WorldWideScience

Sample records for finnairis toetavad aero

  1. Finnairi streik jätkub / Sirje Rank

    Index Scriptorium Estoniae

    Rank, Sirje, 1966-

    2006-01-01

    Lennufirma Finnair kabiinipersonal streikis firma plaani vastu palgata 500 töötajat oma Eesti tütarfirma Aero Airlines kaudu. Palgakõnelused lahendust ei leidnud. Lisa: Täna neli lendu. Vt. samas: Eesti Post kannatas streigi tõttu; Lemmi Kann. Reisijad üritasid Tallinnas pileteid ümber vahetada; Eesti stjuardessid kauplevad palgatõusu

  2. Finnairi streik jätkub / Sirje Rank

    Index Scriptorium Estoniae

    Rank, Sirje, 1966-

    2006-01-01

    Lennufirma Finnair kabiinipersonal streikis firma plaani vastu palgata 500 töötajat oma Eesti tütarfirma Aero Airlines kaudu. Palgakõnelused lahendust ei leidnud. Lisa: Täna neli lendu. Vt. samas: Eesti Post kannatas streigi tõttu; Lemmi Kann. Reisijad üritasid Tallinnas pileteid ümber vahetada; Eesti stjuardessid kauplevad palgatõusu

  3. Soomlaste Finnair sulges eile oma Eesti lennufirma / Lauri Linnamäe

    Index Scriptorium Estoniae

    Linnamäe, Lauri

    2008-01-01

    Finnairi Eesti tütarfirma Aero Airlines lõpetas oma lennud nii Tallinna-Helsingi vahel kui ka Soome siseliinidel, Eesti ja Soome vahelised lennud võtab üle Soome firma Finncomm Airlines. Lisa: Aero Airlines

  4. Soomlaste Finnair sulges eile oma Eesti lennufirma / Lauri Linnamäe

    Index Scriptorium Estoniae

    Linnamäe, Lauri

    2008-01-01

    Finnairi Eesti tütarfirma Aero Airlines lõpetas oma lennud nii Tallinna-Helsingi vahel kui ka Soome siseliinidel, Eesti ja Soome vahelised lennud võtab üle Soome firma Finncomm Airlines. Lisa: Aero Airlines

  5. Aero Fighter - 2D Gaming

    CERN Document Server

    Ahmed, Zeeshan

    2010-01-01

    Designing and developing quality based computer game is always a challenging task for developers. In this paper I briefly discuss aero fighting war game based on simple 2D gaming concepts and developed in C & C++ programming languages, using old bitmapping concepts. Going into the details of the game development, I discuss the designed strategies, flow of game and implemented prototype version of game, especially for beginners of game programming.

  6. The DAN-AERO MW Experiments

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Bak, Christian; Schmidt Paulsen, Uwe

    This report describes the DAN-AERO MW experiments carried out within a collaborative, three years research project between Risø DTU and the industrial partners LM Glasfiber, Siemens Wind Power, Vestas Wind Systems A/S and the utility company DONG Energy. The main objective of the project was to e......This report describes the DAN-AERO MW experiments carried out within a collaborative, three years research project between Risø DTU and the industrial partners LM Glasfiber, Siemens Wind Power, Vestas Wind Systems A/S and the utility company DONG Energy. The main objective of the project...... in a wind tunnel and the unsteady 3D flow conditions on a rotor. The different transition characteristics might explain some of the differences between the 2D and 3D airfoil data and the experiments have been set up to provide data on this subject. The overall experimental approach has been to carry out...

  7. AeroValve Experimental Test Data Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Noakes, Mark W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-09-01

    This report documents the collection of experimental test data and presents performance characteristics for the AeroValve brand prototype pneumatic bidirectional solenoid valves tested at the Oak Ridge National Laboratory (ORNL) in July/August 2014 as part of a validation of AeroValve energy efficiency claims. The test stand and control programs were provided by AeroValve. All raw data and processing are included in the report attachments.

  8. Aero-acoustic modeling using large eddy simulation

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Sørensen, Jens Nørkær

    2007-01-01

    The splitting technique for aero-acoustic computations is extended to simulate three-dimensional flow and acoustic waves from airfoils. The aero-acoustic model is coupled to a sub-grid-scale turbulence model for Large-Eddy Simulations. In the first test case, the model is applied to compute laminar...

  9. National aero-space plane: Flight mechanics

    Science.gov (United States)

    Mciver, Duncan E.; Morrell, Frederick R.

    1990-01-01

    The current status and plans of the U.S. National Aero-Space Plane (NASP) program are reviewed. The goal of the program is to develop technology for single stage, hypersonic vehicles which use airbreathing propulsion to fly directly to orbit. The program features an X-30 flight research vehicle to explore altitude-speed regimes not amenable to ground testing. The decision to build the X-30 is now scheduled for 1993, with the first flight in the late 1990's. The flight mechanics, controls, flight management, and flight test considerations for the X-30 are discussed.

