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Viewing 1 to 30 of 104148
2015-06-15
Technical Paper
2015-01-2082
Andreas Tramposch, Wolfgang Hassler, Reinhard F.A. Puffing
Certain operating modes of the Environmental Control System (ECS) of passenger aircraft are accompanied with significant frost formation in a number of pivotal parts of the system. These icing phenomena mostly occur during ground operation in hot regions with high humidity and are caused by the presence of remnant water in the preconditioned airstream. This water may appear – depending on the operating conditions – in the form of liquid water droplets, frozen particles and also water vapor. Icing conditions particularly prevail downstream of the AC packs and, as a consequence, ice formation takes place in the Pack Discharge Duct (PDD) and the mixing manifold. The ice thereby accumulates at the walls of the PDD and the mixing manifold and leads to a change of the flow geometry, which particularly increases the pressure drop in the system. This reduces the efficiency of the AC system and may even lead to a shutdown (of parts) of the system.
2015-06-15
Technical Paper
2015-01-2087
Delphine Leroy, Emmanuel Fontaine, Alfons Schwarzenboeck, J. Walter Strapp, Lyle Lilie, Julien Delanoe, Alain Protat, Fabien Dezitter, Alice Grandin
Title: HAIC/HIWC field campaign - specific findings on PSD microphysics in high IWC regions from in situ measurements: crystal size distribution characteristics, ice density, and median mass diameters Authors: Delphine Leroy (CNRS-LaMP), Emmanuel Fontaine (CNRS-LaMP), Alfons Schwarzenboeck (CNRS-LaMP), J.
2015-06-15
Technical Paper
2015-01-2090
Serkan Ozgen, Volkan Tatar, Nermin Ugur, Ilhan Gorgulu
This study aims to assess the effects of icing conditions on benchmark and real engine nacelle geometries. The calculations are done in both liquid and glaciated phase clouds. The computational tool used for prediction consists of four main modules; flow field solution, trajectory calculations, thermodynamic model and ice growth calculation. The flow solver in the current computational tool is a panel solver where the strengths of the singularity elements are varied in order to meet the required mass flow rate through the nacelle/engine. A RANS solver is in the process of being integrated into the current solver. The trajectory calculations are done both for liquid phase clouds including SLD effects like breakup and splash, and for solid/mixed phase clouds. The latter will take ice crystal drag coefficient, phase change, non-uniform flow field temperature, impact phenomena like erosion, bounce, etc. into account. The ice growth model is the Extended Messinger Model.
2015-06-15
Technical Paper
2015-01-2096
The correct prediction of ice accretion on aircraft surfaces by simulation necessitates a good prediction of friction coefficient and heat transfer coefficient. After icing process, surface roughness induces high increase of friction and heat transfer, but simple Reynolds analogy is no longer valid. An experimental campaign is conducted in order to provide a database for numerical model development in the simple configuration of a flat plate under turbulent airflow conditions. The flat plate model is placed in the centre of the test section of a windtunnel with an improved temperature regulation. The test model is designed according to constraints for the identification of friction and heat transfer coefficients. It includes three identical resin plates which are moulded to obtain a specified roughness on the upper surface exposed to the flow. The latest resin plate is heated on its lower face by an electrical heater connected to a temperature regulator.
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
2015-01-2154
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
2015-01-2161
Kazem Hasanzadeh, Dorian Pena, Yannick Hoarau, Eric Laurendeau
The paper will present the framework of fully automated two/three dimensional ice accretion simulation package NSMB3D-ICE, with emphasis on the remeshing step. The NSMB3D-ICE Navier-Stokes code, coupled to an Eulerian droplet module and iterative Messinger thermodynamic model, can perform multi time-steps ice accretion simulations via an automated multi-block elliptic/parabolic grid generation code (NSGRID3D). Attention is paid to the efficiency and robustness of the numerical procedure especially for complex 3D glaze ice simulation. The new automated multi time-step icing code NSMB3D-ICE/NSGRID3D is validated and verified using several icing case studies such as the GLC305-3D rime and glaze ice cases. The Navier-Stokes flow solver NSMB3D is a finite volume three-dimensional multi-block Euler/Navier-Stokes flow solver developed by J. Vos et al. [1-3].
