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2015-06-15
Technical Paper
2015-01-2111
Marie-Laure Toulouse, Richard Lewis
Abstract The intent of this paper is to provide a general overview of the main engineering and test activities conducted in order to support A350XWB Ice and Rain Protection Systems certification. Several means of compliance have been used to demonstrate compliance with applicable Certification Basis (CS 25 at Amendment 8 + CS 25.795 at Amendment 9, FAR 25 up to Amendment 129) and Environmental protection requirements. The EASA Type Certificate for the A350XWB was received the 30th September 2014 after 7 years of development and verification that the design performs as required, with five A350XWB test aircraft accumulating more than 2600 flight test hours and over 600 flights. The flight tests were performed in dry air and measured natural icing conditions to demonstrate the performance of all ice and rain protection systems and to support the compliance demonstration with CS 25.1419 and CS25.21g.
2015-06-15
Technical Paper
2015-01-2130
Melissa Bravin, J. Walter Strapp, Jeanne Mason
Abstract In the last several years, the aviation industry has improved its understanding of jet engine events related to the ingestion of ice crystal particles. Ice crystal icing has caused powerloss and compressor damage events (henceforth referred to as “engine events”) during flights of large transport aircraft, commuter aircraft and business jets. A database has been created at Boeing to aid in analysis and study of these engine events. This paper will examine trends in the engine event database to better understand the weather which is associated with events. The event database will be evaluated for a number of criteria, such as the global location of the event, at what time of day the event occurred, in what season the event occurred, and whether there were local meteorological influences at play. A large proportion of the engine events occur in tropical convection over the ocean.
2015-06-15
Technical Paper
2015-01-2134
Tom Currie, Dan Fuleki
Abstract Ice crystals ingested by a jet engine at high altitude can partially melt and then accrete within the forward stages of the compressor, potentially causing performance loss, damage and/or flameout. Recent research into this ice crystal icing (ICI) phenomenon conducted at the National Research Council of Canada suggests that the liquid water content vliq of an accretion significantly affects the accretion's susceptibility to erosion by ice crystals, and therefore accretion growth. This paper describes the development and application of an instrument for measuring vliq, potentially providing a method for correlating erosion behavior (e.g. as ductile or brittle) and properties. The instrument measures the complex admittance Y* of a mixed-phase deposit bridging a pair of electrodes, which is modeled as a resistor and capacitor in parallel, and calculates the deposit's relative permittivity εr from the capacitance.
2015-06-15
Technical Paper
2015-01-2128
Enrico Bellussi
Abstract This paper describes the AgustaWestland (AW) experience in the use of the results obtained with the HISS flight tests to support the civil ice clearance for rotorcraft. The use of the HISS, a US Army CH-47D Chinook fitted with a spray bar system providing a cloud where the helicopter can fly in icing conditions, allows stable and prolonged flight data, conditions extremely difficult to encounter during natural ice flights. The paper analyses the definition of the HISS test matrix, to optimize the points needed for system development and the points possibly usable during certification, in both normal and failure mode conditions. It is also shown how the HISS ice campaigns results can be assessed, and how they can be compared to the natural ice flights to validate them. Finally it is explained how the HISS results can be used, in addition to natural ice flights results, to support the certification.
2015-06-15
Technical Paper
2015-01-2125
Dan Fuleki, Jennifer L.Y. Chalmers, Brian Galeote
This paper describes the equipment, analysis methods and results obtained for particle size measurements based on a particle imaging velocimetry (PIV) system in which a short duration laser pulse is used to backlight airborne particles. This produces high quality and high resolution images of fast moving airborne particles in a non-intrusive manner. This imaging technique is also used to examine particle morphology and 2D particle trajectory and velocity. The image analysis methods are outlined and validation test results discussed which show the measurement of reference glass beads between 20 and 400 microns were generally to within their stated size. As well, validation testing using known icing wind tunnel droplet distributions were compared with Spraytek 2000 Malvern droplet size measurements and showed agreement of the MVD's to be within ±5% for distributions having nominally 20, 40 and 80 micron MVD's.