  10. Aero and vibroacoustics of automotive turbochargers

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen-Schaefer, Hung [Bosch Mahle Turbo Systems GmbH, Stuttgart (Germany)

    2013-02-01

    First book about the aeroacoustics of automotive turbochargers. Author of the book ''Rotordynamics of Automotive Turbochargers'', Springer, 2012. Written by an R and D expert in the turbocharger industry. Aero and Vibroacoustics of Automotive Turbochargers is a topic involving aspects from the working fields of thermodynamics of turbomachinery, aerodynamics, rotordynamics, and noise propagation computation. In this broadly interdisciplinary subject, thermodynamics of turbomachinery is used to design the turbocharger and to determine its operating conditions. Aerodynamics is needed to study the compressor flow dynamics and flow instabilities of rotating stall and surge, which can produce growling and whining-type noises. Rotordynamics is necessary to study rotor unbalance and self-excited oil-whirl instabilities, which lead to whistling and constant tone-type noises in rotating floating oil-film type bearings. For the special case of turbochargers using ball bearings, some high-order harmonic and wear noises also manifest in the rotor operating range. Lastly, noise propagation computation, based on Lighthill's analogy, is required to investigate airborne noises produced by turbochargers in passenger vehicles. The content of this book is intended for advanced undergraduates, graduates in mechanical engineering, research scientists and practicing engineers who want to better understand the interactions between these working fields and the resulting impact on the interesting topic of Aero and Vibroacoustics of Automotive Turbochargers.

  11. Aero and vibroacoustics of automotive turbochargers

    CERN Document Server

    Nguyen-Schäfer, Hung

    2013-01-01

    Aero and Vibroacoustics of Automotive Turbochargers is a topic involving aspects from the working fields of thermodynamics of turbomachinery, aerodynamics, rotordynamics, and noise propagation computation.   In this broadly interdisciplinary subject, thermodynamics of turbomachinery is used to design the turbocharger and to determine its operating conditions.  Aerodynamics is needed to study the compressor flow dynamics and flow instabilities of rotating stall and surge, which can produce growling and whining-type noises. Rotordynamics is necessary to study rotor unbalance and self-excited oil-whirl instabilities, which lead to whistling and constant tone-type noises in rotating floating oil-film type bearings. For the special case of turbochargers using ball bearings, some high-order harmonic and wear noises also manifest in the rotor operating range. Lastly, noise propagation computation, based on Lighthill’s analogy, is required to investigate airborne noises produced by turbochargers in passenger vehi...

  12. Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  13. MEMS and mil/aero: technology push and market pull

    Science.gov (United States)

    Clifford, Thomas H.

    2001-04-01

    MEMS offers attractive solutions to high-density fluidics, inertial, optical, switching and other demanding military/aerospace (mil/aero) challenges. However, full acceptance must confront the realities of production-scale producibility, verifiability, testability, survivability, as well as long-term reliability. Data on these `..ilities' are crucial, and are central in funding and deployment decisions. Similarly, mil/aero users must highlight specific missions, environmental exposures, and procurement issues, as well as the quirks of its designers. These issues are particularly challenging in MEMS, because of the laws of physics and business economics, as well as the risks of deploying leading-edge technology into no-fail applications. This paper highlights mil/aero requirements, and suggests reliability/qualification protocols, to guide development effort and to reassure mil/aero users that MEMS labs are mindful of the necessary realities.

  14. Aero-Assisted Spacecraft Missions Using Hypersonic Waverider Aeroshells

    Science.gov (United States)

    Knittel, Jeremy

    This work examines the use of high-lift, low drag vehicles which perform orbital transfers within a planet's atmosphere to reduce propulsive requirements. For the foreseeable future, spacecraft mission design will include the objective of limiting the mass of fuel required. One means of accomplishing this is using aerodynamics as a supplemental force, with what is termed an aero-assist maneuver. Further, the use of a lifting body enables a mission designer to explore candidate trajectory types wholly unavailable to non-lifting analogs. Examples include missions to outer planets by way of an aero-gravity assist, aero-assisted plane change, aero-capture, and steady atmospheric periapsis probing missions. Engineering level models are created in order to simulate both atmospheric and extra-atmospheric space flight. Each mission is parameterized using discrete variables which control multiple areas of design. This work combines the areas of hypersonic aerodynamics, re-entry aerothermodynamics, spacecraft orbital mechanics, and vehicle shape optimization. In particular, emphasis is given to the parametric design of vehicles known as "waveriders" which are inversely designed from known shock flowfields. An entirely novel means of generating a class of waveriders known as "starbodies" is presented. A complete analysis is performed of asymmetric starbody forms and compared to a better understood parameterization, "osculating cone" waveriders. This analysis includes characterization of stability behavior, a critical discipline within hypersonic flight. It is shown that asymmetric starbodies have significant stability improvement with only a 10% reduction in the lift-to-drag ratio. By combining the optimization of both the shape of the vehicle and the trajectory it flies, much is learned about the benefit that can be expected from lifting aero-assist missions. While previous studies have conceptually proven the viability, this work provides thorough quantification of the

  15. Aero-Thermo-Dynamic Mass Analysis

    Science.gov (United States)

    Shiba, Kota; Yoshikawa, Genki

    2016-07-01

    Each gas molecule has its own molecular weight, while such a microscopic characteristic is generally inaccessible, and thus, it is measured indirectly through e.g. ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events into macroscopic phenomena. It is confirmed that this approach can provide molecular weight of virtually any gas or vaporizable liquid sample in real-time without ionization. Demonstrations through analytical calculations, numerical simulations, and experiments verify the validity and versatility of the novel mass analysis realized by a simple setup with a flexible object (e.g. with a bare cantilever and even with a business card) placed in a laminar jet. Owing to its unique and simple working principle, this aero-thermo-dynamic mass analysis (AMA) can be integrated into various analytical devices, production lines, and consumer mobile platforms, opening new chapters in aerodynamics, thermodynamics, mechanics, and mass analysis.

