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2017-10-08
Technical Paper
2017-01-2357
Mark Devlin, Jeffrey Guevremont, Chip Hewette, Marc Ingram, Grant Pollard, William Wyatt
Different mechanical components in a vehicle can be made from different types of steel and can even contain different steel alloys or coatings. Lubricant technology is needed to prevent wear and control friction on all of these different surfaces. Phosphorus compounds are the key additives that are used to control wear and they do this by forming tribofilms on surfaces. It has been shown that different operating conditions (pressures and loads) can influence the formation of tribofilms formed by different anti-wear additives. The effect of surface metallurgy and morphology on tribofilm formation is described in this paper. Our results show that additive technology can form proper tribofilms on various surfaces and the right combination of additives can be found for current and future surfaces.
2017-10-08
Technical Paper
2017-01-2366
Wenzheng Xia, Yi Zheng, Xiaokun He, Dongxia Yang, Huifang Shao, Joesph Remias, Joseph Roos, Yinhui Wang
Because of the increased use of gasoline direct engine (GDI) in automobile industry, there is a significant need to control particulates from GDI engines based on emission regulations. One potential technical approach is the utilization of a gasoline particulate filter (GPF). The successful adoption of this emission control technology needs to take many aspects into consideration and requires a system approach for optimization. This study conducted research to investigate the impact of vehicle driving cycles, fuel properties, catalyst coating on the performance of GPF. It was found that driving cycle has significant impact on particulate emission. Fuel quality still plays a role in particulate emissions, and can affect the GPF performance. Catalyzed GPF is preferred for soot regeneration, especially for the case that the vehicle operation is dominated by congested city driving condition, i.e. low operating temperatures. The details of the study are presented in the paper.
2017-10-08
Technical Paper
2017-01-2222
ZhenYang Liu, Xihui Wang
The ever increasing popularity of electric vehicles and demand in passengers comfort and safe requirements of vehicle have led more efficient heat pump air conditioning system to an indispensable device in electric vehicle. Many studies have shown that the addition of nano particles contributes to improving the thermal conductivity of nano fluids more than that of conventional refrigerants. Therefore, the appliance of the magnetic nano-refrigerant in heat pump air conditioning system has great potential to improve the heat transfer efficiency. This paper aims at studying the magnetic nano-refrigerant comprised of the magnetic nano powder Fe3O4 and refrigerant R134a.According to the relevant theoretical analysis and different empirical formula, the heat transfer coefficient, density, viscosity, and other physical parameters are calculated approximately.
2017-10-08
Technical Paper
2017-01-2183
Xiangfeng Yu, Shengcheng Li, Zhishuang Ma, Wei Du, Fengxiang Huang, Weijun Huang, Beiping Jiang
A reciprocating piston expander model based on organic Rankine cycle (ORC) is built for engine waste heat recovery. The expander characterizes by variable expansion ratio through adjusting refrigerant injection timing. This paper investigates the effect of refrigerant evaporating pressure, expansion ratio and clearance volume on the expander performance which mainly includes output power, expander efficiency, equivalent recovery efficiency, total output power, expander efficiency, weighted efficiency of expender and weighted heat recovery efficiency of expender. The results demonstrate that the total output power and the equivalent heat recovery efficiency increase with refrigerant evaporating pressure under overall operating conditions, while the increment is negligible. The expander reaches maximum total output power up to 83.442kW under c100 engine condition and 1.1MPa refrigerant evaporating pressure within the research operating conditions.
2017-10-08
Technical Paper
2017-01-2406
Wu Yang, Xiuting Yin, Zhang Song Zhan, Huixian Shen, Huibin Qing, Qingqiang Zeng, Liyun Kang
This work addresses the problem of fatigue strength prediction of crankshaft fillet rolling processes, to reduce friction losses, weights and material costs. It is usually assumed that the effect of fillet rolling process on crankshaft fatigue are conservative and empirically. A predicting method of fatigue strength for ductile cast iron crankshafts is presented, in which the rolling process is considered. The method including two parts: modelling of crankshaft fillet rolling dynamic and predicting fatigue strength of rolling process. The rolling process is solved with an implicit arithmetic and validated by the measurements and tests. Based on the crankshaft dynamic loads calculated by AVL/EXCITE Power Uint, the fatigue effect factors are considered, consisting of compressive residual stresses, work hardening, and reduction of the roughness. The predicting method is applied on a 1.5l I4 gasoline engine.
