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Viewing 181 to 210 of 10346
2016-04-05
Journal Article
2016-01-0656
Jung Hyun Kim, Taewoo Kim, SungJin Park, JungJae Han, Choongsoo Jung, Young rock Chung, Sangsoo Pae
Abstract In cold start driving cycles, high viscosity of the lubrication oil (engine oil) increases the mechanical friction losses compared with warmed up condition. Thus, an engine oil warm up system can provide the opportunity to reduce the mechanical friction losses during cold start. In this study, an engine oil heater using EGR is used for the fast warm up of the engine oil. This paper presents the effect of the engine oil heater on the fuel economy and emissions over a driving cycle (NEDC). A numerical model is developed to simulate the thermal response of the powertrain using multi-domain 1-D commercial powertrain simulation software (GT-Suite) and it is calibrated using test data from a full size sedan equipped with a 2.0L diesel engine. The model consists of an engine model, coolant circuit model, oil circuit model, engine cooling model, friction model, and ECU model.
2016-04-05
Technical Paper
2016-01-0655
Farid Bahiraei, Amir Fartaj, Gholm-Abbas Nazri
In this work, a pseudo three-dimensional coupled thermal-electrochemical model is established to estimate the heat generation and temperature profiles of a lithium ion battery as functions of the state of the discharge. Then, this model is used to investigate the effectiveness of active and passive thermal management systems. The active cooling system utilizes cooling plate and water as the working fluid while the passive cooling system incorporates a phase change material (PCM). The thermal effects of coolant flow rate examined using a computational fluid dynamics model. In the passive cooling system, Paraffin wax used as a heat dissipation source to control battery temperature rise. The effect of module size and battery spacing is studied to find the optimal weight of PCM required. The results show that although the active cooling system has the capability to reduce the peak temperatures, it leads to a large temperature difference over the battery module.
2016-04-05
Journal Article
2016-01-0661
Yoshifumi Wakisaka, Minaji Inayoshi, Kenji Fukui, Hidemasa Kosaka, Yoshihiro Hotta, Akio Kawaguchi, Noriyuki Takada
The reduction of the heat loss from the in-cylinder gas to the combustion chamber wall is one of the key technologies for improving the thermal efficiency of internal combustion engines. This paper describes an experimental verification of the “temperature swing” insulation concept, whereby the surface temperature of the combustion chamber wall follows that of the transient gas. First, we focus on the development of “temperature swing” insulation materials and structures with the thermo-physical properties of low thermal conductivity and low volumetric heat capacity. Heat flux measurements for the developed insulation coating show that a new insulation material formed from silica-reinforced porous anodized aluminum (SiRPA) offers both heat-rejecting properties and reliability in an internal combustion engine. Furthermore, a laser-induced phosphorescence technique was used to verify the temporal changes in the surface temperature of the developed insulation coating.
2016-04-05
Technical Paper
2016-01-0664
Ahmed E. Hassaneen, Wael I. A. Aly, Gamal Bedair, Mohammed Abdussalam
Abstract The thermal performance of an ammonia-water-hydrogen absorption refrigeration system using the waste exhaust gases of an internal combustion diesel engine as energy source was investigated experimentally. An automotive engine was tested in a bench test dynamometer, with the absorption refrigeration system adapted to the exhaust pipe via a heat exchanger. The engine was tested for different torques (15 N.m, 30 N.m, and 45 N.m). The exhaust gas flow to the heat exchanger built on the generator was controlled manually using two control valves. The refrigerator reached a steady state temperature between 10 and 14.5°C about 3.5 hours after system start up, depending on engine load. The maximum coefficient of performance was 0.10 obtained for the controlled exhaust mass flow case at torque 30 Nm after 3hrs from system startup.
2016-04-05
Journal Article
2016-01-0729
Takeshi Okamoto, Noboru Uchida
Abstract To overcome the trade-offs of thermal efficiency with energy loss and exhaust emissions typical of conventional diesel engines, a new diffusion-combustion-based concept with multiple fuel injectors has been developed. This engine employs neither low temperature combustion nor homogeneous charge compression ignition combustion. One injector was mounted vertically at the cylinder center like in a conventional direct injection diesel engine, and two additional injectors were slant-mounted at the piston cavity circumference. The sprays from the side injectors were directed along the swirl direction to prevent both spray interference and spray impingement on the cavity wall, while improving air utilization near the center of the cavity.
