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Viewing 61 to 90 of 16152
2015-06-15
Technical Paper
2015-01-2086
Matthew Grzych, Terrance Tritz, Jeanne Mason, Melissa Bravin, Anna Sharpsten
The significant problem of engine power-loss and damage associated with ice crystal icing (ICI) was discussed in Mason et al [1]. These engine events included engine surge, stall, flameout, rollback and compressor damage and were connected to the ingestion of high concentrations of ice crystals associated with deep convective clouds. Since that time, several industry and government collaborations have taken steps to address the many technological requirements identified by the Engine Harmonization Working Group (EHWG) in 2007 [2]. The EHWG identified the need for in-situ measurements of ice concentration and size distribution to aid in the development of engine test facilities and methods to simulate the environment. Researchers are also addressing a second technology requirement identified by the EHWG: fundamental studies on the physics of ice accretion in the engine. Both efforts require study environments to be similar to the ones that cause in-service engine events.
2015-06-15
Technical Paper
2015-01-2132
David L. Rigby, Joseph Veres, Colin Bidwell
Three dimensional Navier-Stokes simulations of the Honeywell ALF502 low pressure compressor using the NASA Glenn code Glenn-HT have been carried out. A total of eight operating points were investigated. These operating points are at, or near, points where engine icing has been determined to be likely. The results of this study are expected to be used immediately, and in the future, for further analysis such as predicting collection efficiency of ice particles and ice growth rates at various locations in the compressor. A mixing plane boundary condition is used between each blade row, resulting in convergence to steady state within each blade row. Results for two levels of approximation are discussed. The first set of cases were run allowing all of the solid surfaces to slip (i.e. inviscid). That is, the velocity boundary layers are not resolved. This allows for much smaller grids and shorter run times.
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
The PLANET (PLAne-NETwork) 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 and weather text messages (METAR, TAF, NOTAM, etc.) in a standalone application. In the frame of the HAIC (High Altitude Ice Crystals) project, many improvements were made in order to fulfill requirements of the on-board and ground science teams. The aim of this paper is to present the main improvements of the PLANET System that were implemented for the Darwin field campaign. The goal of the flight tests for high IWC characterization were to collect cloud data in deep convective clouds, provide 99th percentile total water content statistics and other relevant parameters of such clouds as a function of distance scale to industry and regulators.
2015-06-15
Technical Paper
2015-01-2124
Amanda Gounou, Jean-Marc Moisselin, Frédéric Autones, Dominique Levaillant, Jean-Louis Brenguier, Eric Défer, Michael Faivre, Alice Grandin, Fabien Dezitter, Sandra Turner
Icing conditions are often encountered in the vicinity of deep convective clouds. Nowcasting of these conditions would be of a great help for flight safety and air traffic management but still remains challenging. In the framework of the HAIC (High Altitude Ice Crystals) project [1], the nowcasting of icing conditions due to ice particles is investigated. A major field campaign has been carried out in Darwin, Australia, from 16th January to 7th March 2014, during the rainy season to sample meteorological conditions potentially leading to icing [2]. There were 23 research flights with on-board in-situ and remote sensing instruments measuring or estimating ice water content within oceanic mature thunderstorms which offered a great opportunity to implement, test and cross-validate nowcasting tools to detect and track cloud regions of high ice water content.
2015-06-15
Technical Paper
2015-01-2153
David Serke, Michael King, Andrew Reehorst
In early 2015, the NASA Glenn Research Center will conduct a field campaign based out of Cleveland, Ohio with 60 flight hours on the Twin Otter icing research aircraft. The purpose of the field campaign is to test several prototype algorithms meant to detect the location and severity of in-flight icing within the terminal airspace. The terminal airspace is currently defined as within 25 kilometers horizontal distance of the terminal, which in this case was Hopkins International Airport in Cleveland. Two new and improved algorithms have been developed and will be operated during the field campaign. The first is the 'NASA Icing Remote Sensing System', or NIRSS. NASA and the National Center for Atmospheric Research have developed this icing remote sensing technology which has demonstrated skill at detecting and classifying icing hazards in a vertical column above an instrumented ground station1,2.
