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Viewing 181 to 210 of 10086
2015-04-14
Journal Article
2015-01-0671
Saeed Jahangirian, Ashutosh Srivastava, Seyed Alireza Hosseini, Steven Ballard, Naiqiang Wu, John Kiedaisch
Abstract Durability assessments of modern engines often require accurate modeling of thermal stresses in critical regions such as cylinder head firedecks under severe cyclic thermal loading conditions. A new methodology has been developed and experimentally validated in which transient temperature distributions on cylinder head, crankcase and other components are determined using a Conjugate Heat Transfer (CHT) CFD model and a thermal finite element analysis solution. In the first stage, cycle-averaged gas side boundary conditions are calculated from heat transfer modeling in a transient in-cylinder simulation. In the second stage, a steady-state CHT-CFD analysis of the full engine block is performed. Volume temperatures and surface heat transfer data are subsequently transferred to a thermal finite element model and steady state solutions are obtained which are validated against CFD and experimental results.
2015-04-14
Journal Article
2015-01-1379
Hideki Matsumura, Shinichiro Itoh, Kenichi Ando
Abstract Lithium-ion cells are being used in an increasing number of electric and hybrid vehicles. Both of these vehicle types contain many cells. Despite various safety measures, however, there are still reports of accidents involving abnormal heat, smoke, and fire caused by thermal runaway in the cells. If thermal runaway in one cell triggers that of another and thus causes thermal runaway propagation, this can lead to rupture of the battery pack, car fire, or other serious accidents. This study is aimed to ensure the safety of vehicles with lithium-ion cells by clarifying such accident risks, and so we investigated the process of thermal runaway propagation. In the experiment, we created a battery module made of seven laminate-type cells tightly stacked one on another. Then, we induced thermal runaway in one of the cells, measured the surface temperatures of the cells, and collected video data as the process developed. As a result, all of the seven cells underwent thermal runaway.
2015-04-14
Journal Article
2015-01-1391
Scott Allen Ziolek, Joshua Pryor, Tony Schwenn, Adam Steinman
Abstract Optimizing climate seat systems requires increased complexity in seat design which in turn is driving a need for more detailed thermal simulation methods. This paper presents the model development considerations and results of a thermal simulation study aimed at improving the thermal seat comfort experience of Hyundai-Kia's heated seating systems.
2015-04-14
Journal Article
2015-01-1392
Se Jin Park, Seung Nam Min, Murali Subramaniyam, Heeran Lee, Yu Kyung Shin, Chang Hee Jang, Soon Hyun Hwang
Abstract Driving posture measurement is essential for the evaluation of a driver workspace and for improved seat comfort design. This study captures the comfortable driving postures for Koreans using a handheld portable Artec L™ 3D scanner. Subjects consisted of 20 healthy individuals (10 males and 10 females) ranging in age from 20 to 40 years and grouped as three weight groups (<59 kg, 60-79 kg and >80 kg). Eighteen land markers were attached (car seat: 9 markers; subject: 9 markers). From the 3D scanned data, the angles (neck, back, headrest, seat back, wrist, elbow, knee, and ankle) and distances (head to headrest, seat height, and seat back and forth) between the land markers were extracted in the Rapidform XOR software. The body pressure distribution was measured using two pressure mats from 17 body part regions. The measured pressure data were analyzed for average pressure, contact area, and body part pressure ratio.
2015-04-14
Journal Article
2015-01-1526
Yasuyuki Onishi, Thomas Ramsay, Timothy Juan, James McKillen
Abstract A sports car exhibits many challenges from an aerodynamic point of view: drag that limits top speed, lift - or down force - and balance that affects handling, brake cooling and insuring that the heat exchangers have enough air flowing through them under several vehicle speeds and ambient conditions. All of which must be balanced with a sports car styling and esthetic. Since this sports car applies two electric motors to drive front axle and a high-rev V6 turbo charged engine in series with a 9-speed double-clutch transmission and one electric motor to drive rear axle, additional cooling was required, yielding a total of ten air cooled-heat exchangers. It is also a challenge to introduce cooling air into the rear engine room to protect the car under severe thermal conditions. This paper focuses on the cooling and heat resistance concept.
