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Viewing 1 to 30 of 19531
2016-10-17
Technical Paper
2016-01-2189
Bo WANG, Tawfik Badawy, Yanfei Li, Hongming Xu, Yizhou Jiang, Xinyu Zhang
Atomization of fuel sprays is a key factor in control of combustion quality in direct-injection engines. In this present work, effect of injection pressure and flash boiling levels of Ethanol (ETH) on near nozzle spray patterns was investigated using an ultra-high speed imaging technique. Ethanol was injected from a single-hole piezo injector into an optically accessible constant volume chamber at injection pressures of 30 MPa, 40 MPa and 50 MPa at different back pressure and temperature. High-speed imaging was performed using a long-distance microscope coupled with an ultra-high speed camera (Shimadzu HPV-2). The results revealed a clear mushroom-like structure at the start of injection at 30 MPa injection pressure and ambient condition whereas at higher injection pressure or higher flash boiling level this mushroom shaped injection tip was not observed. Micro cone angle experienced a sudden increase during the start of spray and then dropped.
2016-10-17
Technical Paper
2016-01-2202
Naoya Ochiai, Jun Ishimoto, Akira Arioka, Nobuhiko Yamaguchi, Yuzuru Sasaki, Nobuyuki Furukawa
The advanced development and optimization of fuel atomization in port and direct injection systems for automobile engine is desired for the improvement of fuel combustion performance and thermal efficiency of the engine. Computational prediction and design of injector nozzle spray flow is an effective method for that. However, a practical simulation method of the continuous primary, secondary spray breakups and the spraying behavior have not been developed yet. In this study, we have developed the integrated computational method of the total fuel atomization process of the injector nozzle. This new computational approach is taking into account the nozzle internal flow to form the primary breakup using Volume of Fluid (VOF) method in connection with the spray flow characteristics to the engine cylinder using Discrete Droplet Model (DDM).
2016-10-17
Technical Paper
2016-01-2272
Carl Bennett, Jason Bell, Jeffrey Guevremont
Elastomer compatibility is an important property of lubricants. When seals degrade oil leakages may occur, which is a cause of concern for original equipment manufacturers (OEMs) because of warranty claims. Leakage is also a concern for environmental reasons. Most often, the mechanical properties and fitting of the oil seals is identified as the source of failure, but there are cases where the interaction between the lubricant and the seal material can be implicated. The performance of seal materials in tensile testing is a required method that must be passed in order to qualify lubricant additive packages. We conducted an extensive study of the interactions between these elastomeric materials and lubricant additive components, and their behavior over time. The physicochemical mechanisms that occur to cause seal failures will be discussed.
2016-10-17
Technical Paper
2016-01-2345
Guoyu FENG, Wenku Shi, Henghai Zhang
To study the static and dynamic characteristics of thrust rod, based on multi-body dynamics and finite element method for static and dynamic characteristics of the thrust rod were analyzed. The establishment of a dynamic simulation model of vehicle and the road, in the extreme conditions of the thrust rod loads were calculated. Thrust rod finite element model is established, according to the calculation result of the load and test data of rubber, stiffness, strength and modal analysis, and verified by test, gained its deformation, stress distribution and low-order natural frequency and mode shape. The results provide a theoretical basis for the design and optimization of the thrust rod.
2016-10-17
Technical Paper
2016-01-2204
Takafumi Mori, Masanori Suemitsu, Nobuharu Umamori, Takehisa Sato, Satoshi Ogano, Kenji Ueno, Oji Kuno, Kotaro Hiraga, Kazuhiko Yuasa, Shinichiro Shibata, Shinichiro Ishikawa
One effective and easy way to improve fuel economy for automobiles is to decrease viscosity of lubricants, as it brings less churning loss. However, this option creates a higher potential for thinner oil film, which could damage the mechanical parts. This paper describes a new low-viscosity gear oil technology which was successfully developed to improve wear at tapered-roller bearings in differential gear units, whereas achieving higher fuel economy performance. As for tapered-roller bearings in differential gear units protected by gear oils, one major damage is supposed to cause wear at large end face of rollers and the counterpart, so-called bearing bottom wear. In order to understand the wear mechanism, wear at rolling contact surface of rollers and the counterparts, so-called bearing side wear was additionally observed to confirm the wear impact on tapered-roller bearing.
