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Viewing 1 to 30 of 15549
2015-09-29
Technical Paper
2015-01-2862
Hans Cuijpers, Mangesh Thorat
Introducing a new type of cold clamping as an application for mounting a bracket to a frame. This cold metal deformation process is recently introduced by KPIT & DAF Engineering (for DAF- Trucks, a Commercial Vehicle Manufacturer from the PACCAR GROUP} The current engineering of tubular mounting brackets has improved the product characteristics by eliminating critical welding process and introducing the new simple and robust cold clamping technology. This design model enables lower life-cycle cost consistent product with required performance, reliability & quality. Use of this bracket has lot of advantages over conventional welding process like simplified manufacturing process with an improved manufacturing tolerances. It eliminate the cost on sheet metal flattening and re-straightening metal tubes, improved Design for Assembly (DFA), easy to mount on vehicle without using any special tools and minimal assembly tolerances of the complete end assembly (less deviation).
2015-09-29
Technical Paper
2015-01-2791
Srinivas Anantharaman, Manoj Baskaran
Nozzles tip Temperature (NTT) of an injector is a critical parameter for an engine as far as reliability of engine is concerned. It is required to ensure that the injectors operate under its operational limit because higher operating temperatures would result in enlargement of the nozzle spray tip, resulting in higher through flow, producing more undesirable power. This could result in failure of other components in the engine. In this paper we identify the various parameters that are critical for NTT and thereby predict the NTT by having the known input parameters. Response surface methodology and artificial neural network are used to identify the parameters, estimate the significance of each parameter and predict the NTT. Based on this analysis, even without the use of an instrumented injector NTT can be predicted at various working conditions of the vehicle on different terrains.
2015-09-15
Technical Paper
2015-01-2453
Danilo Andreoli, Mario Cassaro, Manuela Battipede, Goodarz Ahmadi, Piergiovanni Marzocca
The control of the flow over aerodynamic shapes in order to achieve performance enhancements, such as improved aircraft maneuverability, has been a lively area of research for last two decades. Active flow control can produce significant performance improvement when combined in a closed-loop control system. Synthetic jet actuators (SJAs) are devices able to interact actively with the flow around a hosting structure by providing ejection and suction of fluid from an orifice. The research presented in this paper concerns the implementation of zero-net-mass-flux SJAs airflow control system on a NACA0015, low aspect ratio (LAR) wing section prototype developed by Clarkson University under the Advancement of Intelligent Aerospace Systems (AIAS) AFOSR Grant FA9550-09-1-0051. Two arrays of custom made SJAs, installed in the proximity of the leading edge and flap of the wing section, make up the actuation system.
2015-09-15
Technical Paper
2015-01-2468
Rebecca Margetts, Chris Bingham, Tim Smith
The ACHEON (Aerial Coanda High Efficiency Orienting-jet Nozzle) is a new alternative to tilting rotors and jet vectoring mechanical oriented nozzles and has enormous advantages because it is free of moving elements and potentially highly effective for Vertical Short-Take-Off and Landing (V/STOL) aircraft. A suitable control methodology is needed to effectively integrate surface controls with the TVC systems to allow the remote control of UAV’s. NDI is a proven control technique for unmanned aircraft with conventional flight control surfaces. This paper describes an implementation of an NDI controller in Matlab SIMULINK designed to be used for a range of aircraft models and practical implementations. In the paper the controller is successfully applied to a predefined UAV model where the performance of conventional systems can be compared to the advantages of TVC such as ACHEON.
2015-09-15
Technical Paper
2015-01-2607
Matthias Meyer
STAXX Compact 1700 is a new machining centre, designed for the production of carbon fibre parts, using the fibre placement process. It produces prepreg carbon fibre stacks near to net shape which need to be moulded. As today’s high volume production lacks a reliable production system that can handle carbon fibre with high efficiency and minimal material scrap, fibre placement is the only technology that reduces material scrap during the production process significantly, especially for shell shaped parts. Most of the technical applications for lightweight construction, such as in the automotive and aerospace industries are ‘shell’ type shaped parts. While textile production methods like in resin transfer moulding may cause a scrap rate of more than 50%, fibre placement would offer a total scrap rate of below 5%. Accordingly, fibre placement offers the design option to produce parts of variable wall thickness and local reinforcement.