2015-04-14
Journal Article
2015-01-1689
Xu Song, Ryan Fortier, Scott Sarnia
The underhood hot air recirculation greatly impacts A/C system performance at idle and low vehicle speed conditions. The hot air recirculation can raise condenser inlet air temperature in some cases as much as 18°C above ambient, which lowers condenser cooling capacity and increases compressor work. Underhood airflow research in the following study suggests that a properly designed air duct is able to minimize hot air recirculation and improve the Compressors Coefficient of Performance (COP) at idle by 27%. This paper discusses underhood hot air recirculation testing methods, airflow distribution, air duct design concepts, as well as the cross wind and wind tunnel effects. This dedicated air duct design indicates it should improve A/C emissions, which could contribute to meeting the Environmental Protection Agency's (EPA) Green House Gas Emissions Regulations in North America.
2015-04-14
Journal Article
2015-01-1709
Daniel Leighton
Abstract Electric drive vehicles (EDVs) have complex thermal management requirements not present in conventional vehicles. In addition to cabin conditioning, the energy storage system (ESS) and power electronics and electric motor (PEEM) subsystems also require thermal management. Many current-generation EDVs utilize separate cooling systems, adding both weight and volume, and lack abundant waste heat from an engine for cabin heating. Some use battery energy to heat the cabin via electrical resistance heating, which can result in vehicle range reductions of 50% under cold ambient conditions. These thermal challenges present an opportunity for integrated vehicle thermal management technologies that reduce weight and volume and increase cabin heating efficiency. Bench testing was conducted to evaluate a combined fluid loop technology that unifies the cabin air-conditioning and heating, ESS thermal management, and PEEM cooling into a single liquid coolant-based system.
2015-04-14
Journal Article
2015-01-1263
Kenichiro Ikeya, Masanobu Takazawa, Taketo Yamada, Shinrak Park, Ryutaro Tagishi
Abstract The goal of this research was to improve thermal efficiency under conditions of stoichiometric air-fuel ratio and 91 RON (Research Octane Number) gasoline fuel. Increasing compression ratio and dilution are effective means to increase the thermal efficiency of gasoline engines. Increased compression ratio is associated with issues such as slow combustion, increased cooling loss, and engine knocking. Against these challenges, a higher stroke-bore ratio (S/B ratio) and a lower effective compression ratio were tried as countermeasures. With respect to increased dilution, combustion of a high-EGR (Exhaust Gas Recirculation) was tried. High-energy ignition and optimized combustion chamber shape with high tumble port were tried as countermeasures against slow combustion and reduced ignitability due to a higher EGR rate.
2015-04-14
Journal Article
2015-01-1611
Wei Liu, Gangfeng Tan, Xuexun Guo, Jiafan Li, Yuanqi Gao, Wei Li
Abstract The hydraulic retarder is the most stabilized auxiliary braking system [1-2] of heavy-duty vehicles. When the hydraulic retarder is working during auxiliary braking, all of the braking energy is transferred into the thermal energy of the transmission medium of the working wheel. Theoretically, the residual heat-sinking capability of the engine could be used to cool down the transmission medium of the hydraulic retarder, in order to ensure the proper functioning of the hydraulic retarder. Never the less, the hydraulic retarder is always placed at the tailing head of the gearbox, far from the engine, long cooling circuits, which increases the risky leakage risk of the transmission medium. What's more, the development trend of heavy load and high speed vehicle directs the significant increase in the thermal load of the hydraulic retarder, which even higher than the engine power.