2015-06-15
Technical Paper
2015-01-2147
Sandra Turner, Jean-Marc Gaubert, Remy Gallois, Thibault Dacla, Ingrid Mullie, Aurelien Bourdon, Fabien Dezitter, Alice Grandin, Alain Protat, Rodney Potts, Alfons Schwarzenboeck, J. Walter Strapp
Abstract The PLANET System was used for real-time satellite data transmission during the HAIC-HIWC Darwin field campaign (January to March 2014). The basic system was initially providing aircraft tracking, chat, weather text messages (METAR, TAF, etc.), and aeronautical information (NOTAMs) in a standalone application. In the framework of the HAIC project, many improvements were made in order to fulfill requirements of the onboard and ground science teams for the field campaign. The aim of this paper is to present the main improvements of the system that were implemented for the Darwin field campaign. New features of the system are related to the hardware component, the communication protocol, weather and tracking display, geomarkers on the map, and image processing and compression before onboard transfer.
2015-06-15
Journal Article
2015-01-2154
Franck Hervy, Severine Maguis, François Virion, Biagio Esposito, Hugo Pervier
Abstract The A06 test facility designed for combustor testing in altitude has been modified to be converted in an icing facility for probe testing. The objective was to be able to simulate ice crystals conditions at high altitude, high Mach number and low temperature. This facility has been upgraded in several steps extending the median size of the ice crystals produced and the ice water content range. The aero-thermal and icing capabilities have been assessed during commissioning tests. Finally, in order to prepare the calibration of the facility, some measurement techniques for cloud characterization have been selected or developed, especially for cloud uniformity measurement.
2015-06-15
Journal Article
2015-01-2155
Tadas P. Bartkus, Peter Struk, Jen-Ching Tsao
Abstract This paper describes a numerical model that simulates the thermal interaction between ice particles, water droplets, and the flowing air applicable during icing wind tunnel tests where there is significant phase-change of the cloud. It has been previously observed that test conditions, most notably temperature and humidity, change when the icing cloud is activated. It is hypothesized that the ice particles and water droplets thermally interact with the flowing air causing the air temperature and humidity to change by the time it reaches the test section. Unlike previous models where the air and particles are uncoupled, this model attempts to explain the observed changes in test conditions by coupling the conservation of mass and energy equations. The model is compared to measurements taken during wind tunnel tests simulating ice-crystal and mixed-phase icing that relate to ice accretions within turbofan engines.
2015-06-15
Technical Paper
2015-01-2144
James MacLeod, Michael Clarke, Doug Marsh
The Global Aerospace Centre for Icing and Environmental Research Inc. (GLACIER) facility is located in Thompson, Manitoba, Canada. This facility provides icing certification tests for large gas turbine engines, as well as performance, endurance and other gas turbine engine qualification testing. This globally unique outdoor engine test and certification facility was officially opened back in 2010. The prime purpose of this facility is for icing certification of aero gas turbines. As a generic engine test facility, it includes the infrastructure and test systems necessary for the installation of both current and future gas turbine engines. The GLACIER facility completed its commissioning in the winter of 2010/2011, and has now experienced five years of full icing seasons. Rolls-Royce and Pratt and Whitney have both successfully performed certification and engineering icing testing with 5 engines completing their icing certification.
2015-06-15
Technical Paper
2015-01-2142
Colin Hatch, Roger Gent, Richard Moser
Abstract Low power ice protection systems are an important research area that is highlighted in the EU Clean Sky programme. In this paper an icing wind tunnel test of a full-scale wing incorporating both an electro-thermal and a hybrid electro-thermal electro-mechanical system is described. A description of a software tool to analyse both systems as full 3D models is also given. Preliminary comparisons of test data and prediction are shown both for the electro-thermal system and the hybrid system. Initial comparisons show a reasonable correlation in the main with recommendations for a structure tear-down to identify exact internal transducer locations. Recommendations are also made with regard to undertaking tests to determine a more consistent set of mechanical failure properties of ice. Future work in the development of the tool is also discussed.