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, 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
2015-01-2112
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
2015-01-2150
Katsuaki Morita, Hirotaka Sakaue, Taro Tanaka, Takeshi Yoshida, Nadine Rehfeld, Andreas Brinkmann, Katrin Lummer, Gerhard Pauly
Anti-icing or deicing of an aircraft is necessary for a safe flight operation. We have started the JEDI-ACE project (Japan-European De-Icing Aircraft Collaborative Exploration) as collaboration between EU nations and Japan since November 2012. This project aims to provide an innovative concept of an integrated ice protection system. An overview of this project will be presented in a separate paper by JEDI-ACE team. In this project, Japan Aerospace Exploration Agency (JAXA) develops icephobic coatings as an anti-icing purpose. Coating developments by Fuji Heavy Industries Ltd and Fraunhofer IFAM will be presented in separate papers by those institutions. In this paper, we will include our progress summary of the coating development and evaluation by JAXA. We will include our chemical components of the developed coatings as well as the evaluation of those coating. The developed coating is based on poly-tetra fluoroethylene (PTFE) particle bonded by a polymer.
2015-06-15
Technical Paper
2015-01-2093
Maxime Henno
A numerical tool has been developed for predicting the unsteady behavior of the thermal wing ice protection systems (WIPS). The code was developed to account for a multi-layer composite structure. The performance predictions of a WIPS integrated into a metallic or into a composite structure can thus be achieved. The tool enables the simulation of unsteady anti-icing operations, for example, the WIPS may be activated with delay after entering into the icing conditions. In this case, ice starts to accrete on the leading edge before the WIPS heats up the skin. Another example is the ground activation of the WIPS for several seconds to check its functionality: low external cooling may cause high thermal constraints that must be estimated with accuracy to avoid adverse effects on the structure. The simulations give further opportunities compared to the current practice.
2015-06-15
Technical Paper
2015-01-2145
Sara Gonzalez Ruiz, Gertjan Glabeke, Jeroen Vanbeeck
The high number of incidents reported in the last decades from aircrafts flying through convective clouds has raised awareness of the impact that ice crystals have on the safety of airplanes. The mass of ice crystals contained in the flow, and the size of these particles, are important parameters that must be taken into account when dealing with these types of clouds. The icing wind tunnels allow to simulate the atmospheric flight conditions for ground testing, which simplifies the study of the effects that the ice crystals have on different parts of the aircrafts, while it also allows to test different techniques for clouds characterization. They can operate at both glaciated conditions, where the flow is composed only of ice crystals, and mixed phase conditions, where also supercooled liquid water droplets are present in the flow. Nowadays, one of the main issues for wind tunnel testing is the calibration of the wind tunnel itself.
2015-06-15
Technical Paper
2015-01-2097
Timothy A. Shannon, Stephen T. McClain
As ice begins to accrete on an aircraft in flight, the stochastic nature of the droplet impingement process dictates that the accreted ice is uneven along the surface resulting in roughness. Because of the varying convection along the surface and local shear rates along the surface, the resulting roughness statistical characteristics on an unswept wing are not constant along the streamwise direction. However, historical studies of roughness on iced airfoils performed in the NASA Icing Research Tunnel (IRT) at NASA Glenn Research Center employed image analysis approaches to create parametric representations of ice roughness element development over time. Because of the parametric descriptions and the limitations of the surface characterizations, ice roughness is often treated in analytical approaches and computational models as having constant parametric properties over the entire ice accretion area.