2016-09-27
Technical Paper
2016-01-2145
Ryan Haldimann
Inspection of fasteners prior to installation is critical to the quality of aerospace parts. Fasteners must be inspected for length/grip and diameter at a minimum. Inspecting the fasteners mechanically just prior to insertion can cause additional cycle time loss if inspection cannot be performed at the same time as other operations. To decrease fastener inspection times and to ensure fastener cartridges contain the expected fastener a system was devised to measure the fastener as it travels down the fastener feed tube. The optics system is designed such that two views 90° apart are captured of the fastener. The fastener is backlit using telecentric illuminators and imaged using a telecentric lens. The processing of the image occurs on the camera. The information as to what fastener the operator has loaded into the bowl is sent to the camera including the expected diameter and overall length.
2016-09-27
Technical Paper
2016-01-2084
Curtis Hayes
Successfully riveting aerospace fatigue-rated structure (for instance, wing panels) requires achieving rivet interference between a minimum and a maximum value in a number of locations along the shank of the rivet. In unbalanced structure, where the skin is much thicker than the stringer, this can be particularly challenging, as achieving minimum interference at D2 (the exit of the skin) can often be a problem without exceeding the maximum interference at D4 (exit of the stringer). Softer base materials and harder, higher-strength rivets can compound the problem. This paper presents a solution that has been successfully implemented on a production commercial aircraft. The application of a special coating on the tail side die dramatically reduces D4 interference, which in some instances resulted in a reduction of more than 30%. This allowed an increase in forming force to increase D2 interference and made for a much more robust process.
2016-09-27
Technical Paper
2016-01-2083
Steven P. Smith
This paper traces the development of a single sided blind fastener at Airbus’ Broughton’s plant, commencing with the initial identification of the need for the A380XWB programme, through various prototypes testing early production trials. These requirements were further refined for A350XWB, resulting in a new contending fastener design, further evaluation and testing before pre-production trials and selection for A350XWB programme. Experience gained has led to further design development by the supplier leading to its current applications which are explained and the next steps of our Journey.
2016-09-27
Technical Paper
2016-01-2079
Alexander Janssen, Thorsten Dillhoefer
The industry wide requirement of new highly flexible automated fastening systems in aircraft production has created the need for developing new fastening systems. This paper will focus on the development of the Frame Riveting Assembly Cell (FRAC) by BROETJE-Automation to meet this need. The new FRAC machine configuration is built for automated drilling and fastening of different aircraft type panels. It is highly flexible with a high speed positioning system mounted outer end effector. System travel is limited only by installed track length. The FRAC integrates well with conventional and reconfigurable automated fastening work holding tools.
2016-09-27
Technical Paper
2016-01-2098
Christophe Vandaele, Didier Friot, Simon Marry, Etienne Gueydon
With more than 10 000 aircrafts in their order backlog, automated assembly is of critical importance to the progress for aircraft manufacturers. Moreover to obtain maximum benefit from automation, it is necessary to achieve not only an integrated fastener cell, but also a real breakthrough in fasteners technology. The optimum solution, known as "One Side Assembly", performs the whole assembly sequence from one side of the structure using an accurate robot arm equipped with a Multi function End effector and high performances fasteners. This configuration provides an efficient and flexible automated installation process, superior to current solutions which are typically, large scale, capital intensive, systems, which still require operators to complete or control the fastener installation. The search for a technological breakthrough in this domain has been targeted for more than 15 years by the majors aircrafts manufacturers.
2016-09-27
Technical Paper
2016-01-2128
Henry Guo, Farid Ahdad, DeDong Xie
V-band joint is widely used in turbocharger industry. It is used to connect housings in turbocharger for both passenger vehicle and commercial vehicle applications, which can provide simple and robust solutions to replace bolt flanges. However, current issue for V-band joint in turbine side is the higher cost. The major cost for V-band joint comes from T-bolt which works in very hostile environment with high temperature and high vibration level. T-bolt is made from special stainless steel which takes around a half cost of total joint. This paper introduces a new V-band joint which replaces T-bolt from special bolt to standard bolt through changing bolt stress status from tension to compression, which provides possibility to reduce cost greatly. The prototype is made and performed static tests including anti-rotating torque test and salt spray test.
