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2016-10-17
Technical Paper
2016-01-2160
Alexander Bech, Paul J. Shayler, Michael McGhee
The application of cylinder deactivation technology to small, three cylinder spark ignition engines has the potential to further improve the part load fuel economy of these downsized engines. Although the technology is well established and proven for larger multi-cylinder engines, this is not the case for the class of 1.0litre, three cylinder engines produced by several OEM’s for use in small cars. Deactivating one cylinder by leaving the intake and exhaust valves closed and cutting fuelling requires the other two cylinders to produce more work output to compensate. This changes the distribution of heat rejection to the engine structure. The resulting increases in temperature gradients within the engine structure, and transient response times for thermal adjustments following deactivation or reactivation are examples of the uncertainties which the work reported addresses.
2016-10-17
Technical Paper
2016-01-2161
Gangfeng Tan
Mg2Si1-xSnx thermoelectric material is eco-friendly and of high thermoelectric performance. In this research heat transfer and power generating characteristics of the automobile exhaust heat recovery system based on Mg2Si1-xSnx material were studied. Firstly, the heat transfer model for the exhaust heat recovery system was established. Then, based on primitive characteristics of Mg2Si1-xSnx material under the different Sn/Si ratio, two-phase heat transfer of coolant was adopted and the heat transfer process was analyzed. Finally, when the saturation temperature of coolant in the two-phase zone was respectively 373K and 343K, the heat transfer and power generating characteristic were analyzed for each condition.
2016-10-17
Technical Paper
2016-01-2262
Atsushi Shimada, Yuzo shirakawa, Takao Ishikawa
The internal combustion engine wastes large amount of heat energy. The heat energy accounts for about 60% of the fuel energy supplied to an engine. If the heat energy could be converted the output power of an engine, the thermal efficiency of an engine could be improved. On the other hand, the thermal efficiency of an engine has peaked because of the each combustion properties, such as knocking, narrow combustible range in spark ignition (SI) engine. The thermal efficiency of SI engine increases as the compression ratio and the ratio of the specific heat increase. If high octane number fuel is used for the fuel of the engine, the thermal efficiency could be improved. Moreover, if fuel can burn in dilute condition, the thermal efficiency could be improved further. Therefore, an exhaust heat recovery, a high compression combustion, a lean combustion are important methods for the thermal efficiency improvement. These three methods could be combined by using hydrous ethanol as fuel.
2016-10-17
Technical Paper
2016-01-2221
Joshua Kurtis Carroll, Mohammad Alzorgan, Corey Page, Abdel raouf Mayyas
Electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) are considered as a promising future solution for sustainable transportation. This is due to the reduction in energy consumption when compared to conventional internal combustion engine (ICE) based vehicles. EVs and PHEVs contain an Energy Storage Systems (ESS). This increases the complexity of the system but also provides additional margins and fields for optimization. One of the most important elements of these vehicles is the ESS. The electrochemistry nature of battery systems is inherently sensitive to the temperature shifts. The shifts are controlled by the thermal management system of the traction battery systems, for electric-drive vehicles, which directly affects the overall vehicle dynamics. These dynamics include performance, long-term durability and cost of the battery systems. Hence, thermal management becomes an essential element in the achievement to meet the demand for better performance.
2016-09-27
Technical Paper
2016-01-8085
Yanjun Ren, Gangfeng Tan, Kangping Ji, Li Zhou, Ruobing Zhan
The hydraulic retarder is an auxiliary braking device generally equipped on commercial vehicles. Its oil temperature changing will influence the brake performance of hydraulic retarder. The Organic Rankine Cycle (ORC) is a good means to recover exhausted heat. Moreover, it can cool oil and stably control oil temperature with the help of heat absorption related with evaporation. Comprehensively considering the power change characteristics of hydraulic retarder and the ORC heat recovery performance, the boundary conditions of ORC are determined in order to maintain the oil temperature stability. In addition, the changing rules about the flow rate of working medium and the condensing air volume are acquired. In this research, the heat-producing properties of hydraulic retarder under different conditions and the external circulating performance is firstly analyzed. According to the oil temperature impact on braking performance, the target range of temperature control is prescribed.