  16. Rotarid toetavad noorte haridust / Rita Loel

    Index Scriptorium Estoniae

    Loel, Rita, 1966-2012

    2009-01-01

    USA Minnesota Rotchesteri Rotary klubi liige, Kuressaares sündinud Ingrid Vaga Neel, külastas ametikooli UPA õpilaskodu, Kuressaare Gümnaasiumit ja huvikeskust, et vaadata kuidas kahe maa Rotary klubide ühisprojekt on töösse läinud

  17. Rotarid toetavad noorte haridust / Rita Loel

    Index Scriptorium Estoniae

    Loel, Rita, 1966-2012

    2009-01-01

    USA Minnesota Rotchesteri Rotary klubi liige, Kuressaares sündinud Ingrid Vaga Neel, külastas ametikooli UPA õpilaskodu, Kuressaare Gümnaasiumit ja huvikeskust, et vaadata kuidas kahe maa Rotary klubide ühisprojekt on töösse läinud

  18. Experimental Technique of Titanium Fire in Aero-engine

    Directory of Open Access Journals (Sweden)

    MI Guangbao

    2016-06-01

    Full Text Available Titanium fire is the typical catastrophic fault in the aero-engine. Aiming at the urgent demand for experimental technique of titanium fire from advanced high thrust-weight ratio aero-engine, the combustion technology and theory of titanium alloy based on friction oxygen concentration method (FOC were systematically studied. The evaluation method of fireproof property and the friction ignition model were built, and the fireproof mechanism was illustrated. By generalizing recent progress in experimental technique of titanium fire from three levels, including evolutionary rule, mechanism and prevention and control technology, the ideas and directions of experimental technique associated with the application research of titanium fire in the future were proposed, namely overall evaluation of fireproof property close to air flow environment of the aero-engine, prediction model of fireproof property and experimental verification of fireproof technique under the air flow environment of aero-engine. It is necessary to establish the prevention system of titanium fire in aero-engine, which contributes to the realization of "full titanium" in compressor and to the increase of high thrust-weight ratio.

  19. Aero-Optic Evaluation Center (AOEC), Large Energy National Shock (LENS) Tunnels I & II

    Data.gov (United States)

    Federal Laboratory Consortium — The AOEC facility provides world class capability for aero-thermo-chemical, aerooptics and aero-propulsion testing in the Mach number range from 2.5 to 15 using the...

  20. SIERRA/Aero User Manual Version 4.44

    Energy Technology Data Exchange (ETDEWEB)

    Sierra Thermal/Fluid Team

    2017-04-01

    SIERRA/Aero is a compressible fluid dynamics program intended to solve a wide variety compressible fluid flows including transonic and hypersonic problems. This document describes the commands for assembling a fluid model for analysis with this module, henceforth referred to simply as Aero for brevity. Aero is an application developed using the SIERRA Toolkit (STK). The intent of STK is to provide a set of tools for handling common tasks that programmers encounter when developing a code for numerical simulation. For example, components of STK provide field allocation and management, and parallel input/output of field and mesh data. These services also allow the development of coupled mechanics analysis software for a massively parallel computing environment. In the definitions of the commands that follow, the term Real_Max denotes the largest floating point value that can be represented on a given computer. Int_Max is the largest such integer value.

  1. SIERRA/Aero Theory Manual Version 4.44

    Energy Technology Data Exchange (ETDEWEB)

    Sierra Thermal/Fluid Team

    2017-04-01

    SIERRA/Aero is a two and three dimensional, node-centered, edge-based finite volume code that approximates the compressible Navier-Stokes equations on unstructured meshes. It is applicable to inviscid and high Reynolds number laminar and turbulent flows. Currently, two classes of turbulence models are provided: Reynolds Averaged Navier-Stokes (RANS) and hybrid methods such as Detached Eddy Simulation (DES). Large Eddy Simulation (LES) models are currently under development. The gas may be modeled either as ideal, or as a non-equilibrium, chemically reacting mixture of ideal gases. This document describes the mathematical models contained in the code, as well as certain implementation details. First, the governing equations are presented, followed by a description of the spatial discretization. Next, the time discretization is described, and finally the boundary conditions. Throughout the document, SIERRA/ Aero is referred to simply as Aero for brevity.

  2. Vehicle Health Management Communications Requirements for AeroMACS

    Science.gov (United States)

    Kerczewski, Robert J.; Clements, Donna J.; Apaza, Rafael D.