2015-09-15
Technical Paper
2015-01-2600
Gustavo Franco Barbosa, Elton Candia Cordeiro, Fábio Rodrigues Costa
This paper presents a full automated solution that uses robots for manufacturing business jets primary parts. The purpose of this technological innovation is to increase productivity, improve the quality of final product, reduction of costs with maintenance and consumable materials, in addition to meet the requirements of ergonomics, occupational health and safety. So, it has been sought better results in terms of process efficiency and technological innovation faced to competitive market requirements related to industrial automation. The aim is to improve the manufacturing processes of the furniture parts, striving for excellence in every step by further adding value and reducing wastes in order to reduce manufacturing costs and enable greater customer satisfaction.
2015-09-15
Technical Paper
2015-01-2512
Mark W. Sydenham, Tim Brown
In numerous applications where access to the backside of the work piece is restricted, aircraft manufactures opt to install blind fasteners like the OSI-Bolt. However, one issue with using blind fasteners is that they can require visual inspection to verify proper installation. Electroimpact has developed an automated solution for installing OSI-Bolts which increases process reliability and decreases cost by eliminating the need for visual inspection. This solution utilizes Electroimpact’s existing accurate robotic system together with new hardware designed specifically for OSI-Bolts. In addition to automated drilling and fastener installation, this system performs numerous quality checks to insure the installed fastener meets engineering requirements. Before installing the fastener, the system measures actual stack thickness and the length of the fastener to ensure that the proper grip is installed.
2015-09-15
Technical Paper
2015-01-2464
Anna Suñol Jiménez, Tao Yang, Dean Vucinic
Thrust vectoring is of significant interest in the aeronautical field due to a higher manoeuvrability if compared to classical control surfaces, as well as improving aircraft’s performance for take-off, landing and flight, and avoiding the drag increase due to extending the aircraft’s control surfaces. Moreover, it enables Short/Vertical Take-Off and Landing (S/VTOL). In this context, an attempt to design a radically new concept of thrust vectoring nozzle based on fluidic elements is in current development. This novel nozzle, called ACHEON (Aerial Coanda High Efficiency Orienting-jet Nozzle), is designed to provide directional control without the movement of mechanical parts, taking advantage of the geometry of the nozzle to divert the jet to the desired direction due to the Coanda effect. Its simple mechanism bases the jet deviation control on the interaction of two primarily jets of different velocities, where the one with higher velocity entrains the one with lower velocity.
2015-09-15
Technical Paper
2015-01-2497
George Nicholas Bullen
Abstract The introduction of composite materials onto air vehicles has complicated the traditional hole/countersink assessment criteria due its finished-part thickness variability; softer and dissimilar properties than the metallic substructure where it is mounted and attached; and the increased attention to other acceptance criteria such as fiber tear, fiber pull, and moisture propagation in the hole that degrades fastener capability. The addition of composite materials further complicates the assembly process by adding a boundary layer of liquid shim or sealant between the composite piece (usually a skin) and the substructure. Current hole inspection systems are absent the ability to assess the interior condition of the composite hole such as fiber tear, damage to the liquid shim, and debris or burrs between the multiple stacks of dissimilar material.
2015-09-15
Journal Article
2015-01-2416
Charles E. Oberly, Michelle Bash, Benjamin R. Razidlo, Travis E. Michalak, Fernando Rodriguez
An IPTMS hardware facility has been established in the laboratories of the Aerospace Systems Directorate of the Air Force Research Laboratory at Wright-Paterson Air Force Base. This hardware capability was established to assess the integration issues and analyze the transient behavior of a high power Electrical Power System (EPS) couple virtually to a Thermal Management System (TMS). 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.
2015-09-15
Journal Article
2015-01-2491
Paul Haworth, Donald Peterson, Curtis Hayes
A new high speed forming process for fatigue rated index head rivets used in wing panel assembly using ball-screw based servo squeeze actuation has been developed. The new process is achieved using a combination of force and position control and is capable of forming to 40,000 lbs at rates of up to 200,000 lbs/second whilst holding the part location to within +/- 10 thousandths of an inch. Multi-axis riveting machines often have positioning axes that are also used for fastener upset. It is often the case that while a CNC is used for positioning control, another secondary controller is used to perform the fastener upset. In the new process, it has been possible to wrap the control of the upset process into the machine CNC and thus eliminating any separate controllers. The fastener upset force profile is controlled throughout the forming of the rivet by using a closed loop force control system that has a load cell mounted directly behind the stringer side forming tool.