2015-06-15
Technical Paper
2015-01-2143
Christian Mendig
Abstract In the project SuLaDI (Supercooled Large Droplet Icing) research about the icing of aerofoils through large and super cooled droplets is done at the Institute of Composite Structures and Adaptive Systems (German Aerospace Center-DLR) and at the Institute of Adaptronics and Function Integration (Technische Universität Braunschweig). In the framework of the project an icing wind tunnel was built. It consists of a cooling chamber and a wind tunnel of the Eiffel-type therein. The icing of model takes place in the test section of the wind tunnel at temperatures below 0 °C. Between the flow straightener and the contraction section a spray system is built in, which sprays water droplets into the wind tunnel. The droplets are accelerated by the airstream and supercool on their way to the model. When hitting the model they freeze on it to rime ice, clear ice or mixed ice. At the model research about a structure integrated ice detection is done.
2015-06-15
Journal Article
2015-01-2156
Michael Oliver
Abstract The National Aeronautics and Space Administration (NASA) conducted a full scale ice crystal icing turbofan engine test using an obsolete Allied Signal ALF502-R5 engine in the Propulsion Systems Laboratory (PSL) at NASA Glenn Research Center. The test article used was the exact engine that experienced a loss of power event after the ingestion of ice crystals while operating at high altitude during a 1997 Honeywell flight test campaign investigating the turbofan engine ice crystal icing phenomena. The test plan included test points conducted at the known flight test campaign field event pressure altitude and at various pressure altitudes ranging from low to high throughout the engine operating envelope. The test article experienced a loss of power event at each of the altitudes tested.
2015-06-15
Technical Paper
2015-01-2247
Masao Nagamatsu
Abstract The sound localization methods are used for detection of noise source locations of prototypes of mechanical products including automobile engines. There are several types of sound localization methods. In middle frequency around 1kHz, which is most sensitive frequency for human auditory, these sound localization methods have enough resolution in their reconstructed images, and they are effective to localize the sound sources. For high frequency sound localization, the holographic type methods take long time in its measurement. To overcome this problem, I have developed a converted method of Nearfield Acoustic Holography (NAH) method, which is one of conventional holographic sound localization method. However, in low frequency, all holographic localization methods do not have enough resolution in reconstructed images. I am now developing new sound localization method, Double Nearfield Acoustic Holography (DNAH) method.
2015-06-15
Technical Paper
2015-01-2246
Kurt Veggeberg, Mike Denton
Abstract This is an overview of the development of a portable, real-time acoustic beamformer based on FPGA (Field Programmable Gate Arrays) and digital microphones for noise source identification. Microphone arrays can be a useful tool in identifying noise sources and give designers an image of noise distribution. The beamforming algorithm is a classic and efficient algorithm for signal processing of microphone arrays and is the core of many microphone array systems. High-speed real-time beamforming has not been implemented much in a portable instrument because it requires large computational resources. Utilizing a beamforming algorithm running on a Field Programmable Gate Array (FPGA), this camera is able to detect and locate both stationary and moving noise sources. A high-resolution optical camera located in the middle of the device records images at a rate of 25 frames per second.
2015-06-15
Journal Article
2015-01-2284
Chris Hocking, Simon Antonov, Arsham Shahlari
Abstract The higher cylinder peak pressure and pressure rise rate of modern diesel and gasoline fueled engines tend to increase combustion noise while customers demand lower noise. The multiple degrees of freedom in engine control and calibration mean there is more scope to influence combustion noise but this must first be measured before it can be balanced with other attributes. An efficient means to realize this is to calculate combustion noise from the in-cylinder pressure measurements that are routinely acquired as part of the engine development process. This publication reviews the techniques required to ensure accurate and precise combustion noise measurements. First, the dynamic range must be maximized by using an analogue to digital converter with sufficient number of bits and selecting an appropriate range in the test equipment.