    2012-01-01

    As the development of standards for the aeronautical mobile airport communications system (AeroMACS) progresses, the process of identifying and quantifying appropriate uses for the system is progressing. In addition to defining important elements of AeroMACS standards, indentifying the systems uses impacts AeroMACS bandwidth requirements. Although an initial 59 MHz spectrum allocation for AeroMACS was established in 2007, the allocation may be inadequate; studies have indicated that 100 MHz or more of spectrum may be required to support airport surface communications. Hence additional spectrum allocations have been proposed. Vehicle health management (VHM) systems, which can produce large volumes of vehicle health data, were not considered in the original bandwidth requirements analyses, and are therefore of interest in supporting proposals for additional AeroMACS spectrum. VHM systems are an emerging development in air vehicle safety, and preliminary estimates of the amount of data that will be produced and transmitted off an aircraft, both in flight and on the ground, have been prepared based on estimates of data produced by on-board vehicle health sensors and initial concepts of data processing approaches. This allowed an initial estimate of VHM data transmission requirements for the airport surface. More recently, vehicle-level systems designed to process and analyze VHM data and draw conclusions on the current state of vehicle health have been undergoing testing and evaluation. These systems make use of vehicle system data that is mostly different from VHM data considered previously for airport surface transmission, and produce processed system outputs that will be also need to be archived, thus generating additional data load for AeroMACS. This paper provides an analysis of airport surface data transmission requirements resulting from the vehicle level reasoning systems, within the context of overall VHM data requirements.

  3. Vortex-Based Aero- and Hydrodynamic Estimation

    Science.gov (United States)

    Hemati, Maziar Sam

    Flow control strategies often require knowledge of unmeasurable quantities, thus presenting a need to reconstruct flow states from measurable ones. In this thesis, the modeling, simulation, and estimator design aspects of flow reconstruction are considered. First, a vortex-based aero- and hydrodynamic estimation paradigm is developed to design a wake sensing algorithm for aircraft formation flight missions. The method assimilates wing distributed pressure measurements with a vortex-based wake model to better predict the state of the flow. The study compares Kalman-type algorithms with particle filtering algorithms, demonstrating that the vortex nonlinearities require particle filters to yield adequate performance. Furthermore, the observability structure of the wake is shown to have a negative impact on filter performance regardless of the algorithm applied. It is demonstrated that relative motions can alleviate the filter divergence issues associated with this observability structure. In addition to estimator development, the dissertation addresses the need for an efficient unsteady multi-body aerodynamics testbed for estimator and controller validation studies. A pure vortex particle implementation of a vortex panel-particle method is developed to satisfy this need. The numerical method is demonstrated on the impulsive startup of a flat plate as well as the impulsive startup of a multi-wing formation. It is clear, from these validation studies, that the method is able to accommodate the unsteady wake effects that arise in formation flight missions. Lastly, successful vortex-based estimation is highly dependent on the reliability of the low-order vortex model used in representing the flow of interest. The present treatise establishes a systematic framework for vortex model improvement, grounded in optimal control theory and the calculus of variations. By minimizing model predicted errors with respect to empirical data, the shortcomings of the baseline vortex model

  4. Global dust model intercomparison in AeroCom phase I

    NARCIS (Netherlands)

    Huneeus, N.; Schulz, M.; Balkanski, Y.; Griesfeller, J.; Krol, M.C.

    2011-01-01

    This study presents the results of a broad intercomparison of a total of 15 global aerosol models within the AeroCom project. Each model is compared to observations related to desert dust aerosols, their direct radiative effect, and their impact on the biogeochemical cycle, i.e., aerosol optical dep

  5. Generic methods for aero-engine exhaust emission prediction

    NARCIS (Netherlands)

    Shakariyants, S.A.

    2008-01-01

    In the thesis, generic methods have been developed for aero-engine combustor performance, combustion chemistry, as well as airplane aerodynamics, airplane and engine performance. These methods specifically aim to support diverse emission prediction studies coupled with airplane and engine simulation

  6. Integrated evaluation of the geology, aero gamma spectrometry and aero magnetometry of the Sul-Riograndense Shield, southernmost Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Leo A.; Savian, Jairo F., E-mail: leo.hartmann@ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRS), Porto Alegre, RS (Brazil). Instituto de Geociencias; Lopes, William R. [Servico Geologico do Brasil (CPRM), Porto Alegre, RS (Brazil). Gerencia de Geologia e Mineracao

    2016-03-15

    An integrated evaluation of geology, aero gamma spectrometry and aero magnetometry of the Sul-Riograndense Shield is permitted by the advanced stage of understanding of the geology and geochronology of the southern Brazilian Shield and a 2010 airborne geophysical survey. Gamma rays are registered from the rocks near the surface and thus describe the distribution of major units in the shield, such as the Pelotas batholith, the juvenile São Gabriel terrane, the granulite-amphibolite facies Taquarembo terrane and the numerous granite intrusions in the foreland. Major structures are also observed, e.g., the Dorsal de Cangucu shear. Magnetic signals register near surface crustal compositions (analytic signal) and total crust composition (total magnetic signal), so their variation as measured indicates either shallow or whole crustal structures. The Cacapava shear is outstanding on the images as is the magnetic low along the N-S central portion of the shield. These integrated observations lead to the deepening of the understanding of the largest and even detailed structures of the Sul-Riograndense Shield, some to be correlated to field geology in future studies. Most significant is the presence of different provinces and their limits depending on the method used for data acquisition - geology, aero gamma spectrometry or aero magnetometry. (author)

  7. XCOR AeroSpace: Providing Low Cost Access to Space

    Science.gov (United States)

    2009-02-01

    transport anywhere in world and fly (6-8000 ft of runway needed) • Fly unpredictable times, multiple times per day, cheaply! • Small Satellite Launch...programs • Avoiding ONE failure or substantial program slip pays for the whole Lynx program many -fold UPDATE - Progress In Last 30 Days 7 •Further...troops released from delivery system – TPS built in to suits or MOOSE -like solo system – Aero deceleration high in atmosphere, GPS-guided chutes