2015-06-15
Technical Paper
2015-01-2112
Thomas Schlegl, Michael Moser, Hubert Zangl
We present a system of completely autarkic temperature and capacitive icing sensors for aircraft. The consequences of icing on aircraft are described, for example, in [1] and [2]. Flexible (i.e. bendable) sensors, which are truly wireless and do not require maintenance, are easily mounted to almost any point on the aircraft surface (e.g. wings, fuselage, rudder, elevator, etc.). The entire sensing unit has a size of less than 100 mm times 170 mm (3.397 in times 6.693 in). The overall thickness can be kept lower than 2 mm (0.079 in) at the current status of development. It comprises the sensor front-end, processing electronics, buffered solar harvesting and a low-power radio frequency transmitter. The system transmits measurement results via an RF link to a monitoring system, which comprises a receiver antenna and a receiver circuit located at a suitable position on the aircraft. The employed sensor principle was first suggested in [3].
2015-06-15
Technical Paper
2015-01-2105
Darren Glenn Jackson
Aircraft icing has been a focus of the aviation industry for many years. While regulations existed for the certification of aircraft and engine ice protection systems, no FAA or EASA regulations pertaining to certification of ice detection systems existed for much of this time. Interim policy on ice detection systems has been issued through the form of AC20-73A as well as FAA Issue Papers and EASA Certification Review Items to deal mainly with Primary Ice Detection Systems. A few years ago, the FAA released an update to FAR 25.1419 which provided the framework for the usage of ice detection systems on aircraft. As a result of the ATR-72 crash in Roselawn, Indiana due to Supercooled Large Droplets (SLD) along with the Air France Flight 447 accident and numerous engine flame-outs due to ice crystals, both the FAA and EASA have developed new regulations to address these concerns.
2015-06-15
Technical Paper
2015-01-2148
Erdem Ayan, Serkan Ozgen, Canibek Murat, Erhan Tarhan
Ice crystal ingestion to aircraft engines may cause ice to accrete on internal components, leading to flameout, mechanical damage, rollback, etc. Many incidents occur due to the engine failures especially at high altitude convective weather conditions. Thus, in the framework of HAIC FP7 European project, the physical mechanisms of ice accretion on surfaces exposed to ice-crystal and mixed-phase conditions are investigated. Within the HAIC FP7 European project, TAI will implement models related to the ice crystal accretion calculation to the existing ice accumulation prediction program for droplets, namely TAICE. Considered models include heat transfer & phase change model, drag model and impact model. Moreover, trajectory model and Extended Messinger Model require some modifications to be used for ice crystal accretion predictions.
2015-06-15
Technical Paper
2015-01-2154
Franck Hervy, Severine Maguis, François Virion, Biagio Esposito, Hugo Pervier
In 2010, DGA Aero-engine Testing decided to develop a capability to reproduce glaciated icing conditions in one of its altitude test facilities able to simulate low temperature and high altitude conditions. The facility selected for this purpose, named A06, originally developed for relight and flame out testing of combustors has been modified to integrate a small experimental test cell instead of a combustor. A specific converging nozzle has been implemented to reach Mach number up to 0.85 allowing tests in free jet configuration on small test articles like probes. In addition, for ice crystals generation, spray bars have been inserted upstream the test cell. Tests have been performed to define the operating envelope in terms of temperature, altitude, Mach number, humidity and ice water content but also where the ice crystals generation system can operate continuously.
2015-06-15
Technical Paper
2015-01-2130
Melissa Bravin, J. Walter Strapp, Jeanne Mason
In response to the occurrence of jet engine powerloss and damage events associated with deep convective clouds containing high concentrations of ice crystals, several research efforts are underway. Several flight measurement programs devoted to the collection of in-situ and remote sensing of clouds have been conducted over the past few years. The most recent in Darwin, Australia, from January-March 2014, and its follow-up planned for Cayenne, French Guiana, in May 2015, involve the use of a highly instrumented research aircraft with instrumentation specially designed to make accurate in-situ total water content (TWC) and median mass diameter (MMD) measurements of the high concentration areas of deep convection. The data will be used for atmospheric research related to understanding the microphysics of deep convection, and improving the ability to predict, detect and avoid these clouds.