2015-04-14
Journal Article
2015-01-1652
Yukikatsu Ozaki, Keisuke Sekiya
Abstract This research developed a new measurement technology for thermal analysis of the heat radiation from a hybrid transaxle case surface to the air and improved the heat radiation performance. This heat flux measurement technology provides the method to measure heat flux without wiring of sensors. The method does not have effects of wiring on the temperature field and the flow field unlike the conventional methods. Therefore, multipoint measurement of heat flux on the case surface was enabled, and the distribution of heat flux was quantified. To measure heat flux, thermal resistances made of plastic plates were attached to the case surface and the infrared thermography was used for the temperature measurement. The preliminary examination was performed to confirm the accuracy of the thermal evaluation through heat flux measurement. The oil in the transaxle was heated and the amount of heat radiation from the case surface was measured.
2015-04-14
Journal Article
2015-01-1656
Lisa Henriksson, Peter Gullberg, Erik Dahl, Lennart Lofdahl
Abstract This article presents Computational Fluid Dynamics (CFD) simulations fo one period of a louvered fin, for a crossflow compact finned heat exchanger, where the incoming airflow was inclined relative to its core. Four inclinations were investigated: 90°, which was when the air flowed perpendicular to the heat exchanger, 60°, 30° and 10° angles relative to the vertical plane. The study included three heat exchanger designs, where two of them had symmetrical louvered fins and a thickness of 19mm and 52mm. The third had a thickness of 19mm and had the louvers angled in one direction. All heat exchangers have been simulated when the airflow entered both from above and below relative to the horizontal plane. Simulations have also been carried out when the airflow entered from the side, illustrating the heat exchanger to be angled relative to the vertical axis. Two air speeds have been investigated for each configuration, where the results were compared to experimental data.
2015-04-14
Journal Article
2015-01-1654
Billy G. Holland, Thomas L. McKinley, Bill R. Storkman
Abstract Cooled EGR continues to be a key technology to meet emission regulations, with EGR coolers performing a critical role in the EGR system. Designing EGR coolers that reliably manage thermal loads is a challenge with thermal fatigue being a top concern. The ability to estimate EGR cooler thermal fatigue life early in the product design and validation cycle allows for robust designs that meet engine component reliability requirements and customer expectations. This paper describes a process to create an EGR cooler thermal fatigue life model. Components which make up the EGR cooler have differing thermal responses, consequently conjugate transient CFD must be used to accurately model metal temperatures during heating and cooling cycles. Those metal temperatures are then imported into FEA software for structural analysis. Results from both the CFD and FEA are then used in a simplified numerical model to estimate the virtual strain of the EGR cooler.
2015-04-14
Journal Article
2015-01-1661
Anthony Levillain, Pascale Brassart, Béatrice Patte-Rouland
Abstract New directives and increasing competition push OEMs to get better performances (engine power increase), along with mass and size reduction (consumption). These evolutions lead to an increase of the thermal solicitations undergo by the clutches whereas their weight must be decreased, as it is one of the main influent factor on CO2 emissions. As the compactness is even more reduced for a Double Dry Clutch (DDC), this issue is critical. In order to improve the thermal behavior of the DDC, a CFD study has been performed. The present paper will introduce the first results obtained with a validated CFD model. The computations are performed on a DDC where the air flow around the rotating parts, along with the convection and the conduction of all solid parts are modeled. Then four different cases are used to evaluate the impact of holes on the air flow path and on the thermal behavior of the different parts of the system.
2015-04-14
Journal Article
2015-01-1691
Manabu Matsumoto, Masayoshi Mori, Tomohide Haraguchi, Makoto Ohtani, Tomoya Kubo, Kanji Matsumoto, Hiroshi Matsuda
Abstract Exhaust heat recovery units that use a thermoelectric element generate electricity by creating a temperature difference in the thermoelectric element by heating one side and cooling the other side of the thermoelectric circuit (module). In this case, the general structure does not directly join the thermoelectric module with the heat sink, and instead presses the thermoelectric module against the heat sink using bolts or other means in order to prevent thermoelectric element damage due to the difference in linear expansion between the cooled and heated sides of the thermoelectric module. However, this poses the issues associated with a complex, heavy and expensive structure. Therefore, a new vacuum space structure was devised that houses the thermoelectric module in a vacuum chamber and presses the module against the heat sink using atmospheric pressure.