2017-10-08
Journal Article
2017-01-2343
Nicolas Champagne, Nicolas Obrecht, Arup Gangopadhyay, Rob Zdrodowski, Z Liu
The oil and additive industry is challenged to meet future automotive legislations aimed at reducing worlwide CO2 emissions levels. The most efficient solution used to date has been to decrease oil viscosity leading to the introduction of new SAE grades such as SAE 0W-8. However this solution may soon reach its limit due to potential issues related to wear with lower engine oil viscosities. In this paper, an innovative solution is proposed that combines the use of a new tailor-made polyalkylene glycol with specific anti-wear additives. Valvetrain wear measurements using radionuclide technique demonstrates the robustness of this solution. The wear performance was also confirmed in normalized GF-5 testings. An extensive tribological evaluation (film formation, wear testing and tribofilm surface analysis) of the interactions between the base oil and the anti-wear additives lead us to propose an underlying mechanism that can explain this performance benefit.
2017-09-19
Technical Paper
2017-01-2029
Thibaut BILLARD, Cedric Abadie, Bouazza Taghia
The present paper reports non-electrically intrusive partial discharge investigations on aeronautic and electric vehicle motors fed by SiC inverter drive under variable environmental conditions. A representative test procedure and experimental set-up based on operating aeronautic conditions are essential to ensure the accuracy and reliability of partial discharge test on aircraft systems to make informed decisions on insulation system design choice. The aim of this paper is to demonstrate the feasibility of partial discharge test of the insulation system on a different type of motor under such conditions, both electrically and environmentally. To do so, the paper will start by detailing the innovative experimental set-up to be used in the study. It mainly consists in a high-voltage (1000V) inverter drive using SiC components to provide fast rise time surges.
2017-09-19
Technical Paper
2017-01-2053
Jim Stabile
Since oxygen has been a part of the aircraft system it has always been managed using a difficult metric to understand.......PSI. Today's technology has allowed us to efficiently and inexpensively convert PSI into a timed based metric which allows for improved oxygen management and a method which provides an interface between two important energy aircraft resources (fuel and oxygen). These resources have inverse consumption rates tied directly to the altitude of the aircraft. Using time as the management metric, the pilot can balance these 2 resources during any oxygen contingency by varying the altitude of the aircraft.. This allows for regulatory fuel savings and an increase in operational safety This program diverges from traditional thinking in that it applies an information and skill based solution to a system that has otherwise been viewed as a hardware problem.
2017-09-19
Technical Paper
2017-01-2151
Hong huang, Qingyun Zhao, Fenglei Liu, Huadong Liu
Abstract:Split-sleeve cold expansion processing was employed on the 2024-T3 aluminum alloy plate. Fatigue lives were compared according different expansion, then the relationship of fatigue life and expansion was analyzed. Residual stresses were measured with different expension,and the fatigue fractograph was analyzed by SEM. The results show that the split-sleeve cold expansion can obtain longer life compared with the non strengthened hole. The maximum fatigue life increased to 12 times with 6% expansion. When over 6% expansion, fatigue life began to decrease. The split-sleeve cold expansion can form beneficial rasidual compressive stress,and deferred the fatigue crack initiation. The fatigue fractograph shows mixed transgranular fracture.
