Display:

Results

Viewing 271 to 300 of 10341
2015-09-29
Technical Paper
2015-01-2888
Devadatta Mukutmoni, Tristan Donley, Jaehoon Han, Karthik Mahadevan Muthuraman, P. David Campbell, Tom Mertz
Abstract Design and evaluation of construction equipments and vehicles in the construction industry constitute a very important but expensive and time consuming part of the engineering process on account of large number of variants of prototypes and low production volumes associated with each variant. In this article, we investigate an alternative approach to the hardware testing based design process by implementing a Computational Fluid Dynamics (CFD) simulation based methodology that has the potential to reduce the cost and time of the entire design process. The simulation results were compared with test data and good agreement was observed between test data and simulation.
2015-09-22
Article
Without idling the truck’s main engines, an auxiliary power unit can provide heating and cooling to maintain a comfortable temperature in the cab and sleeper, as well as power laptops, gaming machines, and microwaves. Fleets need to provide drivers with the ability to maintain their wanted comfort level on the road while also ensuring resources are being used wisely.
2015-09-22
WIP Standard
AIR6256
The aim of this document is to provide a comprehensive synopsis of regulations applicable to aircraft oxygen systems. The context of physiological requirements, international regulations, operational requirements and airworthiness standards is shown to understand the role of aircraft oxygen systems and to demonstrate under which circumstances is needed on aircraft. With regards to National Aviation Regulations States are committed to the Convention on International Aviation (Chicago Convention). The majority of states have adopted, with some deviations, FAA and EASA systems including operational and airworthiness requirements. Accordingly the extent of this document is primarily focused on FAA/EASA requirements.
2015-09-22
Technical Paper
2015-36-0301
Gonzalo Taboada
Abstract The proposed paper establishes a standard for load control of the air conditioning system and leak detection, for Trucks, Tractors, Harvester, Sprayers and Construction Machines. Also develop tests to measure the performance of air conditioning system in product audits. These processes are focused on mass production and not for repairs. The target, is establish an parameter objectively, for the comfort conditions offered by air conditioning systems, because the field claims, generally are subjective. All test and controls are designed for, ecologic fluid. R-134a In this paper, parameters are shown to directly control, the comfort provided by the air conditioning system of Agricultural Equipment, Construction and Industrial Vehicles, taking measurements of temperature inside the cabin and ambient conditions. Also, we have indirect parameters, for comparison with the internationally established comfort zones by ASHRAE organization for inside a cabin.
2015-09-22
Technical Paper
2015-36-0316
Marcelo Luiz Vieira Lóss, Luciana Pisati Jansen
Abstract Costumers today are discerning, savvy, style conscious and extremely well aware of latest design trends and quite naturally, are lot more demanding than any generation before then. The growth in the application of plastic replacing natural leather, fabrics, metallic and ceramic materials, in order to increase productivity and decrease production costs, has been demanding process development to improve quality and not only mirror the appearance of the original materials, with their texture and colors but also presenting new opportunities and alternatives. The Challenge in automotive interior Design for emerging markets are the choice of materials finish, execution and harmony to guarantee customer satisfaction considering that costumers are spending more time on interior vehicles than ever.
2015-09-22
Technical Paper
2015-36-0549
Wendler Augusto Zacariotto, Lorenzo Campos Coiado, Daniel Braga Barros, Lia Toledo Moreira Mota, Alexandre de Assis Mota
Abstract This work aims the implementation of a system able to estimate the occupancy rate (number of occupants) inside motor vehicles. This system is based on a Wireless Sensors Network using the standard IEEE 802.15.4, connected to a computer. The estimation of occupancy rate inside the motor vehicle can provide better energy efficiency and therefore optimize fuel and battery consumption.
2015-09-22
Technical Paper
2015-36-0333
Carlo Vezzá, Eider Moraes, Fernando Ooki
Abstract The acoustic comfort inside the vehicle justifies important attention during its development phase, because customers desire a quiet interior to have a more relaxing environment, easier to have conversations and to listen to the radio. Generally, acoustic insulators are distributed on vehicle body to minimize the portion of noise that enters the vehicle and, in the interior, absorber components are used to reduce the cabin noise reverberation. Internal noise absorption is mainly performed by headliners, carpets and seats. In order to contribute to the sound absorption inside the vehicle made through the seats and to propose a foam and fabric configuration that demonstrates the best acoustic performance, this work aims to compare combinations of three different foam densities with eight different fabrics using the Kundt´s tube.
