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2015-06-15
Technical Paper
2015-01-2140
Emiliano Iuliano
The presence of ice crystals in deep convective clouds has become a major threat for aviation safety. As recently highlighted, once inside the engine core, ice crystals encounter a high temperature environment, so that they can either melt by convection with the warm environment or melt upon impact onto hot static components of the low-pressure components. As a consequence, a liquid film may form which, in turn, is able to capture further ice crystals by sticking mechanism. This scenario results in a significant decrease of the local surface temperature and, hence, promotes the accretion of ice. Therefore, it is clear that icing simulation capabilities have to be updated in order to be able to predict such phenomena. The paper proposes an extension of CIRA icing tools to deal with ice crystals along with supercooled water droplets.
2015-06-15
Technical Paper
2015-01-2134
Tom Currie, Dan Fuleki
There is significant recent evidence that ice crystals ingested by a jet engine at high altitude can partially melt and then accrete within the forward stages of the compressor, potentially producing a loss of performance, rollback, combustor flameout, compressor damage, etc. Several studies of this ice crystal icing (ICI) phenomenon have been conducted in the past 5 years using the RATFac (Research Altitude Test Facility) altitude chamber at the National Research Council of Canada (NRCC), which includes an icing wind tunnel capable at operating at Mach numbers (M), total pressures (po) and temperatures (To) pertinent to ICI. Humidity can also be controlled and ice particles are generated with a grinder. The ice particles are entrained in a jet of sub-freezing air blowing into the tunnel inlet. Warm air from the altitude cell also enters the tunnel, where it mixes with the cold ice-laden jet, increasing the wet-bulb temperature (Twb) and inducing particle melting.
2015-06-15
Technical Paper
2015-01-2107
Tom Currie, Dan Fuleki, Craig Davison
There is significant recent evidence that ice crystals ingested by a jet engine at high altitude can partially melt and then accrete within the forward stages of the compressor, potentially producing a loss of performance, rollback, combustor flameout, compressor damage, etc. Several studies of this ice crystal icing (ICI) phenomenon have been conducted in the past 5 years using the RATFac (Research Altitude Test Facility) altitude chamber at the National Research Council of Canada (NRCC), which includes an icing wind tunnel capable at operating at Mach numbers (M), total pressures (po) and temperatures (To) pertinent to ICI. Humidity can also be controlled and ice particles are generated with a grinder. The ice particles are entrained in a jet of sub-freezing air blowing into the tunnel inlet. Warm air from the altitude cell also enters the tunnel, where it mixes with the cold ice-laden jet, increasing the wet-bulb temperature (Twb) and inducing particle melting.
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
2015-01-2113
Ismail Gultepe, Michael Pavolonis, Binbin Zhou, Randolph Ware, Robert Rabin, William Burrows, Jason Milbrandt, Louis Garand
In this study, fog and drizzle observations collected during fog remote sensing and modeling (FRAM) and satellite applications for arctic weather and SAR operations (SAAWSO) projects at cold temperatures are analyzed to better understand icing conditions. These data are used to identify icing conditions for de-icing operations, improve ground-based in-situ and remote sensing observations, and develop numerical weather prediction (NWP) capability. Both projects took place during cold Canadian winter conditions at Yellowknife, Goose Bay, and St. John’s over the past four years. Observations were obtained by a Droplet Measuring Technologies Fog Measuring Device (FMD), a ground cloud imaging probe (GCIP), a Radiometrics Profiling Microwave Radiometer (PMWR), a Rosemount icing detector, Infrared Temperature (IRT), and surface meteorological and satellite sensors.
2015-06-15
Technical Paper
2015-01-2123
Eric Defer, Jean-Louis Brenguier, Jos De Laat, Julien Delanoe, Fabien Dezitter, Michael Faivre, Amanda Gounou, Alice Grandin, Anthony Guignard, Jan Fokke Meirink, Jean-Marc Moisselin, Frederic Parol, Alain Protat, Claudine Vanbauce
J.-L. Brenguier (1), J. De Laat (2), P. De Valk (2), E. Defer (3), J. Delanoë (3), F. Dezitter (4), M. Faivre (3), A. Gounou (1), A. Grandin (4), A. Guignard (3), J. F. Meirink (2), J.-M. Moisselin (1), F. Parol (3), C. Vanbauce (3) 1 - Météo-France 2 - KNMI 3 - CNRS 4 - AIRBUS The European FP7 High Altitude Ice Crystals (HAIC) project aims at characterizing specific environmental conditions in the vicinity of convective clouds that can lead to in-service events [1]. Academics and aeronautic industries are collaborating within 6 main research activities that include dedicated field campaigns, development of new in situ probes, space-based detection and monitoring, upgrade of on-board weather radars, improvement of ground test facilities, and modeling of melting and impingement processes. All activities are designed to enhance aircraft safety when flying in mixed phase and glaciated icing conditions.