2015-06-15
Technical Paper
2015-01-2163
Caio Fuzaro Rafael, Diogo Mendes Pio, Guilherme A. Lima da Silva
The present paper shows integral boundary-layer solutions and finite-volume Reynolds-Averaged Navier Stokes (RANS) Computational Fluid Dynamics (CFD) results for flow around three airfoils: NACA 8H12, MMB-V2 and NACA0012. The objective of the present paper is to verify and compare results of a proposed two-equation integral model to those of a traditional one-equation integral model used by classic 2D icing codes and previous anti-ice works. In addition, the present paper compares the results of both proposed and traditional integral codes to CFD results and, whenever possible - validate with experimental data. A numerical code that solves integral equations of boundary layer - with transition onset and length predictions as well as the intermittency evolution - is implemented based on different literature models.
2015-06-15
Technical Paper
2015-01-2144
James MacLeod, Michael Clarke, Doug Marsh
The GLACIER Icing Facility – Lessons Learnt in the first Five Years of Operation J.D. MacLeod M. Clarke National Research Council of Canada Rolls-Royce plc Gas Turbine Laboratory Civil Aerospace Ottawa, ON Derby, UK Abstract 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. The facility provides the aviation industry with the required environmental conditions (by virtue of its location), and the capability to meet the growing demands for icing certifications and other adverse cold weather conditions.
2015-06-15
Technical Paper
2015-01-2092
David M. Orchard, Catherine Clark, Myron Oleskiw
As a result of a series of international collaborative projects to measure and assess aircraft icing environments that contain Supercooled Large Droplets (SLDs), it has been demonstrated that the current icing envelopes, e.g., Code of Federal Regulations (CFR) 14 Part 25 Appendix C, do not adequately capture conditions where SLDs are present. Consequently, regulatory authorities are considering extensions to the certification requirements to include SLD environments. In order to demonstrate compliance to an updated icing certification that includes SLD conditions, airframe and aircraft component manufactures will have an increased need for access to test facilities that can simulate this environment. To address this need, a series of tests have been conducted within the NRC’s Altitude Icing Wind Tunnel (AIWT) to examine the feasibility of expanding its current capabilities to include the SLD icing envelope.
2015-06-15
Technical Paper
2015-01-2101
Hai Li, Ilia Roisman, Cameron Tropea
Airframe icing is a topic of vital importance in aviation industry because it is mainly concerned with the safe and efficient operation of aircraft under all weather conditions. Over the last 15 years the role of supercooled large droplets (SLD) in aircraft icing has received increased attention. Recent meteorological investigations on icing weather have highlighted the existence of icing cloud characteristics beyond the actual certification envelope defined by the 14 CFR Part 25 Appendix C: Atmospheric Icing Conditions for Aircraft Certification, which accounts for an icing envelope characterized by water droplet diameters up to 50 μm. The mechanisms of impact and solidification of SLD are still not completely understood. The main subject of the present study is an investigation of impact of a supercooled drop onto a superhydrophobic substrate. Drop impact, spreading and rebound are observed using a high-speed video system.
2015-06-15
Technical Paper
2015-01-2162
Krzysztof Szilder, Edward Lozowski
Atmospheric icing resulting from freezing rain, freezing drizzle and freezing cloud droplets occurs when airborne supercooled water drops freeze on objects they encounter. This process is especially hazardous to aircraft, when the build-up of ice changes the stability and control characteristics of the aerodynamic surfaces. Ice can also be shed with disastrous consequences, if it is ingested into engines, strikes the aircraft or leads to unbalanced aerodynamics forces. Ice accretion is a complex phenomenon involving 3-D multi-phase flow, heat transfer, and gravitational, viscous, surface tension and shear forces. An ability to predict how ice accretes on engineering structures is essential to the prediction of its associated aerodynamic penalties. We have developed an original icing modelling capability, called the “morphogenetic” approach, based on a discrete formulation and emulation of ice formation physics.