2015-09-22
Technical Paper
2015-36-0409
Gabriel Kuntzer, Mario E. S. Martins, Fernando M. Bayer, Paulo A. Soliman, Marcello Sangaletti
Abstract The performance required by the actual spark ignition engines have increased the demands on the cooling system. In addition, in formula style competitions like Formula SAE the use of aerodynamics brought new problems about airflow restriction, requiring a complex study in the heat exchange area. The ideal cooling system in this case uses a heat exchanger that will maintain the engine on the optimum working temperature. To make this possible the paper presents a methods of evaluating heat exchangers and to predict the heat generated by the engine. In order to get the data needed for the analysis, some experimental measurements are made, the water pump flow rate are measured and temperature sensors are added to both, cold and hot, fluids. The air velocity profile through the radiator core showed to be a very important factor in this situation, trying to predict it, CFD simulations have been used.
2015-09-18
WIP Standard
J2395
This SAE Recommended Practice applies to both Original Equipment Manufacturer (OEM) and aftermarket ITS message-generating systems for passenger vehicles and heavy trucks. The recommended practice describes the method for prioritizing ITS in-vehicle messages and/or displayed information based on a defined set of criteria. Each criterion has a fixed number of levels that are used to rate/rank a given message or information item to determine its prioritization value. The prioritization value is used to determine the priority in which simultaneous, or overlapping, in-vehicle messages are presented to the driver.
2015-09-18
WIP Standard
ARP5526E
This SAE Aerospace Recommended Practice (ARP) documents a common understanding of terms, compliance issues and design criteria to facilitate certification of seat installations specific to Part 25 aircraft. This ARP provides general guidance for seats to be installed in Part 23 aircraft and Parts 27 and 29 rotorcraft and does not specify specific designs or design methods for such certification.
2015-09-17
WIP Standard
J3110
This SAE standard applies to any and all Flushing Methods intended for use to internally clean, decontaminate, and recondition components and sections of the refrigerant circuit within a vehicle air conditioning system. This standard provides testing and acceptance criteria for determining the minimum performance of a Flushing Method, intended for use in the servicing and repair process of vehicle air conditioning system. This standard will only specify the Flushing Method performance criteria. Specifications for air conditioning Flushing Fluids are outlined in SAE J3091.
2015-09-15
Technical Paper
2015-01-2415
Kyle Shimmin, Greg Russell, Robert A. Reuter, Steven Iden
Abstract A reduced order dynamic aircraft model has been created for the purpose of enabling constructive simulation studies involving integrated thermal management subsystems. Such studies are motivated by the increasing impact of on-board power and thermal subsystems to the overall performance and mission effectiveness of modern aircraft. Previous higher-order models that have been used for this purpose have the drawbacks of much higher development time, along with much higher execution times in the simulation studies. The new formulation allows for climbs, accelerations and turns without incurring computationally expensive stability considerations; a dynamic inversion control law provides tracking of user-specified mission data. To assess the trade-off of improved run-time performance against model capability, the reduced order formulation is compared to a traditional six degree-of-freedom model of the same air vehicle.
2015-09-15
Technical Paper
2015-01-2420
Henry A. Catherino
Abstract The heat generation rate of a lithium ion cell was estimated using a reversible heat generation rate equation. Because the equation is based on the energy conservation law, the influence of kinetically slow processes should be considered. In this analysis, the influence of kinetically slow processes is present but it is small within the domain of the test measurements. This approximation can be of significant usefulness for modeling the thermal response of single cells and multi-cell batteries.