2017-09-19
Technical Paper
2017-01-2148
Ho-Sung Lee
This study presents some of current works in manufacturing launcher structural components with solid state welding and superplastic forming technology. The adoption of superplastic characteristics into manufacturing process makes many of aerospace components lighter and stiffer, since aerospace vehicle requires lightweight structures to obtain weight saving for increasing payloads and fuel efficiency. Some of titanium alloys, aluminum alloys and super alloys are typical examples of superplastic materials that have been used to produce complex shapes of aerospace components. The optimum strain rate sensitivity and strain rate range were obtained from biaxial bulging test and this parameters were used to manufacture the components with superplastic blow forming using hydrostatic gas pressure difference.
2017-09-19
Technical Paper
2017-01-2149
Cameron S. Gillespie
As carbon fiber reinforced plastics (CFRP) become integrated more and more into the design of aircraft structures, aircraft manufacturers are demanding higher speed and efficiency CFRP deposition systems. To facilitate the manufacture of large surface area and low contour parts (wing skins, in this case) at a high production rate, Electroimpact has developed a new Automated Fiber Placement (AFP) end effector consisting of twenty 1.5” wide pre-preg carbon tows. The new head design has been named the ‘OH20’, short for ‘One and a Half Inch, 20 Tows’. This AFP head format creates a deposition swath over 30 inches wide when all 20 tows are active. Two of these AFP end effectors have been integrated with a quick change robotic tool changer on a high speed, high acceleration, and accurate moving beam gantry. All end effector loading, maintenance, and cleaning can be accomplished in a maintenance cell while the other AFP head is in use depositing CFRP in the part cell.
2017-09-19
Journal Article
2017-01-2152
Sean Taklimi, Ali Ghazinezami, Kim Cluff PhD, Davood Askari
The use of nanomaterials and nanostructures have been revolutionizing the advancements of science and technology in various engineering and medical fields. As an example, Carbon Nanotubes (CNTs) have been extensively used for the improvement of mechanical, thermal, electrical, magnetic, and deteriorative properties of traditional composite materials for applications in high-performance structures. The exceptional materials properties of CNTs (i.e., mechanical, magnetic, thermal, and electrical) have introduced them as promising candidate for reinforcement of traditional composites. Most structural configurations of CNTs provide similar material properties; however, their geometrical shapes can deliver different features and characteristics. As one of the unique geometrical configurations, helical CNTs have a great potential for improvement of mechanical, thermal, and electrical properties of polymeric resin composites.
2017-09-19
Technical Paper
2017-01-2123
Violet Leavers
The need to maintain aircraft in remote, harsh environments poses significant challenges for on-site condition monitoring. For example, in desert assignments or on-board ships, frequent rotation of staff with variable levels of skill requires condition monitoring equipment that is not only robust and portable but also user friendly and requiring a minimum of training to set up and use correctly. The mainstays of any on-site aerospace maintenance program are various fluid and particulate condition monitoring tests that convey information about the current mechanical state of the system. In the front line of these is the collection and analysis of wear debris particles retrieved from a component’s lubricating or power transmission fluid or from magnetic plugs. It is standard practice within the specialist laboratory environment to view and image wear debris using a microscope.
2017-09-19
Technical Paper
2017-01-2124
Violet Leavers
Within the aviation industry the analysis of wear debris particles recovered from magnetic plugs and lubricating fluids is an essential condition monitoring tool. However, in large organisations, high staff turnover in remote work environments often leaves dangerous gaps in on-site support and background knowledge. The current work seeks to bridge those gaps by developing interactive software dedicated to wear debris particle classification, root cause diagnosis and serviceability prognostics. During the research several hundred wear debris particle images were collected, analysed and classified. Each image was analyzed by a number of experts and at each stage of the analysis the experts were questioned about the knowledge and experience used to make their diagnoses and prognoses. The end result is the compilation of an extensive knowledge base representing the combined expertise of a number of highly trained engineers, each with decades of hands-on experience.