2015-04-14
Journal Article
2015-01-0786
Keita Arato, Teruyuki Takashima
Abstract A method to improve fuel consumption in diesel engines is to enhance their theoretical thermal efficiency by increasing their compression ratio. However, this results in an increase in heat loss due to the elevation of the concomitant in-cylinder temperature and the expansion of the impingement area between fuel spray and chamber wall. Therefore, reducing heat loss to the chamber wall is important to effectively benefit from a high compression ratio. To meet this challenge, in this study, we optimized the combustion chamber shape using the three-dimensional computational fluid dynamics (CFD) simulation software, CONVERGE. A rationale proposed by the University of Wisconsin-Madison was selected to outline the shape and combined with a multiobjective optimization software, modeFRONTIER. The calculations produced a shallow dishlike combustion chamber comprising a plateau at its center that may reduce heat loss.
2015-04-14
Technical Paper
2015-01-1122
Kengo Yabe, Toru Inagaki, Takashi Kondo
Abstract Seat vibration when a vehicle is idling or in motion is an issue in automobile development. In order to reduce this vibration, dynamic damper or inertia mass is widely used. These countermeasures increases vehicle's weight and causes bad fuel-efficiency. Some new ways to reduce the vibration without weight increase are needed. One of that is the floating seat. Seat vibration has been reduced by controlling seat resonance frequencies. In order to control resonance frequency, the structures of the seat-mounting unit are replaced with floating structures using rubber bushings. It was demonstrated that partially replacing the mounting unit with floating structures makes it possible to control the resonance frequencies of the entire seat. The issue of balancing vibration reduction with strength and durability and crash safety performance caused by the fitting of rubber bushings to the seat-mounting unit was addressed using stopper structures optimized for each type of input.
2015-04-13
Article
Halla Visteon Climate Control Corp. (HVCC) recently began production at its new facility in Sanand, in the state of Gujarat, India. The full-line supplier of automotive thermal management solutions is using the Gujarat facility to support its growing business with global vehicle manufacturers and to cater to the requirements of OEMs in the state of Gujarat and western India.
2015-04-13
Article
Southco's Bob Straka believes the desire for increased ergonomics and streamlined, aerodynamic equipment designs are leading factors influencing the future of off-highway design.
2015-04-09
WIP Standard
J3094
Create a standard for measurement of the performance characteristics of an Internal Heat Exchanger. The standard should make it easier to innovate designs and bring improvements to this new technology.
2015-04-01
Article
GM's all-new premium flagship sedan is about 200 lb (91 kg) lighter than the BMW 5 Series but offers the interior volume of the short-wheelbase 7 Series, thanks to what is arguably the industry’s most aggressive combination of lightweight materials, forming technologies, and new joining methods in a non-exotic sedan.
2015-04-01
Journal Article
2015-01-9151
Eric S. Winkel, Daniel E. Toomey, Robert Taylor
Abstract Thoracolumbar vertebral fractures are most commonly due to compressive loading modes and associated with falls from height. Two injury metrics are generally referenced for assessing the potential for compressive thoracolumbar injury; the Dynamic Response Index (DRI) and the compressive load measured between the pelvis and lumbar spine using the Code of Federal Regulations (CFR) title 49 part 572 subpart B anthropomorphic test device (ATD). This study utilizes an ATD to investigate the injury mitigation potential of a variety of seat cushions during vertical impact in an unrestrained seated posture. ATD responses and DRI are reported for 65 vertical impacts with and without cushions from heights between 4 and 80 inches. The cushions investigated reduced ATD peak pelvic acceleration 63 +/− 11% and compressive lumbar load 42 +/− 9% on average.
2015-03-31
WIP Standard
AS50571B
This specification covers the general requirements for red and white individual instrument lights. This document has been streamlined. Appendix A to MIL-L-5057F lists those documents required for MIL-L-5057F acquisition and is a mandatory part of MIL-L-5057F. Those documents listed in Appendix A have the same status as those referenced directly in MIL-L-5057F (first tier documents). All other documents, referenced through tiering, may be used as guidance and information to supplement MIL-L-5057F. This document’s scope is limited to lamp source designs solely. Furthermore, the use of red lighting should not be considered for new design and included within this document to support requirements for existing military aircraft that still operate with this system of lighting.