2015-09-15
Technical Paper
2015-01-2419
Naoki Seki, Noriko Morioka, Hidefumi Saito, Hitoshi Oyori
Abstract This paper describes the concept of an air/fuel integrated thermal management system, which employs the VCS (Vapor Cycle System) for the refrigeration unit of the ECS (Environment Control System), while exchanging the heat between the VCS refrigerant and the fuel into the engine, and presents a feasibility study to apply the concept to the future all electric aircraft systems. The heat generated in an aircraft is transferred to the ECS heat exchanger by the recirculation of air and exhausted into the ram air. While some aircraft employ the fluid heat transfer loop, the transferred heat is exhausted into the ram air. The usage of ram air for the cooling will increase the ram drag and the fuel consumption, thus, less usage of ram air is preferable. Another source for heat rejection is the fuel. The heat exchange with the fuel does not worsen the fuel consumption, thus, the fuel is a preferable source.
2015-09-15
Technical Paper
2015-01-2561
Fernando Stancato, Sandro Conceicao, Ramon Papa, Luis Santos
Abstract Nowadays CFD analysis including virtual manikins is vastly applied to evaluate thermal comfort inside different working environments, such as buildings cars and aircrafts. Inside aircraft cabins, added to the numerical challenges due to geometrical complexity, the available subjective responses used to judge occupant local thermal comfort are usually based on buildings and cars experiments [1]. In the present paper however, it is applied an aircraft based subjective responses to evaluate thermal comfort which was specifically developed using regional jet mock-up experiments. The evaluation for the two approaches will be compared providing insight of the main differences.
2015-09-15
Technical Paper
2015-01-2582
Andre Silva, Nayeff Najjar, Shalabh Gupta, Paul D'Orlando, Rhonda Walthall
Abstract The Environmental Control System (ECS) of an aircraft provides thermal and pressure control of the engine bleed air for comfort of the crew members and passengers onboard. For safe and reliable operation of the ECS under complex operating environments, it is critical to detect and diagnose performance degradations in the system during early phases of fault evolution. One of the critical components of the ECS is the heat exchanger, which ensures proper cooling of the engine bleed air. This paper presents a wavelet-based fouling diagnosis approach for the heat exchanger.
2015-09-15
Technical Paper
2015-01-2418
Ricardo Gandolfi, Luiz Ribeiro, Jorge Oliveira, Kleber Paiva, Marcia Mantelli
Abstract Due to the increasing power density of onboard electric and electronic equipment and heat dissipation in civil and military aircraft, more efficient ways of transferring heat and new cooling techniques are necessary. A passive heat transfer prototype was developed and experimentally evaluated in laboratory and on ground and flight tests in an Embraer test aircraft. The passive heat transfer device consists of a loop-thermosyphon with two condensers and a common evaporator, using water as the heat transfer working fluid. An electric resistance and a variable power source were used to dissipate heat inside the evaporator simulating heat transfer from an onboard electronics bay. The fuselage/external air stream and the air flow inside an air conditioning system duct were used as heat sinks. Prior to flight test, laboratory tests were conducted simulating ground and flight operations.
2015-09-15
Journal Article
2015-01-2416
Charles E. Oberly, Michelle Bash, Benjamin R. Razidlo, Travis E. Michalak, Fernando Rodriguez
Abstract An IPTMS hardware facility has been established in the laboratories of the Aerospace Systems Directorate of the Air Force Research Laboratory (AFRL) at Wright-Paterson Air Force Base (WPAFB). This hardware capability was established to analyze the transient behavior of a high power Electrical Power System (EPS) coupled virtually to a Thermal Management System (TMS) under fast dynamic loading conditions. The system incorporates the use of dynamic electrical load, engine emulation, energy storage, and emulated thermal loads operated to investigate dynamics under step load conditions. Hardware architecture and control options for the IPTMS are discussed. This paper summarizes the IPTMS laboratory demonstration system, its capabilities, and preliminary test results.
2015-09-15
Journal Article
2015-01-2545
Reza Ahmadi, Oliver Marquardt, Marc Riedlinger, Reinhard Reichel
Abstract Aircraft cabin systems, especially cabin management systems (CMS) have to cope with frequent cabin changes during their lifecycle. This includes not only layout rearrangements and technological upgrades during the service, but also extensive CMS customizations and product variations before aircraft delivery. Therefore it is inevitable for the CMS to be highly changeable and offer an easy and agile change process. Today's CMS solutions face this challenge with configurable system architectures. Although such architectures offer a vast change domain, they usually come with time consuming and error prone change processes. This paper introduces an adaptive avionics software architecture that enables the CMS to cope with cabin changes highly automatically and with minimal human interactions. The adaptation is performed during an on ground organization phase, in which system changes are detected and evaluated by the CMS itself.