2017-09-19
Technical Paper
2017-01-2050
Piotr Synaszko, Michal Salacinski, Patryk Ciezak
The work concerns the selection of measurement parameters for selected non destructive testing methods of Mi helicopter rotor blades after repair. Considered repair cases involve metal cracks in the sandwich skin and repair damage of honeycomb structure structure (puncture, dent). In the event of a crack, repair is performed by applying a composite-metal repair package. In case of damage of the core, its broken piece is replaced by a new one and then applied the same metal-composite package as in the case of crack repair. The present work focuses on detecting disbond between skin and core below repair patch and cracks under the repair package. Detecting cracks and assessing their length is important because the repair technology provides the repair package without removing of cracked part of skin. Authors have used laser shearography and C-scan methods for MIA and ET.
2017-09-19
Journal Article
2017-01-2153
Patrick Land, Petros Stavroulakis, Richard Crossley, Patrick Bointon, Harvey Brookes, Jon Wright, Svetan Ratchev, David Branson
Inspection of Composite panels is vital to the assessment of their ability to be fit for purpose. Conventional methods such as X-ray CT and Ultrasonic scanning can be used, however, these are often expensive and time consuming processes. In this paper we investigate the use of off the shelf NDT equipment utilizing Fringe projection and open source software to rapidly evaluate a series of composite panels. These results are then verified using destructive analysis of the panels to prove the reliability of the rapid NDT methods for use with evaluating carbon composite panels. This process allows us to rapidly identify regions of geometric intolerance or formed defects without the use of expensive sub-surface scanning systems, enabling a fast and cost effective initial part evaluation system. The focus of this testing series is on 6mm thick pre-preg carbon-epoxy composite laminates that have been laid up using (AFP) and formed using Thermal Roll Forming (TRF).
2017-09-19
Journal Article
2017-01-2142
Brandon Mahoney, Jamie Marshall, Thomas Black, Dennis Moxley
It is well recognized that weight savings within an airframe can result in significant lifetime cost savings and increased flight range. The transition of aluminum alloys to lighter, composite materials is an increasingly prevalent strategy to reduce weight on aircraft. This paper describes the application of a lightweight carbon fiber composite technology to aviation, engine start lithium batteries. The transition of lithium battery chassis technology from metal to composite introduces technical challenges not found with traditional battery chassis. Modern lithium batteries contain more than energy cells; common internal components include switch mode battery chargers, health and safety monitoring electronics, and even environmental control circuitry such as heaters. Consequently, electromagnetic interference disruption potential created by the electronics must be addressed.
2017-09-19
Journal Article
2017-01-2154
Alan Hiken
A review of critical technologies and manufacturing advances that have enabled the evolution of the composite fuselage is described. The author’s perspective on several development, military, and production programs that have influenced and affected the current state of commercial fuselage production is presented. The enabling technologies and current approaches being used for wide body aircraft fuselage fabrication and the potential reasons why are addressed. Some questions about the future of composite fuselage are posed based on the lessons learned from today and yesterday.
2017-09-19
Technical Paper
2017-01-2077
John McClelland, Michael Morgan, Caroline McClory, Colm Higgins, Rory Collins, Adrian Murphy, Yan Jin
The need to drill several million holes per aircraft through composite and hybrid material stacks is a large challenge for the aerospace assembly process. The ability to produce high quality holes for the lowest tooling costs is at the forefront of requirements for aircraft assembly factories worldwide. Consequently, much research has been conducted into tool design and development, however, the effect of drilling platform characteristics has not been well covered in literature. Respectively, this research has compared the drilling abilities of a 5-axis precision CNC platform, a hybrid parallel kinematic machine and an articulated robotic arm fitted with a drilling module. In-process force measurement and post process hole and tool analysis methods were used to better understand the effect of static and dynamic platform characteristics on the achievable hole quality, cycle time and tool wear when drilling aerospace metal alloy stacks.
2017-09-19
Technical Paper
2017-01-2087
Peter Mueller-Hummel, Alex Hjorten
This article characterizes the special features of machining composites in comparison to machining metal. Simplified theoretic models will demonstrate how CFRP should be machined without delamination, burn marks and cutting tool breakages. Different strategies can be chosen depending on the material removal rate. The paper will present, based on this analytical approach, how a drill should be designed in order to avoid the entrance, inner and exit delamination. While entrance and exit delamination is well understood, the paper will focus more to the delamination inside the bore. The appearance and the avoidance of the so called "Volcano Effect" and the reason why holes in composite becomes smaller after a couple of days will be explained. The comparison between 4 different cutting tool technologies will prove and give a better understanding how to use this theoretical approach.