2016-09-27
Journal Article
2016-01-2080
Carter L. Boad, Kevin Brandenstein
The newest generation of automated fastening machines require a feed system that is smaller, more flexible, and faster than any currently available. The feed system must be compact enough to fit on a robot base, yet have a capacity large enough to support unmanned production for hours. A large variety of fasteners must be supported and the entire system must be reloaded or reconfigured in minutes to match the next work piece being assembled by the machine. When requested by the part program, the correct fastener must be released directly and immediately into the feed tube to minimize cycle time. This paper describes a new “plate cartridge” feed system developed to meet these needs.
2016-09-27
Journal Article
2016-01-2085
Kyle Pritz, Brent Etzel, Zheng Wei
The automation cycle time of wing assembly can be shortened by the automated installation of single-sided temporary fasteners to provide temporary part clamping and doweling during panel drilling. Feeding these fasteners poses problems due to their complexity in design and overall heavy weight. In the past, Electroimpact has remotely fed these fasteners by blowing them through pneumatic tubing. This technique has resulted in occasional damage to fasteners during delivery and a complex feed system that requires frequent maintenance. Due to these issues, Electroimpact has developed a new fully automated single-sided temporary fastening system for installation of the LISI Clampberry fasteners in wing panels for the C919 wing factory in Yanliang, China. The feed system stores fasteners in gravity-fed cartridges on the end effector near the point of installation.
2016-09-27
Journal Article
2016-01-2081
Rodrigo Pinheiro, Robert Gurrola, Sead Dzebo
The installation of common threaded aerospace fasteners by the application of a torque to a nut or collar is made possible by an internal wrenching element or recess feature adapted to the threaded end of a pin, which accepts a mating anti-rotation key designed to partially balance the applied torque. In applications such as the mechanical joining of composite structures accomplished by wet clearance fit installations of permanent fasteners, high nut or collar seating torques not adequately opposed by frictional resistance at the contact surfaces of the fastener and joint members effectively shift a greater proportion of the torque reaction requirement onto the recess and mating anti-rotation key which in turn can experience high torsional stresses exceeding their design capability and result in frequent service failures.
2016-09-27
Technical Paper
2016-01-2089
Jose Guerra cEng, Miguel Angel Castillo
During the year 2003 Aernnova decided to invest in automated machines procuring and installing a Broetje automatic machine (known in Aernnova as CIMPA) in Aernnova Berantevilla facility in order to perform operations such as drilling, countersinking or riveting in aircraft structures during its assembly. Due to the high load of work at that time in Aernnova mainly due to work packages from Embraer and Sikorsky, a solution was needed in order to assemble all the products required by our customer and deliver them on properly in terms of time and good quality. Several ideas came to our engineering team always having in mind the idea of reducing time being more competitive specially in repetitive operations and at the same time keeping good quality. Finally after a depth search, the option selected was an automated machine from Broetje that after some adjustments and customizations regarding our purposes could provide us the best solution.
2016-09-27
Technical Paper
2016-01-8062
Jham Kunwar Tikoliya, Ram Krishna Kumar Singh, Ramesh Kumar, Suresh Kumar Kandreegula
The existing head cover is having external oil and blow by separation unit, which is not only costlier but also complex and leads to increase the overall height of engine which was difficult to integrate in new variants of vehicles. Existing head cover sealing system was also not foolproof and with slight variation in part dimensions, there were high chances of leakage. A new head cover has been designed with internal baffle type oil and blow by separation system to ensure efficient separation and proper packaging of the system in new varients.The new system has been finalized after 26 DOEs of different wire mesh sizes and different baffle plate size and positions. The final system has two bowl shaped separation unit with wire mesh with two cup type oil separation passages and one baffle plate for separating blow by. The system works on condensation and gravity method. The blow by is guided through a well-defined passage integrated in aluminum cylinder head cover itself.