  8. Net-Shape Processing Applied to Aero-Engine Components

    Science.gov (United States)

    2006-05-01

    sustainable in the aero-engine business as the cost of key materials such as titanium and nickel alloys is escalating, fuelled by the seemingly...have deformed to consolidate the powder is removed by rough machining and/or pickling to reveal the net-shape component. The key to producing net...being relatively expensive in terms of cost and environmental impact, mainly due to the cost of machining the mild steel tooling and having to pickle

  9. Air Force Research in Aero Propulsion Technology (AFRAPT)

    Science.gov (United States)

    1990-09-27

    Aero Propulsion Technology (AFRAPT) 12. PERSONAL AUTHOR(S) Profs. J. Dugundji , A. Epstein, M. Giles, E. Greitzer, M. Martinez-Sanchez, flr r T~ri 13a...Professor of Aeronautics and Astronautics Director, Gas Turbine Laboratory John Dugundji Professor, Dept. of Aeronautics and Astronautics Alan H. Epstein...Professor J. Dugundji /Professor E.M. Greitzer Project: Compressor Stabilization Through Structural Feedback Trainee: Dana Lindquist Advisor: Professor M.B

  10. Experimental Study on Aero Conductivity of Porous Media

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To study the variation pattern of aero conductivity of different porous media under low pressure conditions, three kinds of media are selected.These include sandy clay loam, fine sand, and medium sand, and air as fluid to conduct soil column ventilation tests.Pressure at both ends of the columns is measured under different ventilation flow rates during testing.The test results show that the aero conductivity, solved by Darcy's law, is not a constant.It is a variable, which increases first when air flow velocity is less than 0.258 7 cm/ s for sandy clay loam, 0.637 3 cm/s for fine sand and then decreases when air flow velocity is bigger than that with the increase of the ventilation flow rate when the medium is determined.By analyzing various factors that influence the flow resistance, the reasons for variation in aero conductivity are found as follows: first, the change of pore structure results in better ventilation; second, the relationship between pressure head loss and air flow velocity is nonlinear, and it is beyond the condition of the laminar flow domain to which Darcy's law can be applied, when the air flow rate increases to a certain value and the flow velocity is in the transition range to turbulent flow.

  11. Failure Analysis towards Reliable Performance of Aero-Engines

    Directory of Open Access Journals (Sweden)

    T. Jayakumar

    1999-10-01

    Full Text Available Aero-engines are critical components whose reliable performance decides the primary safety of anaircrafthelicopter. This is met by rigorous maintenance schedule with periodic inspection/nondestructive testingof various engine components. In spite of these measures, failure of areo-engines do occur rather frequentlyin comparison to failure of other components. Systematic failure analysis helps one to identify root causeof the failure, thus enabling remedial measures to prevent recurrence of such failures. Turbine blades madeof nickel or cobalt-based alloys are used in aero-engines. These blades are subjected to complex loadingconditions at elevated temperatures. The main causes of failure of blades are attributed to creep, thermalfatigue and hot corrosion. Premature failure of blades in the combustion zone was reported in one of theaero-engines. The engine had both the compressor and the free-turbine in a common shaft. Detailedfailure analysis revealed the presence of creep voids in the blades that failed. Failure of turbine bladeswas also detected in another aero-engine operating in a coastal environment. In this failure, the protectivecoating on the blades was cracked at many locations. Grain boundary spikes were observed on these locations.The primary cause of this failure was the hot corrosion followed by creep damage

  12. Maintenance Decision Based on Data Fusion of Aero Engines

    Directory of Open Access Journals (Sweden)

    Huawei Wang

    2013-01-01

    Full Text Available Maintenance has gained a great importance as a support function for ensuring aero engine reliability and availability. Cost-effectiveness and risk control are two basic criteria for accurate maintenance. Given that aero engines have much condition monitoring data, this paper presents a new condition-based maintenance decision system that employs data fusion for improving accuracy of reliability evaluation. Bayesian linear model has been applied, so that the performance degradation evaluation of aero engines could be realized. A reliability evaluation model has been presented based on gamma process, which achieves the accurate evaluation by information fusion. In reliability evaluation model, the shape parameter is estimated by the performance degradation evaluation result, and the scale parameter is estimated by failure, inspection, and repair information. What is more, with such reliability evaluation as input variables and by using particle swarm optimization (PSO, a stochastic optimization of maintenance decision for aircraft engines has been presented, in which the effectiveness and the accuracy are demonstrated by a numerical example.

  13. 78 FR 56589 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Airplanes

    Science.gov (United States)

    2013-09-13

    .... Request To Change Compliance Time From Hours Time-in-Service (TIS) to Landings Carlo Cardu of PIAGGIO AERO... Change the Requirement To Replace the Main Landing Gear (MLG) Lever Hinge Fitting (LHF) Carlo Cardu of... Clarify Inspection Requirements for Newly Installed MLG Carlo Cardu of PIAGGIO AERO INDUSTRIES...