2017-09-17
Technical Paper
2017-01-2495
Andrew M. Visser, Scott Severnak
California and Washington recently passed legislation to limit certain constituents in brake friction materials. As part of the California (CA) legislation brake friction brake pad manufacturers need to perform an alternative assessment to identify potentially safer environmental and toxicological choices for friction material production. Copper, chromium, lead, and other compounds have been identified as particularly harmful to the environment. This paper contains the methodology behind an objective and comprehensive alternative assessment to quantify the ecological impact of friction materials. Utilizing raw material specific Chemical Abstracts Service (CAS) numbers and their associated acute toxicology values, this method estimates the total toxicological impact of finished friction materials in an attempt to allow the manufacturer to screen greener alternatives.
2017-09-17
Technical Paper
2017-01-2507
Matthias Hoch, Michal Kaczmarek, Markus Ahr
The demand for zinc nickel coatings continuously increases in the automotive industry due to their high corrosion protection as well as superior wear and heat resistance compared to pure zinc platings. The state-of-the-art plating systems in the brake caliper industry are acid zinc nickel electrolytes, as only they allow for direct plating on cast iron. Cast iron is the most common base material for the production of automotive brake components due to excellent mechanical and thermal properties. Well suited coatings will preserve the functional properties and provide additional advantages like improved corrosion protection and homogenous and long lasting appearance. Consistently increasing quality demands, extended warranty periods and cost pressure lead to further developments and force the industry to look for new solutions.
2017-09-17
Technical Paper
2017-01-2528
Seongjoo Lee, JeSung Jeon, JooSeong Jeong, Byeongkyu Park, ShinWook Kim, ShinWan Kim, Seong Kwan Rhee, Wan Gyu Lee, Young sun Cho
It is widely believed or speculated that higher pad compressibility leads to reduced brake squeal and that caliper design can affect brake squeal. After encountering anecdotalcontradictory cases, this investigation was undertaken to systematically generate basic data and clarify the beliefs or speculations. In order to adjust pad compressibility, it is common to modify molding temperatures, pressures and times, which in addition to changing the compressibility, changes the coefficient of friction at the same time. In order to separate these two effects, NAO disc pads were prepared under the same molding conditions while using different thicknesses for the underlayer to achieve different compressibilities, thus changing compressibility without changing thecoefficient of friction. Test results show brake squeal increasing with increasing compressibility, contrary to the common belief.
2017-09-17
Journal Article
2017-01-2480
Roberto Dante, Andrea Sliepcevich, Marco Andreoni, Mario Cotilli
Tin sulfides (SnS, Sn2S3, and SnS2, represent a safer and greener alternative to other metal sulfides such as copper sulfides, etc. Their behavior is usually associated to that of solid lubricants such as graphite. A mixture of tin sulfides, with Sn having different oxidation states, has been characterized by scanning electron microscopy and by thermal gravimetric analysis (TGA). In order to investigate the effect of tin sulfides upon two crucial friction material ingredients, two mixtures were prepared: the former was made by mixing tin sulfides with graphite and the latter was made mixing tin sulfides with a straight novolak. They were analyzed by TGA and differential thermal analysis (DTA) in nitrogen air. Almost no interference was detected between tin sulfides and graphite in air since the thermal oxidation of the tin sulfides and that of graphite were separated by more than 200°C.