2015-06-15
Technical Paper
2015-01-2292
Xiaorui Lu, Junda Ma
Abstract Over recent years, NVH refinement of engine is becoming increasingly important in buying decision and can significantly give competitive edge to the vehicle in market place. This paper deals with the development phase of a prototype engine in which a specific testing activity was carried out to improve the overall NVH behavior of the powertrain. In order to explain the optimization process in detail, a case study was described in this paper. First, NVH targets of the engine were set via benchmark tests on existing competitive products. Then series of baseline tests, such as 1M sound pressure level test and noise source identification, were performed on the engine. Test results indicated that an obvious breathing vibration mode exist near the intake manifold, which radiates high level noise. In order to achieve the NVH targets, a correlation validation was performed to find out the main reason that caused the vibration of intake manifold.
2015-06-15
Technical Paper
2015-01-2299
Dhanesh Purekar
Abstract NVH development of light duty diesel engines require significant collaboration with the OEM as compared to medium duty and heavy duty diesel engines. Typically, competitive benchmark studies and customer expectations define the NVH targets at the vehicle level and are subsequently cascaded down to the powertrain level. For engine manufacturing companies like Cummins Inc., it is imperative to work closely with OEM to deliver on the NVH expectations. In certain situations, engine level NVH targets needs to be demonstrated in the OEM or 3rd party acoustic test facility for customer satisfaction or commercial purposes. Engine noise tests across different noise test facilities may introduce some variation due to differences in the acoustic test facilities, test hardware, instrumentation differences, etc. In addition, the engine itself is a major source of variation.
2015-06-15
Journal Article
2015-01-2281
Shrirang Deshpande, Randall Allemang
Abstract Spectral maps and order tracks are tools which are susceptible to improper sensor location on rotating machinery and to measurement noise. On a complex/large rotating system, the major behavior in a particular direction cannot be observed by using standard digital signal processing averaging techniques on different sensor outputs. Also, measurement noise cannot be reduced by applying averaging - due to the slew rate of the system. A newly developed technique tested on experimental data, is presented which uses singular value decomposition (SVD) as its basis to improve the observability of rotating systems. By using data acquired from multiple accelerometers on a machine, singular values - obtained from a SVD of the cross-power matrix at each 2-D point in the frequency-RPM domain - can be plotted in a color-map format similar to a RPM spectral map.
2015-06-15
Technical Paper
2015-01-2278
Rohit Ravindran, Debajit Das, Keval Kamani, P Sivaraman, Gyan Arora
Abstract Torsional vibration is a characteristic phenomenon of automotive powertrains. It can have an adverse impact on powertrain related noise as well as the durability of transmission and drivetrain components. Hence minimizing torsional vibration levels associated with powertrains has become important. In this context, accurate measurement and representation of angular acceleration is of paramount importance. A methodology was developed for in-house vehicle level torsional vibration measurement, analysis and representation of results. The evaluation of torsional vibration has two major aspects. First, the acquisition of raw rotational data and secondly, the processing of acquired data to arrive at usable information from which inferences and interpretations can be made about the behavior of the rotating element. This paper describes the development process followed for establishing a torsional vibration evaluation methodology.
2015-06-15
Journal Article
2015-01-2189
Michael Krak, Jason Dreyer, Rajendra Singh
Abstract Many powertrain structural sub-systems are often tested under steady state conditions on a dynamometer or in a full vehicle. This process (while necessary) is costly and time intensive, especially when evaluating the effect of component properties on transient phenomena, such as driveline clunk. This paper proposes a laboratory experiment that provides the following: 1) a bench experiment that demonstrates transient behavior of a non-linear clutch damper under non-rotating conditions, 2) a process to efficiently evaluate multiple non-linear clutch dampers, and 3) generates benchmark time domain data for validation of non-linear driveline simulation codes. The design of this experiment is based on a previous experimental work on clunk. A commercially available non-linear clutch damper is selected and the experiment is sized accordingly.