2015-09-06
Technical Paper
2015-24-2467
Alessandro Ferrari, Federica Paolicelli
Abstract A challenging task that is required to modern injection systems is represented by the enhanced control of the injected quantities, especially when small injections are considered, such as, pilot and main shots in the context of multiple injections. The propagation of the pressure waves triggered by the nozzle opening and closure events through the high-pressure hydraulic circuit can influence and alter the performance of the injection apparatus. For this reason, an investigation of the injection system fluid dynamics in the frequency domain has been proposed. A complete lumped parameter model of the high-pressure hydraulic circuit has been applied to perform a modal analysis. The visualization of the main vibration modes of the apparatus allows a detailed and deep comprehension of the system dynamics. Furthermore, the possible resonances, which are induced by the action of the external forcing terms, have been identified.
2015-09-06
Technical Paper
2015-24-2470
Daniel Pearce, Yannis Hardalupas, A.M.K.P Taylor
The measurement of the rate of fuel injection using a constant volume, fluid filled chamber and measuring the pressure change as a function of time due to the injected fluid (the so called “Zeuch” method) is an industry standard due to its simple theoretical underpinnings. Such a measurement device is useful to determine key timing and quantity parameters for injection system improvements to meet the evolving requirements of emissions, power and economy. This study aims to further the understanding of the nature of cavitation which could occur in the near nozzle region under these specific conditions of liquid into liquid injection using high pressure diesel injectors for heavy duty engines. The motivation for this work is to better understand the temporal signature of the pressure signals that arise in a typical injection cycle.
2015-09-06
Journal Article
2015-24-2472
Nikolaos Papadopoulos, Pavlos Aleiferis
The design of a Diesel injector is a key factor in achieving higher engine efficiency. The injector's fuel atomisation characteristics are also critical for minimising toxic emissions such as unburnt Hydrocarbons (HC). However, when developing injection systems, the small dimensions of the nozzle render optical experimental investigations very challenging under realistic engine conditions. Therefore, Computational Fluid Dynamics (CFD) can be used instead. For the present work, transient, Volume Of Fluid (VOF), multiphase simulations of the flow inside and immediately downstream of a real-size multi-hole nozzle were performed, during and after the injection event with a small air chamber coupled to the injector downstream of the nozzle exit. A Reynolds Averaged Navier-Stokes (RANS) approach was used to account for turbulence. Grid dependency studies were performed with 200k-1.5M cells.
2015-09-06
Journal Article
2015-24-2462
Fabio Auriemma, Heiki Tiikoja
The acoustic impedance exhibited by a new type of element for noise control, the Micro-Grooved Elements (MGEs), has been widely investigated in this paper. The MGEs are typically composed of two overlying layers presenting macroscopic slots and a number of micro-grooves on one of the contact surfaces. The micro-grooves result in micro-channels as the layers are assembled to form the element. Similarly to Micro-Perforated Elements (MPEs), the MGEs have been proved to provide effective dissipation of acoustic energy by the means of viscous losses taking place in the micro-channels. However, in contrast to the MPEs, the MGEs use the grooves, instead of the holes, in which the air is forced to pass through. It results in more cost effective elements, which have been found to represent an adequate alternative for fibrous materials, typically present in silencer units.
2015-07-30
Standard
AIR1273B
This SAE Aerospace Information Report (AIR) establishes a positive identification of the functions and, if applicable, the hazards and direction of flow of pipe, hose, tube, or electrical conduit lines.
2015-07-28
Standard
AS172236D
SCOPE IS UNAVAILABLE.
2015-07-28
Standard
AMS6433G
This specification covers an aircraft-quality, low-alloy steel in the form of sheet, strip, and plate.
2015-07-28
Standard
MA3423A
SCOPE IS UNAVAILABLE.
2015-07-28
Standard
AMS4931E
This specification covers a titanium alloy in the form of bars 6.000 inches (152.40 mm) and under in nominal diameter or least distance between parallel sides, forgings and flash welded rings 6.000 inches (152.40 mm) and under in thickness, and stock for forging and stock for flash welded rings of any size.
2015-07-28
Standard
AMS6935B
This specification covers a titanium alloy in the form of bars up through 4.000 inches (101.60 mm) in nominal diameter or least distance between parallel sides, inclusive, forgings of thickness up through 4.000 inches (101.60 mm), inclusive, with bars and forgings having a maximum cross-sectional area of 32 square inches (204.46 cm2), and stock for forging of any size (See 8.7).
2015-07-28
Standard
AMS5656F
This specification covers a corrosion-resistant steel in the form of bars, wire, forgings, extrusions, flash welded rings, and stock for forging, extruding, or flash welded rings.
2015-07-27
Standard
AMSR83412/1A
The purpose of this specification sheet is to set up a standardized part numbering system for o-rings procured to MIL-R-83412(USAF), type 1.
Viewing 1 to 30 of 15549

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