2017-09-17
Journal Article
2017-01-2481
Vishal Mahale, Jayashree Bijwe, Sujeet Sinha
Potassium titanate (KT) fibers/whiskers are used as a functional filler for partial replacement of asbestos in NAO friction materials (FMs). Based on little information reported in open literature; its exact role is not well defined since some papers claim it as the booster for resistance to fade (FR), or wear (WR) and sometimes as damper for friction fluctuations. Interestingly, KT fibers and whiskers (but not powder) are proved as carcinogens by the International Agency for Research on Cancer (IARC). However, hardly any efforts are reported on exploration of influence of KT powder and its optimum amount in NAO FMs (realistic composites) in the literature. Hence a series of five realistic multi-ingredient compositions in the form of brake-pads with similar parent composition but varying in the content of KT powder from 0 to 15 wt% (in the steps of 3) were developed. These composites were characterized for physical, mechanical, chemical and tribological performance.
2017-09-17
Journal Article
2017-01-2482
Meechai Sriwiboon, Nipon Tiempan, Kritsana Kaewlob, Seong K Rhee, Donald Yuhas
Disc pad physical properties are believed to be important in controlling brake friction, wear and squeal. Thus these properties are carefully measured during and after manufacturing for quality assurance. For a given formulation, disc pad porosity is reported to affect friction, wear and squeal. This investigation was undertaken to find out how porosity changes affect pad natural frequency, dynamic modulus, hardness and compressibility for a low-copper formulation and a copper-free formulation, both without underlayer. Pad natural frequency, modulus and hardness all decrease with increasing porosity. When pad compressibility is measured by compressing several times as recommended and practiced, the pad surface hardness is found to increase while pad natural frequency and modulus remain essentially unchanged. However, there is no consistent pattern in compressibility change with increasing porosity, and thus a question arises on the validity of compressibility measurement.
2017-09-17
Technical Paper
2017-01-2503
Binyu Mei, Xuexun Guo, Bo Yang, Shengguang Xiong, Gangfeng Tan
In order to ensure driving safety, heavy vehicles are often equipped with hydraulic retarder, which provides sustained and stable braking torque and converts the kinetic energy of the vehicle into heat taken away by the cooling system when the vehicle on a long downhill journey. The braking torque of conventional hydraulic retarder is modulated by adjusting the liquid filling rate, which leads to slow response and difficult control. In this paper, a new kind of magnetorheological (MR) fluid hydraulic retarder is designed by replacing the traditional transmission oil with MR fluid and arranging the excitation coils outside the working impellers. The braking torque can be controlled by the fluid viscosity of MR fluid with the variation of magnetic field. Compared with the traditional hydraulic retarder, the system has the advantages of fast response, easy control and high adjustment sensitivity.
2017-09-17
Technical Paper
2017-01-2510
Shengguang Xiong, Gangfeng Tan, Bo Yang, Longjie Xiao, Yongbing Xu, Yishi Wang
Fluid auxiliary braking devices can provide braking torque through hydraulic damping and fluid auxiliary braking devices can also convert the vehicular inertia energy into transmission fluid heat energy during braking, which can effectively alleviate the work pressure of the main brake. Traditional hydraulic auxiliary braking devices use transmission fluid to transmit torque , however, there is a certain lag effect during the braking. The magnetorheological fluid(MR fluid) can also be used to transmit torque because it has the advantages of controlling braking torque linearly and responding fast of the magnetic field changed. The temperature of the MR fluid will increase when the vehicle with continuous braking. The changes in MR fluid temperature will cause a bad influence on the efficiency stability of the auxiliary braking.
2017-09-17
Journal Article
2017-01-2523
Seonho Lee, Yoongil Choi, Kyuntaek Cho, Hyounsoo Park
Raceway groove is one of the main factors of causable wheel noise on driving. Many OEM customers have asked continuously its improvement and even they are demanding to verify for proactive control at bearing companies. Generally, the raceway groove of wheel unit is consequence of metallic yielding from external load in exposed unspecific environment. It means stronger yielding strength of steel can leading to resist from brinell occurrence. Both outer ring and hub based on the Gen.3 wheel unit are manufactured using by 1055 bearing quality steel (BQS) and harden them as the case hardening like induction hardening (IH). This paper presents the originality development steel and its IH design that are targeted long life bearing and brinell resistance improving on raceway developed by ILJIN AMRC (Advanced Materials Research Center).
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