2015-06-15
Technical Paper
2015-01-2083
Daniel Silva, Thais Bortholin, J Allan Lyrio, Luis Santos
An important issue regarding landing performance is the reference speed which determines the approved fields lengths in which a landing can take place. The critical scenario is the accumulation of ice during the holding phase followed by descent, approach and landing. The effect of icing in the landing configuration, with the high-lift devices deployed, is relevant and should be anticipated during the early design phases by simulation. Due to the complex behaviour of the flowfield, 3D CFD methods has been used but that leads to a high computational cost which might be too intensive for the preliminary design phases . The purpose of this paper is to describe a lower cost procedure combining CFD and Quasi-3D modified Weissinger´s Method [3] which provides an accurate assessment of these effects to 5% margin in ∆CL , confirmed by wind tunnel testing.
2015-06-15
Technical Paper
2015-01-2088
Richard E. Kreeger, Lakshmi Sankar, Robert Narducci, Robert Kunz
The formation of ice over lifting surfaces can affect aerodynamic performance. In the case of helicopters, this loss in lift and the increase in sectional drag forces will have a dramatic effect on vehicle performance. The ability to predict ice accumulation and the resulting degradation in rotor performance is essential to determine the limitations of rotorcraft in icing encounters. The consequences of underestimating performance degradation can be serious and so it is important to produce accurate predictions, particularly for severe icing conditions. The simulation of rotorcraft ice accretion is a challenging multidisciplinary problem that until recently has lagged in development over its counterparts in the fixed wing community. But now, several approaches for the robust coupling of a computational fluid dynamics code, a rotorcraft structural dynamics code and an ice accretion code have been demonstrated.
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
2015-01-2124
Amanda Gounou, Jean-Marc Moisselin, Frédéric Autones, Eric Défer, Dominique Levaillant, Sandra Turner, Michael Faivre, Jean-Louis Brenguier, Alice Grandin, Fabien Dezitter
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
2015-01-2116
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.
2015-06-15
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
2015-01-2112
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
2015-01-2147
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
2015-01-2138
E. Iuliano, E. Montreuil, E. Norde, E.T.A. Van der Weide, H.W.M. Hoeijmakers
In this study a comparison will be made between three Eulerian-based solvers that predict the ice crystal trajectories and impingement on a NACA-0012 airfoil. The codes are being developed within CIRA, ONERA and University of Twente, and are improvements to their in-house Eulerian codes called Imp2D/3D, CEDRE/Spiree and MooseMBIce, respectively. This cooperation between CIRA, ONERA and University of Twente was initiated in the framework of European funded project HAIC (High Altitude Ice Crystals), a large-scale integrated project which aims at enhancing aircraft safety when flying in mixed phase and glaciated icing conditions. The numerical codes differ by the general architecture and implementation of the cloud particle size distribution. Imp2D/3D and MooseMBIce are based on a finite volume approach for multi-block structured grid. CEDRE/Spiree also employs a finite volume approach but handles generalized unstructured grids.
2015-06-15
Technical Paper
2015-01-2122
Cameron Butler, Eric Loth
INTRODUCTION To support a collaborative research project aimed at studying icing on large-scale, swept wings, unsteady simulations were performed on test articles with and without icing in NASA Glenn’s Icing Research Tunnel (IRT). The models being tested are all swept hybrid models designed to have the same leading-edge geometry as a 65% scaled version of the Common Research Model (CRM). Three models were designed as hybrid airfoils where the leading edge geometry and flow field matched that of the CRM, but the rest of the airfoil was reduced substantially in length to accommodate the tunnel cross-section. This hybrid design allows for the largest leading-edge which avoids complex issues associated with geometric scaling in icing conditions. To investigate the effect of sweep along the wing, three different test models are investigated to represent different spanwise locations along the CRM, from inboard, mid-span and outboard.
2015-06-15
Technical Paper
2015-01-2146
Matthew Feulner, Shengfang Liao, Becky Rose, Xuejun Liu
Matt Feulner, Shengfang Liao, Becky Rose and Xuejun Liu Pratt & Whitney, United Technologies Corporation A through-flow based Monte Carlo particle trajectory simulation is used to calculate the ice crystal paths in the low pressure compressor of a high bypass ratio turbofan engine. The trajectory model includes a statistical ice particle breakup model due to impact on the engine surfaces. Stage-by-stage ice water content, particle size and particle velocity distributions are generated at multiple flight conditions and engine power conditions. The simulation results prompt the need to properly set up boundary conditions for component or cascade testing.