  14. The Physics of Boundary-Layer Aero-Optic Effects

    Science.gov (United States)

    2012-09-01

    index-of refraction in turn depends on the media density, ρ, via a Gladstone -Dale relation, [1], ’)1( nKnK GDGD =−=ρ , where KGD is a Gladstone -Dale...6. References [1] Gladstone , J. H., Dale, T. P. 1863 “Researches on the Refraction, Dispersion, and Sensitiveness of Liquids”, Philosophical...AIAA J, 7 9 ( 1969 ), pp. 1737–1743. [9] R.J. Hugo and E.J. Jumper, ”Applicability of the Aero-Optic Linking Equation to a Highly Coherent

  15. Aero-acoustic noise of wind turbines. Noise prediction models

    Energy Technology Data Exchange (ETDEWEB)

    Maribo Pedersen, B. [ed.

    1997-12-31

    Semi-empirical and CAA (Computational AeroAcoustics) noise prediction techniques are the subject of this expert meeting. The meeting presents and discusses models and methods. The meeting may provide answers to the following questions: What Noise sources are the most important? How are the sources best modeled? What needs to be done to do better predictions? Does it boil down to correct prediction of the unsteady aerodynamics around the rotor? Or is the difficult part to convert the aerodynamics into acoustics? (LN)

  16. Interference Analysis Status and Plans for Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Kerczewski, Robert J.; Wilson, Jeffrey D.

    2010-01-01

    Interference issues related to the operation of an aeronautical mobile airport communications system (AeroMACS) in the C-Band (specifically 5091-5150 MHz) is being investigated. The issue of primary interest is co-channel interference from AeroMACS into mobile-satellite system (MSS) feeder uplinks. The effort is focusing on establishing practical limits on AeroMACS transmissions from airports so that the threshold of interference into MSS is not exceeded. The analyses are being performed with the software package Visualyse Professional, developed by Transfinite Systems Limited. Results with omni-directional antennas and plans to extend the models to represent AeroMACS more accurately will be presented. These models should enable realistic analyses of emerging AeroMACS designs to be developed from NASA Test Bed, RTCA 223, and European results.

  17. An experimental study of aero-optical aberration and dithering of supersonic mixing layer via BOS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The optical performance of supersonic mixing layer is heavily deteriorated by the aero-optical aberration and dithering of coherent structures, but current measuring methods limit the spatiotemporal resolution in relevant studies. A high resolution whole-field aero-optical aberration and dithering measuring method based on the Background Orient Schlieren (BOS) technique was studied. The systematic structure, sensitivity and resolution of BOS are analyzed in this paper. The aero-optical aberration and dithering of streamwise structures in supersonic mixing layers were quantificationally studied with BOS. The aberration field of spanwise structures revealed the ribbon-like aberration structures, which heavily restrict the optical performance of a mixing layer. The quantifications of aero-optical aberration and dithering are very important in studying aero-optical performance of supersonic mixing layer.

  18. Optimization of Heat Exchangers for Intercooled Recuperated Aero Engines

    Directory of Open Access Journals (Sweden)

    Dimitrios Misirlis

    2017-03-01

    Full Text Available In the framework of the European research project LEMCOTEC, a section was devoted to the further optimization of the recuperation system of the Intercooled Recuperated Aero engine (IRA engine concept, of MTU Aero Engines AG. This concept is based on an advanced thermodynamic cycle combining both intercooling and recuperation. The present work is focused only on the recuperation process. This is carried out through a system of heat exchangers mounted inside the hot-gas exhaust nozzle, providing fuel economy and reduced pollutant emissions. The optimization of the recuperation system was performed using computational fluid dynamics (CFD computations, experimental measurements and thermodynamic cycle analysis for a wide range of engine operating conditions. A customized numerical tool was developed based on an advanced porosity model approach. The heat exchangers were modeled as porous media of predefined heat transfer and pressure loss behaviour and could also incorporate major and critical heat exchanger design decisions in the CFD computations. The optimization resulted in two completely new innovative heat exchanger concepts, named as CORN (COnical Recuperative Nozzle and STARTREC (STraight AnnulaR Thermal RECuperator, which provided significant benefits in terms of fuel consumption, pollutants emission and weight reduction compared to more conventional heat exchanger designs, thus proving that further optimization potential for this technology exists.

  19. Overview of additive manufacturing activities at MTU aero engines

    Science.gov (United States)

    Bamberg, Joachim; Dusel, Karl-Heinz; Satzger, Wilhelm

    2015-03-01

    Additive Manufacturing (AM) is a promising technology to produce parts easily and effectively, just by using metallic powder or wire as starting material and a sophisticated melting process. In contrast to milling or turning technologies complex shaped and hollow parts can be built up in one step. That reduces the production costs and allows the implementation of complete new 3D designs. Therefore AM is also of great interest for aerospace and aero engine industry. MTU Aero Engines has focused its AM activities to the selective laser melting technique (SLM). This technique uses metallic powder and a laser for melting and building up the part layer by layer. It is shown which lead part was selected for AM and how the first production line was established. A special focus is set on the quality assurance of the selective laser melting process. In addition to standard non-destructive inspection techniques a new online monitoring tool was developed and integrated into the SLM machines. The basics of this technique is presented.