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
2015-01-2109
Rodrigo Domingos, Daniel Silva
This paper outlines a three-dimensional computer model named AIPAC suitable for bleed-air ice protection system parametric studies in support of system design and optimization. This 3D simulation code was derived from HASPAC, which is a 2D anti-icing model developed at Wichita State University in 2010. AIPAC is based on the Finite Volumes Method and, similarly to HASPAC, combines a commercial Navier-Stokes flow solver with a Messinger model based thermodynamic analysis that applies internal and external flows heat transfer coefficients, pressure distribution, wall shear stress, etc, to compute wing leading edge skin temperatures, 3D runback flow distribution, and the location, extent and rate of icing. In addition, AIPAC was built using a transient formulation and with the capability of extruding a 3D surface mesh into a volumetric domain, so that “single-shot” ice shapes can be predicted (a more accurate multiple-step ice growth methodology is currently being developed).
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
2015-01-2147
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
2015-01-2118
Sergey Alekseyenko, Michael Sinapius, Martin Schulz, Oleksandr Prykhodko
In spite of wide theoretical and experimental studies of icing problem that have been held up to recent times, nevertheless, the most dangerous flights regimes as in the presence of supercooled large droplets or in supercooled rain remain studied not enough. Also the range of parameters that corresponds to the exploitation modes of aircrafts with relatively small heights and speeds of flight like airplanes of small aviation, helicopters, UAV etc. because of the complexity of the icing processes are still not covered. The aim of this work is to answer the next question: which an actual process of interaction of supercooled large water droplets with growing ice surface at small speeds of flight and which physics of falling moisture freezing process on the icing surface is. Thus, the work presents the results of experiments conducted in order to obtain the photographic data on how the interaction between the supercooled water droplets and the icing aerodynamic surface occurs.
2015-06-15
Technical Paper
2015-01-2081
Hossein Habibi, Graham Edwards, Liang Cheng, Haitao Zheng, Adam Marks, Vassilios Kappatos, Cem Selcuk, Tat-Hean Gan
Wind turbines mounted on cold climate sites are subject to icing which could significantly influence the performance of turbine blades for harvesting wind energy. To alleviate this problem, a number of techniques have been developed and tested. The currently used methods are surface coating, antifreeze chemicals, electrical resistance heating, hot air circulation, pulse electrothermal de-icing, manual chip-off, etc. Almost all thermal de-ice methods demand a high level of power to operate. Also, the high temperature induced to the blade by the thermal techniques may pose a risk for the integrity of composite blades. A relatively new strategy used for ice protection systems is ultrasonic guided waves (vibrations of very short length wave) on which a few research projects have been recently accomplished. This method is well known for non-destructive testing applications in which the waves typically propagate between 20 kHz and 100 kHz for long-range ultrasonic testing.
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
2015-01-2080
Roger J. Aubert
While the industry is making consistent progress in predicting aerodynamic performance impact from ice accretion on rotor blade and ability to reliably design thermal anti-icing and/or deicing protection systems, ice shedding, natural or induced, is trailing behind both in terms of understanding the physics of impact ice adhesion and cohesion, mechanical fracture and energy dissipation upon impact on airframe or rotor systems. It is only recently that attention dedicated to the understanding of impact ice shedding on rotors has increased. Reference 1 summarizes the mechanical properties of ice. However, more recent test results (Reference 2 and 3) showed different results. It was therefore concluded that a data base more representative of helicopter operation was necessary. It is the intent of this paper to summarize the differences in test results and provide additional considerations for analytical modeling of the ice shedding process on a rotor blade.