2015-05-20
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2015-04-14
Technical Paper
2015-01-0219
Rodrigo Felix, John Economou, Kevin Knowles
Abstract Starting January 2015 the government of the United Kingdom will allow driverless cars on public roads. From a first glance this can and should be seen as a great step towards the adoption of autonomous vehicles. Yet as any new technology driverless vehicles carry with them many new risks and disadvantages that need to be understood and protected against in order for the introduction of said systems into the market place to be a long lasting and fruitful one. The present work will look at the possible safety and security risks posed by the use of Light Detection and Ranging (LiDAR) systems on the open road, motivated by the fact that many projected autonomous vehicle concept systems rely on them for object detection and avoidance.
2015-04-14
Technical Paper
2015-01-0717
Anindya Deb, G S Venkatesh, Ashok Mache
Abstract The usage of lightweight materials such as plastics and their derivatives continues to increase in automobiles driven by the urgency for weight reduction. For structural performance, body components such as A-pillar or B-pillar trim, instrument panel, etc. have to meet various requirements including resistance to penetration and energy absorption capability under impact indentation. A range of plain and reinforced thermoplastics and thermosetting plastics has been considered in the present study in the form of plates which are subject to low velocity perforation in a drop-weight impact testing set-up with a rigid cylindrical indenter fitted to a tup. The tested plates are made of polypropylene (PP), nanoclay-reinforced PP of various percentages of nanoclay content, wood-PP composites of different volume fractions of wood fiber, a jute-polyester composite, and a hybrid jute-polyester reinforced with steel.
2015-04-14
Technical Paper
2015-01-0214
Ramya Deshpande, Krishnan Kutty, Shanmugaraj Mani
In modern cars, the Advanced Driver Assistance Systems (ADAS) is cardinal point for safety and regulation. The proposed method detects visual saliency region in a given image. Multiple ADAS systems require number of sensors and multicore processors for fast processing of data in real time, which leads to the increase in cost. In order to balance the cost and safety, the system should process only required information and ignore the rest. Human visual system perceives only important content in a scene while leaving rest of portions unprocessed. The proposed method aims to model this behavior of human visual system in computer vision/image processing applications for eliminating non salient objects from an image. A region is said to be salient, if its appearance is unique. In our method, the saliency in still images is computed by local color contrast difference between the regions in Lab space.
2015-04-14
Technical Paper
2015-01-0739
John Patalak, Thomas Gideon
Abstract Over the last decade large safety improvements have been made in crash protection for motorsports drivers. It has been well established that in side and rear impacts the driver seat provides the primary source for occupant retention and restraint. Beginning in the 2015 season, NASCAR®'s (National Association for Stock Car Auto Racing, Inc) Sprint Cup Series will require driver seats which have all seat belt restraint system anchorage locations integrated internally to the seat with a minimum of seven anchorage locations. This paper describes the development of the quasi-static test for the seat integrated seat belt restraint system portion of the NASCAR Seat Submission and Test Protocol Criteria. It reviews the methodology used to develop the testing including the developmental dynamic sled tests.
2015-04-14
Technical Paper
2015-01-0130
Julio Rodriguez, Ken Rogich, Philip Pidgeon, Kim Alexander, John R. Wagner
Abstract Driving skills and driving experience develop differently between a civilian and a military service member. Since 2000, the Department of Defense reports that two-thirds of non-related to war fatalities among active duty service members were due to transportation-related incidents. In addition, vehicle crashes are the leading non-related to war cause of both fatalities and serious injuries among active duty Marines. A pilot safe driving program for Marines was jointly developed by the Richard Petty Driving Experience and Clemson University Automotive Safety Research Institute. The pilot program includes four modules based on leading causes of vehicle crashes, and uses classroom and behind the wheel components to improve and reinforce safe driving skills and knowledge. The assessment results of this pilot program conducted with 192 Marines in September 2011 at Camp LeJeune, NC are presented and discussed.
2015-04-14
Technical Paper
2015-01-1415
Yasuhiro Matsui, Shoko Oikawa
Abstract Fatal injuries suffered by cyclists in vehicle-versus-cyclist accidents are investigated to provide information for the introduction of safety countermeasures. We analyzed characteristics of cyclist injuries in real fatal accidents and compared them with severity levels of head injury in impact tests against a road surface. In the accident analyses, we investigated the main body regions whose injuries led to fatalities using a macro vehicle-cyclist accident database of the Institute for Traffic Accident Research and Data Analysis of Japan. Using data from 2009 to 2013, we investigated the frequency of cyclist fatalities by gender, age group, vehicle speed, and the source of fatal head injury (impact with the vehicle or road surface). Results indicated that head injuries are the most common cause of cyclist fatalities in car-cyclist accidents.