2015-09-15
Standard
J1994_201509
This SAE Recommended Practice is applicable to all heat exchangers used in vehicle and industrial cooling systems. This document outlines the tests to determine the heat transfer and pressure drop performance under specified conditions. This document has been reviewed and revised by adding several clarifying statements to Section 4.
2015-09-14
WIP Standard
AIR1168/10A
This AIR is arranged in the following two sections: 2E - thermodynamic characteristics of working fluids, which contains thermodynamic diagrams for a number of working fluids currently in use and supplied by various industrial firms; and 2F - properties of heat transfer fluids, which contains data, primarily in graphical form, on fluids that are frequently used in fluid heat transfer loops. Other properties of the environment, gases, liquids, and solids, can be found, as follows, in AIR 1168/9: 2A-Properties of the natural environment; 2B-Properties of gases; 2C-Properties of liquids and 2D- Properties of solids.
2015-09-06
Technical Paper
2015-24-2533
Mirko Bovo, Joop Somhorst
The focus on engine thermal management is rapidly increasing due to the significant effect of heat losses on fuel consumption, engine performance and emissions. This work presents a time resolved, high resolution 3D engine heat balance model, including all relevant components. Notably, the model calculates the conjugated heat transfer between the solid engine components, the coolant and the oil. Both coolant and oil circuits are simultaneously resolved with a CFD solver in the same finite volume model as the entire engine solid parts. The model includes external convection and radiation. The necessary boundary conditions of the thermodynamic cycle (gas side) are mapped from a calibrated 1D gas exchange model of the same engine. The boundary conditions for the coolant and at the oil circuits are estimated with 1D models of the systems. The model is calibrated and verified with measurement data from the same engine as modeled.
2015-09-06
Journal Article
2015-24-2443
Jesus Benajes, Jaime Martin, Antonio Garcia, David Villalta, Alok Warey, Vicent Domenech, Alberto Vassallo
In the last two decades engine research has been mainly focused on reducing pollutant emissions. This fact together with growing awareness about the impacts of climate change are leading to an increase in the importance of thermal efficiency over other criteria in the design of internal combustion engines (ICE). In this framework, the heat transfer to the combustion chamber walls can be considered as one of the main sources of indicated efficiency diminution. In particular, in modern direct-injection diesel engines, the radiation emission from soot particles can constitute a significant component of the efficiency losses. Thus, the main of objective of the current research was to evaluate the amount of energy lost to soot radiation relative to the input fuel chemical energy during the combustion event under several representative engine loads and speeds. Moreover, the current research characterized the impact of different engine operating conditions on radiation heat transfer.
2015-09-06
Journal Article
2015-24-2536
Julien Bouilly, Francois Lafossas, Ali Mohammadi, Roger Van Wissen
Abstract In the automotive field, reducing harmful pollutant, CO2 emissions and fuel consumption of vehicles while increasing customer comfort is a continuous challenge that requires more and more sophisticated technology implementations. However, it is often difficult to anticipate the advantages and drawbacks of a technology without having its prototype parts and/or knowing the optimal control strategy. In order to meet these challenges, the authors have developed a vehicle thermal model in AMESim platform to evaluate the benefits of an Active Grille Shutter (AGS) on fuel economy when applied. The vehicle model was based on a C-Segment vehicle powered by a 1.4L Diesel engine. The complete oil and coolant circuits were modeled as well as a friction model based on engine coolant and oil temperature.
2015-09-03
WIP Standard
J3109
To define a test standard for the measurement of efficiency and a usage-weighted evaluation for the purpose of reporting to EPA for emissions credits.