2016-04-05
Technical Paper
2016-01-0681
Cyrille Constensou, Vincent Collee
Abstract Increasing the efficiency of internal combustion engines is mandatory to meet ever more stringent regulations. The implementation of very high compression ratio (> 15:1) is the key to take full advantage of the association of Variable Compression Ratio (VCR) and Variable Valve Actuation (VVA) in the implementation of Miller-Atkinson cycle, leading to higher thermodynamic efficiency and thus better fuel consumption benefits. VVA systems allow differentiating geometric compression ratio and effective compression ratio. They theoretically permit to maximize expansion ratio (i.e. geometric compression ratio) while keeping an effective compression ratio in accordance with the constraints of the knocking limits, but with a limitation on the reachable maximum Brake Mean Effective Pressure (BMEP) at low compression ratio and the associated downsizing.
2016-04-05
Technical Paper
2016-01-1211
Hua Tian, WeiGuang Wang, Ge-Qun Shu, Xingyu Liang, Haiqiao Wei
Abstract Power lithium-ion battery is the core component of electric vehicles and hybrid electric vehicles (EVs and HEVs). Thermal management at different operating conditions affects the life, security and stability of lithium-ion battery pack. In this paper, a one-dimensional, multiscale, electrochemical-thermal coupled model was applied and perfected for a flat-plate-battery pack. The model is capable of predicting thermal and electrochemical behaviors of battery. To provide more guidance for the selection of thermal management, temperature evolutions and distributions in the battery pack at various ambient temperatures, discharge rates and thermal radiation coefficients were simulated based on six types of thermal management (adiabatic, natural convection, air cooling, liquid cooling, phase change material cooling, isothermal).
2016-04-05
Technical Paper
2016-01-1204
Dongchang Pan, Sichuan Xu, Chunjing Lin, Guofeng Chang
Abstract As one of the most crucial components in electric vehicles, power batteries generate abundant heat during charging and discharging processes. Thermal management system (TMS), which is designed to keep the battery cells within an optimum temperature range and to maintain an even temperature distribution from cell to cell, is vital for the high efficiency, long calendar life and reliable safety of these power batteries. With the desirable features of low system complexity, light weight, high energy efficiency and good battery thermal uniformity, thermal management using composite phase change materials (PCMs) has drawn great attention in the past fifteen years. In the hope of supplying helpful guidelines for the design of the PCM-based TMSs, this work begins with the summarization of the most commonly applied heat transfer enhancement methods (i.e., the use of thermally conductive particles, metal fin, expanded graphite matrix and metal foam) for PCMs by different researchers.
2016-04-05
Technical Paper
2016-01-1238
Paul Karoshi, Karin Tieber, Christopher Kneissl, Georg Peneder, Harald Kraus, Martin Hofstetter, Jurgen Fabian, Martin Ackerl
Abstract In hybrid electric vehicles (HEV), the operation strategy strongly influences the available system power, as well as local exhaust emissions. Predictive operation strategies rely on knowledge of future traction-force demands. This predicted information can be used to balance the battery’s state of charge or the engine’s thermal system in their legal operation limits and can reduce peak loads. Assuming the air and rolling drag-coefficient to be constant, the desired vehicle velocity, vehicle-mass and longitudinal driving resistances determine the vehicle’s traction-force demand. In this paper, a novel methodology, combining a history-based prediction algorithm for estimating future traction-force demands with the parameter identification of road grade angle and vehicle mass, is proposed. It is solely based on a route-history database and internal vehicle data, available on its on-board communication and measuring systems.
2016-04-05
Journal Article
2016-01-1239
Xueyu Zhang, Zoran Filipi
Abstract This paper develops a methodology to optimize the supervisory controller for a heavy-duty series hybrid electric vehicle, with consideration of battery aging and cooling loss. Electrochemistrybased battery aging model is integrated into vehicle model. The side reaction, reductive electrolyte decomposition, is modeled to determine battery aging rate, and the thermal effect on this reaction rate is considered by Arrhenius Law. The resulting capacity and power fading is included in the system-level study. Sensitivity analysis shows that battery aging could cause fuel economy loss by 5.9%, and increasing temperature could improve fuel economy at any given state-of-health, while accelerating battery aging. Stochastic dynamic programming algorithm is applied to a modeled system to handle the tradeoff between two objectives: maximizing fuel economy and minimizing battery aging.
