the dark (night) portion of the cycle. Specimen preparation, test durations, and performance evaluation procedures are covered in material specifications of the different automotive manufacturers.
2016-03-11
Standard
J1597_201603
This SAE Recommended Practice is applicable to all liquid-to-gas, liquid-to-liquid, gas-to-gas, and gas-to-liquid heat exchangers used in vehicle and industrial cooling systems. This document outlines the tests to determine durability characteristics of the heat exchanger under pressure cycling.
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.
Viewing 1 to 30 of 1109

Filter