2015-09-01
Technical Paper
2015-01-1814
Tatsuya Kuboyama, Shunsuke Goto, Yasuo Moriyoshi, Keiichi Koseki, Yoichi Akiyama
In this study, the effect of the low octane number fuel on HCCI engine performance was experimentally investigated using a slightly modified commercial four-cylinder gasoline engine. To operate the engine in HCCI strategy with wide operational range, the blowdwon supercharging (BDSC) system proposed by the authors was applied in the test engine. Research octane number (RON) of test fuels was varied from 90 to 78.5 as an experimental parameter. Experimental results showed that in the range of the present study, HCCI operational range, brake thermal efficiency and exhaust emissions during HCCI operation were little affected by the RON of the test fuels. In contrast, during SI operation, thermal efficiency was deteriorated with lower RON fuel because of knocking.
2015-09-01
Technical Paper
2015-01-1832
Hideaki Osada, Noboru Uchida, Yoshio Zama
Impingement of a spray flame on the periphery of the piston cavity strongly affects heat loss to the wall. The heat release rate history is also closely correlated with the indicated thermal efficiency. For further thermal efficiency improvement, it is thus necessary to understand such phenomena in state of the art diesel engines, by observation of the actual behavior of an impinging spray flame and measurement of the local temperature and flow velocity. A top-view optically accessible engine system, for which flame impingement to the cavity wall can be observed from the top (vertically), was equipped with a high speed digital camera for direct observation. Once the flame impinged on the wall, flame tip temperature decreased roughly 100K, compared to the temperature before impingement.
2015-09-01
Technical Paper
2015-01-1868
Yukihide Nagano, Toshiaki Kitagawa, Atsushi Ohta, Shiro Takakura, Yutaka Tajima, Nobu Takahashi
EGR (Exhaust gas recirculation) can reduce the pumping loss and improve the thermal efficiency of spark ignition engines. The techniques for combustion enhancement under high EGR rate condition has been required for further improvement of the thermal efficiency. In order to develop the technique of combustion enhancement by turbulence, the influences of turbulence scale on combustion properties, such as probability of flame propagation, EGR limit of flame propagation, flame quenching and combustion duration were investigated under the condition of same turbulence intensity. Experiments were carried out for stoichiometric spherically propagating turbulent i-C8H18/Air/N2 flames using a constant volume vessel. It was clarified that all of these combustion properties were affected by the turbulence scale. The development of spherically propagating turbulent flame during flame propagation was affected by the turbulence scale.
2015-09-01
Technical Paper
2015-01-1883
Sejun Lee, Norimasa Iida, Takahiro Sako
This study tried to find a potential of dedicated EGR (d-EGR) system added to the four-cylinder spark ignition (SI) engine to decrease heat loss (Qheatloss) and improve thermal efficiency (ηth). Test fuels were chosen by methane and propane. PREMIX code in CHEMKIN-PRO was employed to calculate laminar burning velocity (SL) and flame temperature (Tf). Wiebe function and Wocshni's heat transfer coefficient were considered to calculate ηth. The results show that the d-EGR system increased ηth and it was higher than that of stoichiometric combustion of conventional SI engines due to the low Tf and fast SL.
2015-09-01
Technical Paper
2015-01-1884
Hisashi Miyai, Kyosuke Iwaya, Akira Kikusato, Jin Kusaka, Yasuhiro Daisho, Hisaharu Nakashima, Yoichi Kawaguchi, Daisuke Mizuguchi, Hiroyuki Hasegawa
Natural gas is a promising alternative fuel for internal combustion engines because of its clean combustion characteristics and abundant reserves. However, it has several disadvantages due to its low energy density and low thermal efficiency at low loads. Thus, to assist efforts to improve the thermal efficiency of spark-ignited (SI) engines operating on natural gas and to minimize test procedures, a numerical simulation model was developed to predict and optimize the performance of a turbocharged test engine, considering flame propagation, occurrence of knock and ignition timing. The numerical results correlate well with empirical data, and show that increasing compression ratios and retarding the intake valve closing (IVC) timing relative to selected baseline conditions could effectively improve thermal efficiency. In addition, employing moderate EGR ratios is also effective for avoiding knock.
Viewing 271 to 300 of 10341

Filter