2016-03-27
Technical Paper
2016-01-1732
Weicheng Huang
Abstract When the vehicle parks in direct sunlight conditions, the cabin will form a high-temperature thermal environment in hot weather. Drivers would turn on the air-conditioning with relatively high gear in the most conditions to reduce the cabin temperature, which could affect the life of equipment, resulting in energy waste and increasing emissions. This study adopted solar energy in the ventilation system. When the car parks the cabin blower was driven by a solar panel mounted on the car roof to discharge heat inside the cabin real time, achieving the purpose of pre-cooling. Firstly, heat transfer model and ventilation cooling model for the cabin were established according to the theory of heat transfer, and models were modified through experiments. Besides, the impact of ventilation flow rate on the pre-cooling effect was studied based on simulation analysis.
2016-03-25
WIP Standard
AIR5661A
This report provides data and general analysis methods for calculation of internal and external, pressurized and unpressurized airplane compartment pressures during rapid discharge of cabin pressure. References to the applicable current FAA and EASA rules and advisory material are provided. While rules and interpretations can be expected to evolve, numerous airplanes have been approved under current and past rules that will have a continuing need for analysis of production and field modifications, alterations and repairs. The data and basic principles provided by this report are adaptable to any compartment decompression analysis requirement.
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.
2016-03-19
Article
An "electronic assistant" with the capability to determine if the driver is capable of receiving information under safety critical conditions.
2016-03-16
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.
2016-03-16
WIP Standard
AS1046D
This standard is intended to apply to portable compressed gaseous oxygen equipment. When properly configured, this equipment is used either for the administration of supplemental oxygen, first aid oxygen or smoke protection to one or more occupants of either private or commercial transport aircraft.
2016-03-16
Standard
AS6296
This SAE Aerospace Standard (AS) specifies minimum performance standards for Electronic Flight Information System (EFIS) displays that are head-down and intended for use in the flight deck by the flight crew in all 14 CFR Part 23, 25, 27, and 29 aircraft. This document is expected to be used by multiple regulatory agencies as the basic requirement for a technical standard order for EFIS displays.
2016-03-14
Journal Article
2016-01-9107
Jan Christoph Menken, Martin Ricke, Thomas A. Weustenfeld, Juergen Koehler
Abstract Recent attempts to find energy-efficient thermal management systems for electric and plug-in hybrid electric vehicles have led to secondary loop systems as an alternative approach to meet dynamic heating and cooling demands and to reduce refrigerant charge. The choice of refrigerant for the primary refrigeration cycle is an important issue regarding the overall system performance. In this work, an HFC refrigerant (R-134a) and a natural refrigerant (R-744) are evaluated regarding a potential use in secondary loop systems. To meet the demands of R-744 cycles such as higher system pressure, most components have to be redeveloped. Nonetheless the use of the environmentally friendly refrigerant has advantages such as better applicability and performance in heat pump systems under cold ambient conditions.
2016-03-12
Article
Jeep Design is taking seven new concept vehicles, including two interesting pickups, to the Utah off-road festival where the hardest-core Jeep enthusiasts gather annually.
2016-03-11
Standard
J2810_201603
The purpose of this SAE Standard is to provide minimum performance and operating feature requirements for the recovery of HFC-134a (R-134a) refrigerant to be returned to a refrigerant reclamation facility that will process it to the appropriate AHRI 700 Standard or allow for on-site recycling of the recovered refrigerant to SAE J2788 specifications by using SAE J2788 or SAE J3030 -certified equipment. It is not acceptable that the refrigerant removed from a mobile air-conditioning (A/C) system with this equipment be directly returned to a mobile A/C system. An identifier certified to SAE J2912 is to be used to identify the contents of the system prior to recovery of the refrigerant.
2016-03-09
WIP Standard
ARP5021B
This document provides guidance for oxygen cylinder installation on commercial aircraft based on rules and methods practiced in aerospace industry and applicable in other associations. It covers considerations for oxygen systems from beginning of project phase up to production, maintenance, and servicing. The document is focused on requirements regarding DOT approved oxygen cylinders. However, its basic rules may also be applicable to new development pertaining to use of such equipment in an oxygen environment. For information regarding oxygen cylinders itself, reference should be made to AIR825/12 also.