  20. Fuzzy Computing for Control of Aero Gas Turbine Engines .

    Directory of Open Access Journals (Sweden)

    S. R. Balakrishnan

    1994-10-01

    Full Text Available Many methods, techniques and procedures available for designing the control system of plants and processes, are applied only after knowing accurately the plant or process to be controlled. However, in some complex situations where plants/processes cannot be accurately modelled, and especially where their control has human interaction, controller design may not be completely satisfactory. In such cases, it has been found that control decisions can be made on the basis of heuristic/linguistic measures or fuzzy algorithms. Fuzzy set principles have been used in controlling various plants/processes ranging from a laboratory steam engine to an autopilot, including an aero gas turbine engine engine for which the response of the engine speed for a fuzzy input of fuel flow has been studied. In this paper, certain stipulations and logic are suggested for the control of the total gas turbine engine. A case study of a single spool aero gas turbine engine with one of its state variables varied by heuristic logic is presented.

  1. Predicting Cavitation on Marine and Hydrokinetic Turbine Blades with AeroDyn V15.04

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Robynne [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-14

    Cavitation is an important consideration in the design of marine and hydrokinetic (MHK) turbines. The National Renewable Energy Laboratory's AeroDyn performance code was originally developed for horizontal-axis wind turbines and did not have the capability to predict cavitation inception. Therefore, AeroDyn has been updated to include the ability to predict cavitation on MHK turbines based on user-specified vapor pressure and submerged depth. This report outlines a verification of the AeroDyn V15.04 performance code for MHK turbines through a comparison to publicly available performance data.

  2. Aero-Acoustic Moldeling using Large Eddy Simulation

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Sørensen, Jens Nørkær

    2008-01-01

    The flow-acoustic splitting technique for aero-acoustic computations is extended to simulate the propagation of acoustic waves generated by three-dimensional turbulent flows. In the flow part, a sub-grid-scale turbulence model (the mixed model) is employed for Large-Eddy Simulations. The obtained...... instantaneous flow solution is employed as input for the acoustic part. At low Mach numbers the differences in scales and propagation speed between the flow and the acoustic field are quite large, hence different meshes and time-steps can be utilized for the two parts. The model is applied to compute flows past...... characteristics for angles of attack up to stall. For the acoustic solutions, predicted noise spectra are validated quantitatively against the experimental data of Brook et al. A parametrical study of the noise pattern for flows at angles of attack between 4 deg and 12 deg shows that the noise level is small...

  3. AERO-BACTERIOLOGICAL STUDY OF VEGETABLES MARKET AT JABALPUR

    Directory of Open Access Journals (Sweden)

    A. K. Pathak ، K. S. Verma

    2009-07-01

    Full Text Available Urban and rural vegetable markets of India characterized by mass activity with a little sanitary measure are responsible for generation of higher quantity of aerosols containing biotic and abiotic components. The aerosols generated in due course of mechanical disturbance, contain many organic compounds enable to sensitize vital respiratory organs of local inhabitants. Inhalation of airborne microorganisms can expose workers to risks from infection, toxicosis and allergy. The presence of non-spore forming gram-negative bacteria in air due to the mechanical areosolization indicates higher rate of dissemination of pollutants in these occupation associated areas. The present aero-bacteriological investigation included enumeration, identification and numerical analysis of different types of culturable airborne bacteria with inhalable fraction of gram-negative bacteria in the vegetable market of the city of Jabalpur, in order to measure the degree of aerobiopollution for this environment. The aero-bacteriological sampling has been done fortnightly for a period of one year. Samples were cultured based on standard methods. The survey revealed that in this type of atmosphere, environmental factors were responsible for the persistence of airborne bacteria with variable effects. The major contributors for aerosol generation were other mechanical activities, since this site is classified under human activity-enriched and highly trafficked site. The bioload of this atmosphere was recorded as high as 2.9 x 103 bacterial carrying particles per cubic meter during winter, dominated by both inhalable and non inhalable fractions of gram-negative bacteria. In summer, soil-borne bacteria were reported dominant in the air. High humidity and low temperature were the major factors for dissemination and distribution of gram-negative bacilli. A regression model with upto 43% variance was prepared in order to predict the bioload for this atmosphere in relation to

  4. [Flight nurses' comprehension about their role in the multiprofesional team of aero-medical transport].

    Science.gov (United States)

    Scuissiato, Dayane Reinhardt; Boffi, Letícia Valois; da Rocha, Roseline da Rocha; Montezeli, Juliana Helena; Bordin, Michelle Taverna; Peres, Aida Maris

    2012-01-01

    This is a descriptive qualitative research which aimed at identifying the flight nurses' comprehension by about their role in the aero-medical multiprofesional team. A semi-structured interview was carried out with eight flight nurses from Curitiba-PR, from June to August 2009. The speeches were analyzed by the content analysis, from which three categories emerged. The first describes the responsibilities of the flight nurses as managers of the aero-medical mission, planning for before, during and after the transport, what includes the aircraft check-list and knowledge of the patient's case. The second category deals with aspects of these professionals as care providers to the aero-transferred patient. The third describes communication and team-work as fundamental requirements for flight nurses. It was concluded that the nurse in aero-medical team mixes management and caring in his/her professional practice by the use of specific competences.

  5. Advanced High Temperature Adhesives for Thermally Stable Aero-assist Technologies Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aero-assist technologies are used to control the velocity of exploration vehicles (EV) when entering earth or other planetary atmospheres. Since entry of EVs in...