2015-06-15
Technical Paper
2015-01-2100
Yongsheng Lian, Yisen Guo
This paper investigated impingement of supercooled large droplets onto smooth solid surfaces to understand the mechanism of splashing and secondary droplets formation using a novel moment of fluid (MOF) method. Previous studies have established a splashing threshold, but the effect of ambient gas in liquid droplet splashing is not fully understood. Our numerical results of water droplet splashing with relatively low velocity were consistent with experimental results: splashing occurs at high pressure but not at low pressure. Our simulation revealed that a thin film was formed after the droplet contacted the solid surface. The thin film moved at a lower speed at the contact with the solid due to viscous effect while the film moved at a higher speed away from the solid. As a result, air was trapped under the film, making the film floating on the air. When the pressure was high, the air density was high hence the aerodynamic forces by the air on the thin film.
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
2015-01-2091
Ryosuke Hayashi
Icing phenomena have been studied since the middle of 1990s, and the numerical procedure for typical icing has been established. Recently, there are new problems of icing, which are SLD icing, ice crystal icing, and ice shedding phenomenon. The SLD and the ICI has been studied since 1990s. However, there are few researches on the ice shedding since the ice has many unknown physical parameters which are the density in atmosphere, the adhesion force between the wall and the accreted ice, the contact force between ice pieces and so on. Although existing icing models can simulate ice growth, these models do not have the capability to reproduce ice shedding. In the previous study, we developed an icing model that takes into account both ice growth and ice shedding. Furthermore, we validated the proposed ice shedding model through the comparison of numerical results and experimental data, which includes the flow rate loss due to ice growth and the flow rate recovery due to ice shedding.
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
2015-01-2122
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
2015-01-2120
Yong Han Yeong, Eric Loth, Jack Sokhey, Alexis Lambourne
Superhydrophobic coatings have shown promise in reducing ice adhesion on a surface. However, recent superhydrophobic ice adhesion studies were conducted at either ice accretion conditions that do not resemble aerospace icing conditions, or at low super-cooled droplet impact speeds (less than 10 m/s). Therefore, a detailed experiment was conducted to measure the ice adhesion strength of various superhydrophobic coatings in an icing wind tunnel at an air speed of 50 m/s and at a temperature of -15°C with a super-cooled icing cloud consisting of 20 µm droplets. The ice was accreted on 3 mm thick, 30 mm diameter discs and then removed by pressurized nitrogen through the access hole in a tensile direction for a measurement of the ice fracture energy. Results showed no relationship between coating wettability parameters (water contact and receding angles) with ice fracture energy but depicted a general increase in fracture energy with increasing surface auto-correlation lengths.
2015-06-15
Technical Paper
2015-01-2117
Miki Shimura
It is well known that SLD icing is very dangerous because it is more unpredictable than general icing caused by smaller droplets. In SLD conditions, extraordinary phenomenon occurs. For example, SLD largely deforms. Vargas et al. (2010) performed the experiments about the droplet deformation. In their experiments, it was confirmed that the droplet height increases and the droplet width decreases, as the droplets approach the leading edge of an airfoil Therefore, the assumption that a droplet behaves as a sphere is no longer valid. To predict the deformation and the breakup of a droplet, several mathematical models have been proposed. For example, Ibrahim et al. (1993) proposed a model for the droplet deformation and breakup (DDB) model. However, the DDB model has not found wide acceptance. Other models exist, in which the deformation is described with the change of drag coefficient.
2015-06-15
Technical Paper
2015-01-2129
Andrea Munzing, Stephane Catris
A lot of research work on icing scaling laws has been done during the last decades resulting in a today commonly accepted definition of similarity parameters and scaling laws. Those icing scaling laws have essentially been developed for fixed wing applications because airplane aerodynamic surfaces are too big to be tested in icing wind tunnels. This problem does not exist for helicopter blade profiles. However, the use of icing scaling laws is a very interesting feature in order to be able to predict ice shapes or icing performance penalty for a future helicopter still in development. Thanks to the long experience of Airbus Helicopters with icing tests a database of several real ice shapes on helicopter main and tail rotor blade sections is available. The comparison of the ice shapes obtained at the same icing similarity parameters allows the assessment of 2D icing scaling laws established for fixed wing aircrafts.
Viewing 1 to 30 of 104148