2016-09-27
Technical Paper
2016-01-8057
Michael Glensvig, Heimo Schreier, Mauro Tizianel, Helmut Theissl, Peter Krähenbühl, Fabio Cococcetta, Ivan Calaon
Waste Heat Recovery (WHR) systems based on the Organic Rankine Cycle (ORC) are in development in several sectors of the commercial vehicle industry for on-road and off-road applications. It is considered to be a viable technology to achieve future CO2 or fuel consumption legislation. This paper covers the results of more than 2 years of development covering simulation, layout, control development, safety, DVP, testbed testing, vehicle integration and on-road testing of a WHR system using ethanol as fluid and a piston expander into a Euro VI long haul Iveco Stralis vehicle. The main focus of this paper is the detailed description of the on-road vehicle testing combined with holistic vehicle simulation in parallel to precisely evaluate and optimize the WHR system for real life driving cycles.
2016-09-27
Technical Paper
2016-01-8071
Igor Gritsuk, Vladimir Volkov, Yurii Gutarevych, Vasyl Mateichyk, Valeriy Verbovskiy
The article discusses the use of the combined heating system with phase-transitional thermal accumulator. The peculiarity of the presented system is that it uses thermal energy of exhaust gas, coolant and motor oil, and emissions of internal combustion engine during its operation to accumulate the thermal energy. The results of experimental studies of the combined heating system are shown. The use of the combined heating system within phase-transitional thermal accumulators is compared with the use of standard systems for vehicle engine ZMZ-66-06 (8FS 9.2 / 8) of truck GAZ-66-11. In case of using a single thermal accumulator it allows to reduce the heating time up to 22.9-79.6% for a coolant and up to 25-80.8% for motor oil. A system and methods for pre-start and after-start heating of the vehicle engine in the investigated system are developed. The structure of a mathematical model to study the engine heating system in its various options is described.
2016-09-27
Technical Paper
2016-01-8121
Riccardo Bianchi, Addison Alexander, Andrea Vacca
Vibrations at the cabin or at the implements of construction machinery represents important drawbacks from the points of view of machine productivity, safety and operator comfort. Oscillations of these machines are particularly relevant due to the absence of shock absorbers, typical of many machines such as wheel loaders, and their use in uneven ground conditions. Several hydraulic solutions have been proposed in the past to reduce oscillations at both the cabin or at the machine boom. Particularly, cabin oscillations can be attenuated by properly counteracting the exciting oscillatory forces from the tires with motion of the boom. Many state of the art machine utilize a passive methods to implement this strategy. The present work introduces a novel active solution, based on the control of the boom actuator without involving modifications of the standard hydraulic system.
2016-09-27
Technical Paper
2016-01-8079
Zhiwei Zhang, Gangfeng Tan, Mengying Yang, Zhongjie Yang, Mengzuo Han
Abstract: Hydraulic retarder is an important auxiliary braking device. Because of its large braking torque in high speed, smooth braking, low noise, long service life and small size, it is widely used on modern vehicles. Transmission fluid of traditional hydraulic retarder is cooled by engine cooling system, which is a waste of vehicle energy to discharge the exhausted heat directly. On account of the working characteristics of hydraulic retarder, this study designs a set of waste heat recovery system based on Organic Rankine Cycle(ORC). Under the premise of ensuring stable performance of hydraulic retarder, waste heat energy in transmission fluid is recycled to supplement energy requirements for cooling system. First of all, the principle model of 100:1 is established for thermal power of D300 retarder. Then through theoretical calculations, components' structural parameters of ORC are determined.
2016-09-27
Journal Article
2016-01-8100
Jordan Kelleher, Nikhil Ajotikar
Piston cooling nozzles/jets play several crucial roles in the power cylinder of an internal combustion engine. Primarily, they help with the thermal management of the piston and provide lubrication to the cylinder liner and the piston’s wrist pin. In order to evaluate the oil jet characteristics from various piston cooling nozzle (PCN) designs, a quantitative and objective process was developed. The PCN characterization began with a computational fluid dynamics (CFD) turbulent model to analyze the mean oil velocity and flow distribution at the nozzle exit/tip. Subsequently, the PCN was tested on a rig for a given oil temperature and pressure. A high-speed camera captured images at 2500 frames per second to observe the evolution of the oil stream as a function of distance from the nozzle exit. An algorithm comprised of standard digital image processing techniques was created to calculate the oil jet width and density.