2015-03-30
Book
T. Yomi Obidi
With new and more stringent standards addressing emission reduction and fuel economy, the importance of a well-developed engine thermal management system becomes even greater. With about 30% of the fuel intake energy dissipated through the cooling system and another 30% through the exhaust system, it is to be expected that serious research has been dedicated to this field. Thermal Management in Automotive Applications, edited by Dr. T. Yomi Obidi, brings together a focused collection of SAE technical papers on the subject. It offers insights into how thermal management impacts the efficiency of engines in heavy vehicles, the effects of better coolant flow control, and the use of smart thermostat and next-generation cooling pumps. It also provides an in-depth analysis of the possible gains in optimum warm-up sequence and thermal management on a small gasoline engine.
2015-03-27
Standard
J1819_201503
The scope of this SAE Recommended Practice is to promote compatibility between child restraint systems and vehicle seats and seat belts. Design guidelines are provided to vehicle manufacturers for certain characteristics of seats and seat belts, and to child restraint system (CRS) manufacturers for corresponding CRS features so that each can be made more compatible with the other. The Child Restraint System Accommodation Fixture, shown in Figure 1, is used to represent a CRS to the designers of both the vehicle interior and the CRS for evaluation of each product for compatibility with the other. The features of the accommodation fixture are described as each is used. A CRS accommodation template of transparent plastic, not shown, represents the side of the accommodation fixture for use in approximating its installed position on design drawings.
2015-03-24
Article
Southco introduces the AC-50 squeeze-handle actuator, featuring a squeeze-to-operate actuation and a curved design.
2015-03-23
Article
Lesswire’s Wi4Upro is an updated long-term evolution (LTE) Wi-Fi router with built-in media server for high-speed Internet and entertainment in vehicles.
2015-03-12
Article
BASF offers low-emissions Acrodur Power 2750 X binder for lightweight automotive composites with integrated functions.
2015-03-10
Technical Paper
2015-01-0018
Dongwon Yeon
Abstract There are some problems “windows fog up a lot” for ventilation system. We have Test Development Procedure to prevent the fog problems. But, Many fog problems occurred in the cars that we made. So in this paper, new ventilation system is needed and developed. The Smart Ventilation System automatically controls indoor air quality even though the blower motor is off. There are two sensors that is used for AutoDefogSensor system and CO2 CONTROL system.. The sensor is on when blower motor and heater control is off. We use these signals and make new ventilation logics. We evaluate this system in chamber & '13 winter test in USA.
2015-03-10
Technical Paper
2015-01-0034
Mingyu Choi
Abstract The need for a voice recognition system in the automotive industry is growing day by day. In our current voice recognition system, Hyundai's ‘Blue-Link’ and KIA's ‘UVO’ are developed with Microsoft which is a global software company. The system launched domestic market recently. Since usage of voice recognition system are increasing, research and development of Voice Recognition system also increase very fast. Research is mostly focus on increase recognition rate of speech. However there is no research of interior layout considering voice recognition usability. So in this research, we discover interior design factors for maximizing voice recognition usability.
2015-03-10
Technical Paper
2015-01-0030
Aditya Mulemane, Lachlan Hurst, Alex Fraser, Jarrod Sinclair
Using conventional solvers, the simulation of a complex and large system such as the automotive paint ovens can be quite time consuming - of the order of a several weeks or even months. A reduced order computational model of the oven that can predict thermal distribution quicker is useful in performing optimization studies and in directing finer design changes to the oven and the car body. This research focuses on the development of such a lumped capacitance thermal model (defined here in as the reduced order model: ROM) for predicting the heat of curing of an object that is inside an industrial oven. Essentially, the heat transfer modes are computed through a set of linear ordinary differential equations, by conceptualising the the physical object is conceptualised as a series of inter-connecting nodes that are linked by thermal resistors.
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