2015-04-14
Technical Paper
2015-01-1419
Raymond M. Brach
Abstract Numerous algebraic formulas and mathematical models exist for the reconstruction of vehicle speed of a vehicle-pedestrian collision using pedestrian throw distance. Unfortunately a common occurrence is that the throw distance is not known because no evidence exists to locate the point of impact. When this is the case almost all formulas and models lose their utility. The model developed by Han and Brach published by SAE in 2001 is an exception because it can reconstruct vehicle speed based on the distance between the rest positions of the vehicle and pedestrian. The Han-Brach model is comprehensive and contains crash parameters such as pedestrian launch angle, height of the center of gravity of the pedestrian at launch, pedestrian-road surface friction, vehicle-road surface friction, road grade angle, etc. Such an approach provides versatility and allows variations of these variables to be taken into account for investigation of uncertainty.
2015-04-14
Technical Paper
2015-01-0493
Ying Wang, Ye Wang, You Qu, Sumin Zhang, Weiwen Deng
Abstract Vision-based Advanced Driver Assistance Systems has achieved rapid growth in recent years. Since vehicle field testing under various driving scenarios can be costly, tedious, unrepeatable, and often dangerous, simulation has thus become an effective means that reduces or partially replaces the conventional field testing in the early development stage. However, most of the commercial tools are lack of elaborate lens/sensor models for the vehicle mounted cameras. This paper presents the system-based camera modeling method integrated virtual environment for vision-based ADAS design, development and testing. We present how to simulate two types of cameras with virtual 3D models and graphic render: Pinhole camera and Fisheye camera. We also give out an application named Envelope based on pinhole camera model which refers to the coverage of Field-of-Views (FOVs) of one or more cameras projected to a specific plane.
2015-04-14
Technical Paper
2015-01-0215
Reena Kumari Behera, Smita Nair, Vinay Vaidya
Abstract This paper presents a simple yet novel approach to remove redundant data from outdoor scenes, thus finding significant application in Advanced Driver Assistance Systems (ADAS). A captured outdoor scene has two main parts, the ground region consisting of the road area along with other lane markings and the background region consisting of various structures, trees, sky etc. To extract the ground region, first the yellow and white road markings are segmented based on the HSI (Hue Saturation Intensity) color model and these regions are filled with the surrounding road color. Further the background region is segmented based on the Lab (Color-opponent) color model, which shows significant improvement as compared to other color spaces. To extract the background region such as the sky or ground region, it is assumed that the top and bottom most portions of the image does not consist of useful information.
2015-04-14
Technical Paper
2015-01-0213
Vinuchackravarthy Senthamilarasu, Anusha Baskaran, Krishnan Kutty
Abstract In the research field of automotive systems, Advanced Driver Assistance Systems (ADAS) are gaining paramount importance. As the significance for such systems increase, the challenges associated with it also increases. These challenges can arise due to technology, human factors, or due to natural elements (haze, fog, rain etc.). Among these, natural challenges, especially haze, pose a major setback for technologies depending on vision sensors. It is a known fact that the presence of haze in the atmosphere degrades the driver's visibility as well as the information available with the vision based ADAS. To ensure reliability of ADAS in different climatic conditions, it is vital to get back the information of the scene degraded by haze prior to analyzing the images. In this paper, the proposed work addresses this challenge with a novel and faster image preprocessing technique that can enhances the quality of haze affected images both in terms of visibility and visual perception.
2015-04-14
Technical Paper
2015-01-0369
Rupesh Sonu Kakade
Abstract In addition to the thermal comfort of the vehicle occupants, their safety by ensuring adequate visibility is an objective of the automotive climate control system. An integrated dew point and glass temperature sensor is widely used among several other technologies to detect risk of fog formation on the cabin side (or inner) surface of the windshield. The erroneous information from a sensor such as the measurement lag can cause imperfect visibility due to the delayed response of the climate control system. Also the high value, low cost vehicles may not have this sensor due to its high cost. A differential equation based model of the cabin air humidity is proposed to calculate in real-time specific humidity of the passenger compartment air. The specific humidity is used along with the windshield surface temperature to determine relative humidity of air and therefore, the risk of fog formation on the interior surface of a windshield.
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