2016-09-20
Technical Paper
2016-01-2000
Mark Bodie, Thierry Pamphile, Jon Zumberge, Thomas Baudendistel, Michael Boyd
Abstract As technology for both military and civilian aviation systems mature into a new era, techniques to test and evaluate these systems have become of great interest. To achieve a general understanding as well as save time and cost, the use of computer modeling and simulation for component, subsystem or integrated system testing has become a central part of technology development programs. However, the evolving complexity of the systems being modeled leads to a tremendous increase in the complexity of the developed models. To gain confidence in these models there is a need to evaluate the risk in using those models for decision making. Statistical model validation techniques are used to assess the risk of using a given model in decision making exercises. In this paper, we formulate a transient model validation challenge problem for an air cycle machine (ACM) and present a hardware test bench used to generate experimental data relevant to the model.
2016-09-20
Technical Paper
2016-01-1978
Philippe Coni, Sylvain Hourlier, Xavier Servantie, Laurent Laluque, Aude Gueguen
Abstract A 3D Stereoscopic Head-Up Display (HUD) using direct projection on a transparent screen is presented. Symbol incrustation in conformity with the landscape is performed through the use of simulated collimation offering a large eye-box, in excess of conventional HUD. The use of spectral glasses for our transparent screen was decided as most commonly used polarizing or active glasses were not adapted. Furthermore it gave ususeful green laser attack protection.
2016-09-20
Technical Paper
2016-01-1994
Wei Wu, Yeong-Ren Lin, Louis Chow, Edmund Gyasi, John P. Kizito, Quinn Leland
Abstract For aircraft electromechanical actuator (EMA) cooling applications using forced air produced by axial fans, the main objective in fan design is to generate high static pressure head, high volumetric flow rate, and high efficiency over a wide operating range of rotational speed (1x∼3x) and ambient pressure (0.2∼1 atm). In this paper, a fan design based on a fan diameter of 86 mm, fan depth (thickness) of 25.4 mm, and hub diameter of 48 mm is presented. The blade setting angle and the chord lengths at the leading and trailing edges are varied in their suitable ranges to determine the optimal blade profiles. The fan static pressure head, volumetric flow rate, and flow velocity are calculated at various ambient pressures and rotational speeds. The optimal blade design in terms of maximum total-to-total pressure ratio and efficiency at the design point is obtained via CFD simulation.
2016-09-20
Journal Article
2016-01-1995
Patrick McCarthy, Nicholas Niedbalski, Kevin McCarthy, Eric Walters, Joshua Cory, Soumya Patnaik
Abstract As the cost and complexity of modern aircraft systems increases, emphasis has been placed on model-based design as a means for reducing development cost and optimizing performance. To facilitate this, an appropriate modeling environment is required that allows developers to rapidly explore a wider design space than can cost effectively be considered through hardware construction and testing. This wide design space can then yield solutions that are far more energy efficient than previous generation designs. In addition, non-intuitive cross-coupled subsystem behavior can also be explored to ensure integrated system stability prior to hardware fabrication and testing. In recent years, optimization of control strategies between coupled subsystems has necessitated the understanding of the integrated system dynamics.
2016-09-20
Technical Paper
2016-01-1997
Wei Wu, Yeong-Ren Lin, Louis Chow, Edmund Gyasi, John P. Kizito, Quinn Leland
Abstract The aircraft electromechanical actuator (EMA) cooling fan is a critical component because an EMA failure caused by overheating could lead to a catastrophic failure in aircraft. Fault tree analysis (FTA) is used to access the failure probability of EMA fans with the goal of improving their mean time to failure (MTTF) from ∼O(5×104) to ∼ O(2.5×109) hours without incurring heavy weight penalty and high cost. The dual-winding and dual-bearing approaches are analyzed and a contra rotating dual-fan design is proposed. Fan motors are assumed to be brushless direct current (BLDC) motors. To have a full understanding of fan reliability, all possible failure mechanisms and failure modes are taken into account.