2015-06-15
Journal Article
2015-01-2285
Arne Nykänen, David Lennström, Roger Johnsson
Abstract Subjects who are well aware of what to judge commonly yield more consistent results in laboratory listening tests. This awareness may be raised by explicit instructions and training. However, too explicit instructions or use of only trained subjects may direct experiment results in an undesired way. An alternative is to give fairly open instructions to untrained subjects, but give the subjects a chance to get familiar with the product and context by, for example, riding a representative car under representative driving conditions before entering the laboratory. In this study, sound quality assessments of interior sounds of cars made by two groups were compared. In one group subjects were exposed to the same driving conditions that were later assessed in a laboratory listening test by taking them on a ride in one of the cars to be assessed, just before entering the laboratory. In the other group subjects made the laboratory assessments without prior car riding.
2015-06-15
Journal Article
2015-01-2328
Barbara Neuhierl, Sivapalan Senthooran, Reinier Toppinga, Anke Jäger, Maarten Brink, Timo Lemke, Philippe Moron, Raghu Mutnuri
Abstract The object of the validation study presented in this paper is a generic vehicle, the so-called SAE body, developed by a consortium of German car manufacturers (Audi, Daimler, Porsche, Volkswagen). Many experiments have been performed by the abovementioned consortium on this object in the past to investigate its behavior when exposed to fluid flow. Some of these experiments were used to validate the simulation results discussed in the present paper. It is demonstrated that the simulation of the exterior flow is able to represent the transient hydrodynamic structures and at the same time both the generation of the acoustic sources and the propagation of the acoustic waves. Performing wave number filtering allows to identify the acoustic phenomena and separate them from the hydrodynamic effects. In a next step, the noise transferred to the interior of the cabin through the glass panel was calculated, using a Statistical Energy Analysis approach.
2015-06-12
Article
Small, electrically driven propellers spaced along wing leading-edges could benefit both small and medium-size aircraft
2015-06-12
WIP Standard
AIR6511
This document shall provide the fundamental safety considerations in pursuing the design of a 48/60 VDC aircraft electrical system. This departure from the current standard of 28 VDC will provide the benefits of reducing the operational weight and fuel consumption of the aircraft by increasing the DC system voltage level.
2015-06-12
Standard
AIR6282
This standard provides a cross reference detailing current test methods used in the qualification processes of fiber optic connectors, termini and cables for aerospace, telecommunications and naval applications. The cross-reference allows the end user to select the test methods most suitable for qualifying a component, or to identify alternative test methods where a specific test is not defined in a referenced document. The standard also provides information on what area each type of referenced document has been developed for.
2015-06-12
Standard
J294_201506
This SAE Recommended Practice establishes a method of testing the structural integrity of the brake system of all new trucks, buses, and combination vehicles designed for roadway use and falling in the following classifications: a. Trucks and Bus— Over 4500 kg (10 000 lb) GVWR b. Combination of vehicle—Towing vehicle over 4500 kg 10 000 lb) GVWR The test consists of two parts: a Structural EnduranceTest followed by a Structural Ultimate Strength Test.
2015-06-12
Standard
AS9014A
These requirements are applicable to IAQG sector schemes when making use of ABs, CRBs and their auditors, for the assessment and certification/registration of supplier quality systems in accordance with the requirements of this document. The quality management system standard used by the CRB shall be 9100/9110/9120, as appropriate to the supplier's activities. It shall be applied to the supplier's complete Quality System that covers aerospace products. Sectors may use these requirements for other standards. IAQG members have committed to recognize the equivalence of certification/registration of a suppliers quality management system to either of the AS, EN or JISQ/SJAC standards. This AS provides the approval process for Auditor Authentication Bodies (AAB), training course providers, trainers and auditors who meet the requirements of AIR5493 and outlines the America's sector specific process to implement AS9104. This document is created to be in conformance with AS9104.
2015-06-10
WIP 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.
2015-06-10
WIP Standard
AS1284B
The test procedure and related limit value are intended to apply to fixed and mobile ground pressure fuel dispensing sytems and to aerial refueling tankers.
2015-06-09
Article
New surface scanning technology is being utilized by rFpro to produce digital road models with unprecedented accuracy and speed to help make autonomous driving safer.
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