2015-06-15
Technical Paper
2015-01-2116
Peter Struk, Tadas Bartkus, Jen-Ching Tsao, Tom Currie, Dan Fuleki
This paper describes ice accretion measurements from experiments conducted at the National Research Council (NRC) of Canada’s Research Altitude Test Facility during 2012. Due to numerous engine power-loss events associated with high-altitude convective weather, potential ice accretion within an engine due to ice-crystal ingestion is being investigated collaboratively by NASA and NRC. These investigations examine the physical mechanisms of ice accretion on surfaces exposed to ice-crystal and mixed-phase conditions, similar to those believed to exist in core compressor regions of jet engines. A further objective of these tests is to examine scaling effects since altitude appears to play a key role in this icing process. While the 2012 experiments had multiple objectives such as cloud characterization and the evaluation of imaging techniques, several tests were dedicated to observe ice accretions using both a NACA 0012 and a wedge-shaped airfoil.
2015-05-20
Book
This is the electronic format of the Journal.
2015-04-16
Book
Robert J. Flemming
The effects of inflight atmospheric icing can be devastating to aircraft. Universities and industry have been hard at work to respond to the challenge of maintaining flight safety in all weather conditions. Proposed changes in the regulations for operation in icing conditions are sure to keep this type of research and development at its highest level. This is especially true for the effects of ice crystals in the atmosphere, and for the threat associated with supercooled large drop (SLD) icing. This collection of ten SAE International technical papers brings together vital contributions to the subject. Icing on aircraft surfaces would not be a problem if a material were discovered that prevented the freezing and accretion of supercooled drops. Many options that appeared to have promising icephobic properties have had serious shortfalls in durability.
2015-04-15
Book
“Spotlight on Design” features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing costs, improving quality, safety or environmental impact, and achieving regulatory compliance. Sensors are essential to the safety, efficiency, and dependability of modern vehicles. Crash sensors can anticipate a collision faster than humans would, and tire pressure sensors can alert the driver or pilot in case action is needed. In the episode “Sensors: Advanced Safety” (20:36) Continental engineers look at the evolution of passive safety systems, discuss the changes in sensors over the last ten years and what is coming next. Engineers at Meggitt demonstrate how tire pressure monitoring system sensors for aerospace are built and tested.
2015-04-15
Book
“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Extreme environment sensors require extreme environment cables that can reliably perform in temperatures up to 2300° F, withstand intense vibration, and have extraordinary strength.
2015-04-15
Book
“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Automated driving is made possible through the data acquisition and processing of many different kinds of sensors working in unison. Sensors, cameras, radar, and lidar must work cohesively together to safely provide automated features. In the episode “Automated Vehicles: Converging Sensor Data” (8:01), engineers from IAV Automotive Engineering discuss the challenges associated with the sensor data fusion, and one of Continental North America’s technical teams demonstrate how sensors, radars, and safety systems converge to enable higher levels of automated driving.
2015-04-15
Book
“Spotlight on Design” features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. In the episode “Automated Vehicles: Sensors and Future Technologies” (24:31), highly automated driving is looked at in detail as the culmination of years of research in automotive technology, sensors, infrastructure, software, and systems integration. Real-life case studies show how organizations are actually developing solutions to the challenge of making cars safer with less driver intervention. IAV Automotive Engineering demonstrates how a highly automated vehicle capable of lane changing was created.
2015-04-14
Collection
This technical paper collectopm places an emphasis on, but not limited to, innovative ideas to enhance automotive safety with improved material constitutive modeling, analysis method developments, simulation and pre/post processing tools, optimization techniques, crash code developments, finite element model updating, model validation and verification techniques, dummies and occupants, restraint systems, passive safety as well as lightweight material applications and designs.