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
2016-01-2039
Prashant S. Vadgaonkar, Ullas Janardhan
Avionics industry is moving towards fly-by wire aircrafts with less reliance on mechanical systems leading to increase in the complexity of in-flight hardware elements. RTCA/DO-254 and EUROCAE ED-80 plays a vital role in the design assurance of airborne electronic hardware. RTCA/ DO-254 and EUROCAE ED-80 are the industry standards for Design Assurance Guidance for Airborne Electronic Hardware. The two different agencies FAA and EU regulate and apply this design assurance guidance to the regulatory law in CFR and EASA CS respectively. This paper discusses the need for DO-254 /ED-80 certification in Aerospace industry, the advantages and benefits to the avionics manufacturers. The paper presents the study made on similarities and differences between DO-254/ED-80.
2016-09-18
Technical Paper
2016-01-1960
Yukihisa Takayama
Vehicle production volumes have been increasing, particularly in newly developing countries that often lack adequate infrastructure. Rolling bearings for automotive wheels, Hub Unit Bearings, used in the developing markets, are required to prevent premature failures due to water ingress. These regions utilize many unimproved roads and frequently experience heavy rainfall, necessitating product features to enhance robustness against exposure to large amounts of contamination and water that may otherwise lead to damage of the Hub Unit Bearing rolling surfaces. Automotive bearings are also required to incorporate low friction technology to reduce overall fuel consumption. Growth in emerging markets tends to increase the amount of global carbon dioxide emissions and the use of low friction technologies in automotive bearings can help mitigate those increases.
2016-09-18
Technical Paper
2016-01-1957
Seonho Lee, Heejae Kang, Ohchul Kwon, Chirl Soo Shin
A trend in automotive parts development is the pursuit of long life, high quality and reliability. The increase in service life of automotive wheel bearings, by improving the rolling contact fatigue (RCF) life of bearing steels, was investigated. Conventional studies of bearing steels and heat treatments have dealt with quenching and tempering (Q/T) in 52100 steel. This study is a new trial to increase the strength of bearing steels by special austempering in phases after general Q/T heat treatments.
2016-09-18
Journal Article
2016-01-1956
Robert G. Sutherlin, Douglas Reed
Abstract For higher mileage vehicles, noise from contaminant ingress is one of the largest durability issues for wheel bearings. The mileage that wheel bearing sealing issues increase can vary due to multiple factors, such as the level of corrosion for the vehicle and the mating components around the wheel bearing. In general, sealing issues increase after 20,000 to 30,000 km. Protecting the seals from splash is a key step in extending bearing life. Benchmarking has shown a variety of different brake corner designs to protect the bearing from splash. This report examines the effect of factors from different designs, such as the radial gap between constant velocity joint (CVJ) slinger and the knuckle, knuckle labyrinth height and varying slinger designs to minimize the amount of splash to the bearing inboard seal. This report reviews some of the bearing seal failure modes caused by splash.
2016-09-18
Journal Article
2016-01-1958
Seungpyo Lee, Nahyon Lee, Jongkeun Lim, Jungyang Park
Abstract Through transmitting power and carrying vehicle weight, automotive wheel bearings play an important role. Counterbalancing the bearing responsibilities, they also are designed to last the life of a vehicle without servicing. When mounted to the vehicle steering knuckle by bolts, distortion occurs to the outer ring. Performance is affected when distortion takes place at the seal mounting location and raceways. Finite element analysis using commercial software was performed to analyze the outer ring distortion. Elasto-plastic and contact analyses were carried out to compute the clamping behavior of the outer ring, bolts and the knuckle under various conditions. To verify the reliability of this study, the distortion of the outer ring was measured. The experimental results proved to be comparative with the analysis results.
2016-09-18
Journal Article
2016-01-1959
Laura Sguotti, Davide Olivieri, Domenico Bosco
Abstract Bearing friction is a direct contribution to vehicle CO2 emissions. The friction is defined as the total resistance to rotation, resulting from the combination of rolling and sliding friction in the contact areas. First, friction reduction was approached from a theoretical standpoint by employing modeling and simulation techniques. Improvements identified in simulation were then used to: create a new set of design rules for the internal geometry of the bearing, introduce a new grease, develop new seals, also with the integration of labyrinth functions and an optimization of the preload range variation. In order to provide a reliable confirmation of the expected achievements, a new friction measurement methodology was also introduced.
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.
2016-08-19
Standard
AS90708A
SCOPE IS UNAVAILABLE.
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