2016-03-08
WIP Standard
AIR5742A
The scope of this document is related to the particular needs of oxygen equipment with regards to packaging and transportation. The document provides guidance for handling chemical, gaseous and liquid oxygen equipment. It summarizes national and international regulations to be taken into account for transportation on land, sea and air and provides information on classification of hazardous material. The aim of this document is to summarize information on packaging and transportation of oxygen equipment. Statements and references to regulations cited herein are for information only and should not be considered as interpretation of a law. Processes to maintain cleanliness of components and subassemblies during processing and assembly or storage of work-in-progress are outside the scope of this document.
2016-03-08
WIP Standard
AS916C
This SAE Aerospace Standard (AS) defines the overall requirements applicable to oxygen flow indicating devices intended to operate in conjunction with an oxygen regulator and mask system. Flow indicators covered by this document are for use with pressure demand, diluter-demand and continuous flow oxygen systems.
2016-03-05
Standard
AS8049/1A
This SAE Aerospace Standard (AS) defines Minimum Performance Standards (MPS), qualification requirements, and minimum documentation requirements for side-facing seats in civil rotorcraft, transport aircraft, and general aviation aircraft. The goal is to achieve comfort, durability, and occupant protection under normal operational loads and to define test and evaluation criteria to demonstrate occupant protection when a side-facing seat/occupant/restraint system is subjected to statically applied ultimate loads and to dynamic test conditions set forth in Title 14, Code of Federal Regulations (CFR) Part 23, 25, 27, or 29. While this document addresses system performance, responsibility for the seating system is divided between the seat supplier and the installation applicant. The seat supplier’s responsibility consists of meeting all the seat system performance requirements and obtaining and supplying to the installation applicant all the data prescribed by this document.
2016-03-03
Standard
J2683_201603
This SAE Standard applies to Carbon Dioxide R-744 refrigerant used to service motor vehicle passenger air-conditioning (A/C) systems designed to use CO2 (R-744). Hermetically sealed, refrigerated cargo systems are not covered by this document.
2016-03-03
Magazine
Multi-material structures move mpg upward The quest to improve fuel economy is not waning, nor is the desire to achieve higher mpg through the use of just the right lightweight material for the right vehicle application. Cars poised to become 'a thing' Making automobiles part of the Internet of Things brings both risks and rewards. Agility training for cars Chassis component suppliers refine vehicle dynamics at the high end and entry level with four-wheel steering and adaptive damping. SAE 2016 World Congress Preview Technology trends and exhibitor products are highlighted in this special section, which features Toyota's plans for the show floor, tech sessions, and more.
2016-03-02
Book
Mark Ahlers
The simultaneous operation of all systems generating, moving, or removing heat on an aircraft is simulated using integrated analysis which is called Integrated Energy System Analysis (IESA) for this book. Its purpose is to understand, optimize, and validate more efficient system architectures for removing or harvesting the increasing amounts of waste heat generated in commercial and military aircraft. In the commercial aircraft industry IESA is driven by the desire to minimize airplane operating costs associated with increased system weight, power consumption, drag, and lost revenue as cargo space is devoted to expanded cooling systems. In military aircraft thermal IESA is also considered to be a key enabler for the successful implementation of the next generation jet fighter weapons systems and countermeasures. This book contains a selection of papers relevant to aircraft thermal management IESA published by SAE International.
2016-03-02
Book
Mark Ahlers
Aircraft thermal management (ATM) is increasingly important to the design and operation of commercial and military aircraft due to rising heat loads from expanded electronic functionality, electric systems architectures, and the greater temperature sensitivity of composite materials compared to metallic structures. It also impacts engine fuel consumption associated with removing waste heat from an aircraft. More recently the advent of more electric architectures on aircraft, such as the Boeing 787, has led to increased interest in the development of more efficient ATM architectures by the commercial airplane manufacturers. The ten papers contained in this book describe aircraft thermal management system architectures designed to minimize airplane performance impacts which could be applied to commercial or military aircraft.
2016-03-02
Book
Mark Ahlers
This set is comprised of two titles, Aircraft Thermal Management: Systems Architectures and Aircraft Thermal Management: Integrated Energy Systems Analysis both edited by Mark Ahlers.
2016-02-29
Article
Ford begins its switch in April. GM expects most models to have R-1234yf by late 2016. And Mercedes is fitting an onboard fire-suppression system to allay engineers' fears of potential fire danger.
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