2015-04-14
Collection
Active Safety and Driver assistance systems are gaining importance as many passive safety systems have already been found to have yielded significant safety benefits that are possible from the deployment of those systems in the fleet. Similar success will much depend upon how fast these systems proliferate the entire passenger vehicle fleet. It will also depend on the deployment strategies used by the industry and the government as well as consumer acceptance and market demand for these systems. Additionally, opportunities exist to use the information gained from the various onboard sensors and vision systems in active safety systems for improving the effectiveness of today’s passive safety systems such as seat belts, airbags, and post-crash safety systems even further by the integration of active and passive safety systems.
2015-04-14
Collection
The pedestrian and cyclist safety session focuses on research and development efforts aimed at protecting pedestrians and cyclists in the event of vehicle impact. Papers covern injury biomechanics, vehicle design, dummy and impactor development, computational modeling, regulations and consumer assessment testing, active safety and collision avoidance.
2015-04-14
Collection
The Occupant Restraints technical paper collection highlights papers that document new research on the restraint topics of airbags, seat belts, inflatable bolsters/seat belts, knee bolsters, Child Restraint Systems (CRS) and other related areas. These papers could include several of the following: technology description, occupant performance considerations, field data studies, development/validation methodology / results, CAE/Finite Element methods/results, packaging, and implementation / performance challenges.
2015-04-14
WIP Standard
J2944
This Recommended Practice, Operational Definitions of Driving Performance Measures and Statistics, provides functional definitions of and guidance for performance measures and statistics concerned with driving on roadways. As a consequence, measurements and statistics will be calculated and reported in a consistent manner in SAE and ISO standards, journal articles proceedings papers, technical reports, and presentations so that the procedures and results can be more readily compared. Only measures and statistics pertaining to driver/vehicle responses that affect the lateral and longitudinal positioning of a road vehicle are currently provided in this document. Measures and statistics covering other aspects of driving performance may be included in future editions. For eye glance-related measures and statistics, see SAE J2396 (Society of Automotive Engineers, 2007) and ISO 15007-1 (International Standards Organization, 2002).
2015-04-14
WIP Standard
J2938
This SAE Recommended Practice provides test procedures, requirements, and guidelines for the methods of the measurement of lumen maintenance of LED devices (packages, arrays and modules). This document does not provide guidance or make any recommendation regarding predictive estimations or extrapolation for lumen maintenance beyond the limits of the lumen maintenance determined from actual measurements.
2015-04-14
Technical Paper
2015-01-1217
Changhong Liu, Lin Liu
Abstract Many problems are associated with the large battery operation current, such as battery overheating, lithium plating, and mechanical structural instability of battery materials. All these problems may cause battery safety issues in fuel cell hybrid vehicles (FCHVs), e.g., battery explosions and thermal runaway have been reported and may cause public anxiety about FCHVs. Previous researches on FCHV power management strategy have focused on minimizing fuel consumption. But more attention needs to put on the battery current constraint for analysis of battery state of charge (SOC) and battery state of health (SOH). This research targets optimizing the FCHV battery pack operation within a safe current range through power management strategy to increase the safety of the battery pack while improving battery usage via SOC control. Battery SOH is also evaluated in the study.
2015-04-14
Technical Paper
2015-01-1369
Kai Liu, Andres Tovar, Emily Nutwell, Duane Detwiler
Abstract This work introduces a new design algorithm to optimize progressively folding thin-walled structures and in order to improve automotive crashworthiness. The proposed design algorithm is composed of three stages: conceptual thickness distribution, design parameterization, and multi-objective design optimization. The conceptual thickness distribution stage generates an innovative design using a novel one-iteration compliant mechanism approach that triggers progressive folding even on irregular structures under oblique impact. The design parameterization stage optimally segments the conceptual design into a reduced number of clusters using a machine learning K-means algorithm. Finally, the multi-objective design optimization stage finds non-dominated designs of maximum specific energy absorption and minimum peak crushing force.
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