2016-09-20
Technical Paper
2016-01-1999
Debabrata Pal, Frank Feng
Abstract In 3-phase AC application, there is additional heat dissipation due to skin effects and proximity effects in bus bars. In addition, when the 3- phase AC is used to drive a motor at high fundamental frequency, for example between 666 Hz and 1450 Hz, there are higher bus bar losses due to presence of higher frequency harmonic content. High frequency current carrying bus bars in aircraft power panels are typically cooled by natural convection and radiation. In this paper a thermal and electrical finite element analysis (FEA) is done for a bus bar system. For electrical loss modeling, 3D electromagnetic FEA is used to characterize losses in three parallel bus bars carrying AC at various frequencies. This loss analysis provides correlation of heat loss as function of frequency. A method is presented where this AC loss is incorporated using computational fluid dynamics (CFD) based thermal model.
2016-09-20
Journal Article
2016-01-2023
Timothy Deppen, Brian Raczkowski, Marco Amrhein, Jason Wells, Eric Walters, Mark Bodie, Soumya Patnaik
Abstract Future aircraft systems are projected to have order of magnitude greater power and thermal demands, along with tighter constraints on the performance of the power and thermal management subsystems. This trend has led to the need for a fully integrated design process where power and thermal systems, and their interactions, are considered simultaneously. To support this new design paradigm, a general framework for codifying and checking specifications and requirements is presented. This framework is domain independent and can be used to translate requirement language into a structured definition that can be quickly queried and applied to simulation and measurement data. It is constructed by generalizing a previously developed power quality analysis framework. The application of this framework is demonstrated through the translation of thermal specifications for airborne electrical equipment, into the SPecification And Requirement Evaluation (SPARE) Tool.
2016-09-20
Journal Article
2016-01-2054
Deniz Unlu, Federico Cappuzzo, Olivier Broca, Pierpaolo Borrelli
Abstract This paper presents the activities foreseen on the Leonardo Aircraft Division EIS (Entry In Service) 2020 derivative aircraft performed in the frame of the FP7 European research project TOICA (Thermal Overall Integrated Concept of Aircraft). On board air systems for conventional aircraft are fed by the bleed off-take which penalizes the amount of power available to the turbine of jet or turboprop engines. In order to minimize such operating penalties and optimize the energy efficiency of the overall aircraft, it is of major interest to support trade-offs at aircraft level including aircraft systems as early as possible in the development cycle. The study presents the Virtual Integrated Aircraft methodology and associated simulation activities relying on the system simulation platform LMS Imagine.Lab. This methodology is also relying on concept of flexible model and pyramid of models developed in the context of TOICA.
2016-09-20
Technical Paper
2016-01-1998
Michele Trancossi, Jose Pascoa, Carlos Xisto
Abstract Environmental and economic issues related to the aeronautic transport, with particular reference to the high-speed one are opening new perspectives to pulsejets and derived pulse detonation engines. Their importance relates to high thrust to weight ratio and low cost of manufacturing with very low energy efficiency. This papers presents a preliminary evaluation in the direction of a new family of pulsejets which can be coupled with both an air compression system which is currently in pre-patenting study and a more efficient and enduring valve systems with respect to today ones. This new pulsejet has bee specifically studied to reach three objectives: a better thermodynamic efficiency, a substantial reduction of vibrations by a multi-chamber cooled architecture, a much longer operative life by more affordable valves. Another objective of this research connects directly to the possibility of feeding the pulsejet with hydrogen.
2016-09-18
Technical Paper
2016-01-1935
Binyu Mei, Xuexun Guo, Gangfeng Tan, Ming Chen, Bo Huang, Longjie Xiao
With the continuous increasing requirements of commercial vehicle weight and speed on highway transportation, conventional friction brake is difficult to meet the braking performance. To ensure the driving safety of the vehicle in the hilly region, eddy current retarder has been widely used due to its fast response, lower prices and convenient installation. Electric eddy current retarder breaks the vehicle through the electromagnetic force generated by the current, and converted vehicle mechanical energy into heat through magnetic field. Air cooling structure is often used in the traditional eddy current retarder and cooling performance is limited, which causes low breaking torque, thermal recession, low reliability and so on. A water jacket has been equipped outside the eddy current region in this study, and the electric eddy current retarder is cooled through the water circulating in the circuit, which prolongs its working time.
2016-09-18
Technical Paper
2016-01-1941
Tie Wang, Gangfeng Tan, Xuexun Guo, Shengguang Xiong, Zhiwei Zhang, Xin Gao
Vehicle hydraulic retarder is applied in heavy-duty trucks and buses as an auxiliary braking device. In traditional cooling system of hydraulic retarder, working fluid is introduced into heat exchanger to transfer heat to cooling liquid in circulation, whose heat is then dissipated by engine cooling system, not enabling waste heat of working fluid used effectively. In hydraulic retarder cooling system based on Rankine cycle, organic working fluid transfers heat with hydraulic retarder working fluid in Rankine cycle, and then outputs power through expansion machine. It can both reduce heat load of engine cooling system, and enhance thermal stability of hydraulic retarder while recovering and utilizing braking energy. First of all, according to the target vehicle model, hydraulic retarder cooling system model based on Rankine cycle is established.
2016-09-18
Technical Paper
2016-01-1920
Deaglan O'Meachair, Stamatis Angelinas, Matthew Crumpton, Antonio Rubio Flores, Juan Garcia, Pablo Barles
Bentley Motors Ltd. has developed a Carbon Silicon Carbide (CSiC) brake system for it’s Mulsanne product, introduced at 17MY. The CSiC brake system is conceived as a performance brake system, and as such offers notable improvements in brake performance In developing the brake system, particular focus was placed on meeting the refinement levels required for a premium product, and indeed as the flagship model for Bentley Motors, NVH refinement of the brake system was of particular concern. This paper intends to discuss the technical performance of the brake system and review the NVH performance of the brakes. This paper will also demonstrate the effect of vehicle isolation on the cabin NVH, and ultimately the passenger experience, by comparing the noise and vibration content in the wheel arch with that apparent to the driver.
2016-09-18
Journal Article
2016-01-1929
Nimrod Kapas, Ajith Jayasundera
Abstract There is an increasing interest in transient thermal simulations of automotive brake systems. This paper presents a high-fidelity CFD tool for modeling complete braking cycles including both the deceleration and acceleration phases. During braking, this model applies the frictional heat at the interface on the contacting rotor and pad surfaces. Based on the conductive heat fluxes within the surrounding parts, the solver divides the frictional heat into energy fluxes entering the solid volumes of the rotor and the pad. The convective heat transfer between the surfaces of solid parts and the cooling airflow is simulated through conjugate heat transfer, and the discrete ordinates model captures the radiative heat exchange between solid surfaces. It is found that modeling the rotor rotation using the sliding mesh approach provides more realistic results than those obtained with the Multiple Reference Frames method.
2016-08-23
Standard
J2956_201608
This SAE Recommended Practice describes the test procedures for conducting side impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mounting testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.
2016-08-23
Standard
J2914_201608
This document provides an overview on how and why EGR coolers are utilized, defines commonly used nomenclature, discusses design issues and trade-offs, and identifies common failure modes. The reintroduction of exhaust gas into the combustion chamber is just one component of the emission control strategy for internal combustion (IC) engines, both diesel and gasoline, and is useful in reducing exhaust port emission of Nitrogen Oxides (NOx). Other means of reducing NOx exhaust port emissions are briefly mentioned, but beyond the scope of this document.
2016-08-19
Standard
AIR4170B
This document describes the initial development, evolution, and use of reticulated polyurethane foam as an explosion suppression material in fuel tanks and dry bays. It provides historical data, design practice guidelines, references, laboratory test data, and service data gained from past experience. The products discussed in this document may be referred to as "Safety Foam," "Reticulated Polyurethane Foam," "Baffle and Inerting Material," or "Electrostatic Suppression Material." These generic terms for the products discussed in this document are not meant to imply any safety warranty. Each individual design application should be thoroughly proof tested prior to production installation.
2016-08-19
Standard
AIR5354A
The following is the history of SAE Committee A-10.
2016-08-17
Standard
J3044_201608
This SAE Recommended Practice describes the test procedures for conducting rear impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mount testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.
2016-08-17
Standard
J2917_201608
This SAE Recommended Practice describes the test procedures for conducting frontal impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mounting testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.
2016-08-11
Standard
AIR1826A
This Aerospace Information Report (AIR) is limited in scope to the general consideration of environmental control system noise and its effect on occupant comfort. Additional information on the control of environmental control system noise may be found in 2.3 and in the documents referenced throughout the text. This document does not contain sufficient direction and detail to accomplish effective and complete acoustic designs.
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