  6. Aero-Engine Fault Diagnosis Using Improved Local Discriminant Bases and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Jianwei Cui

    2014-01-01

    Full Text Available This paper presents an effective approach for aero-engine fault diagnosis with focus on rub-impact, through combination of improved local discriminant bases (LDB with support vector machine (SVM. The improved LDB algorithm, using both the normalized energy difference and the relative entropy as quantification measures, is applied to choose the optimal set of orthogonal subspaces for wavelet packet transform- (WPT- based signal decomposition. Then two optimal sets of orthogonal subspaces have been obtained and the energy features extracted from those subspaces appearing in both sets will be selected as input to a SVM classifier to diagnose aero-engine faults. Experiment studies conducted on an aero-engine rub-impact test system have verified the effectiveness of the proposed approach for classifying working conditions of aero-engines.

  7. Integrated Reconfigurable Aero and Propulsion Control for Improved Flight Safety of Commercial Aircraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this project is to develop and test a novel innovative Integrated Reconfigurable Aero & Propulsion Control (IRAP) system that achieves...

  8. A SERIES OF UNCOMMON FOREIGN BODIES PRESENTING IN THE AERO-DIGESTIVE TRACT

    Directory of Open Access Journals (Sweden)

    Jitendra Singh

    2016-02-01

    Full Text Available Foreign body impacted in the aero-digestive tract is one of the earliest reported problems. Coins, buttons, marbles, crayons, parts of toys etc. are the most commonly ingested foreign bodies in children. Fish, meat and chicken bones, dentures, nails etc.the most common foreign bodies ingested by adultsWe report a series of unusual foreign body ingestion in aero-digestive tract and their management by endoscopic retrieval.

  9. Corin/Dorin: A WDM-Enabled Platform for Aero-Engine Control Systems

    OpenAIRE

    Xia, Ming; Moslehi, Behzad; Mukherjee, Biswanath; Behbahani, Alireza; Millar, Richard

    2008-01-01

    The Full Authority Digital Electronic Control (FADEC) centralized architecture has become the norm in aero-engine control systems. With a centralized system, changes are costly and complex [1]. The goal of this work is to develop the architectural design concept for a distributed supporting network called Coarse WDM Optical Ring Network (CORIN) appropriate for aero-engine performance monitoring. A CORIN features high bandwidth, reliability, modularity, scalability, flexibility, an...

  10. Fault Diagnosis of Demountable Disk-Drum Aero-Engine Rotor Using Customized Multiwavelet Method

    OpenAIRE

    Jinglong Chen; Yu Wang; Zhengjia He; Xiaodong Wang

    2015-01-01

    The demountable disk-drum aero-engine rotor is an important piece of equipment that greatly impacts the safe operation of aircraft. However, assembly looseness or crack fault has led to several unscheduled breakdowns and serious accidents. Thus, condition monitoring and fault diagnosis technique are required for identifying abnormal conditions. Customized ensemble multiwavelet method for aero-engine rotor condition identification, using measured vibration data, is developed in this paper. Fir...

  11. Aero-Thermal Calibration of the NASA Glenn Icing Research Tunnel (2012 Tests)

    Science.gov (United States)

    Pastor-Barsi, Christine; Allen, Arrington E.

    2013-01-01

    A full aero-thermal calibration of the NASA Glenn Icing Research Tunnel (IRT) was completed in 2012 following the major modifications to the facility that included replacement of the refrigeration plant and heat exchanger. The calibration test provided data used to fully document the aero-thermal flow quality in the IRT test section and to construct calibration curves for the operation of the IRT.

  12. Comparison of the dynamism of the cardial rate by different kind of the Aerobic dynamic kickbox and Aero-kickboxing

    OpenAIRE

    Matoušková, Lucie

    2007-01-01

    Title: Comparison of heart rate dynamics In Aerobic Dynamic K.ickboxing and Aero-kickboxing Goal: Assessment of heart rate dynamics In Aerobic Dynamic K.ickboxing and Aero- K.ickboxing Method: For evaluation of relations connected to performance of cardiovascular system of respective individuals questionnaires were used. During selected classes of Aerobic Dynamic K.ickboxing and Aero-kickboxing I have measured heart rate using sport testers. Collected data were analysed and graphically evalua...

  13. The DAN-AERO MW experiments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Aagaard Madsen, H.; Bak, C.; Schmidt Paulsen, U.; Gaunaa, M. (Risoe DTU, Roskilde (Denmark)); Fuglsang, P. (LM Glasfiber, Kolding (Denmark)); Romblad, J.; Olesen, N.A. (Vestas Wind Systems, Ringkoebing (Denmark)); Enevoldsen, P.; Laursen, J. (Siemens Wind Power, Ballerup (Denmark)); Jensen, Leo (DONG Energy, Fredericia (Denmark))

    2010-09-15

    This report describes the DAN-AERO MW experiments carried out within a collaborative, three years research project between Risoe DTU and the industrial partners LM Glasfiber, Siemens Wind Power, Vestas Wind Systems A/S and the utility company DONG Energy. The main objective of the project was to establish an experimental data base which can provide new insight into a number of fundamental aerodynamic and aero-acoustic issues, important for the design and operation of MW size turbines. The most important issue is the difference between airfoil characteristics measured under 2D, steady conditions in a wind tunnel and the unsteady 3D flow conditions on a rotor. The different transition characteristics might explain some of the differences between the 2D and 3D airfoil data and the experiments have been set up to provide data on this subject. The overall experimental approach has been to carry out a number of coordinated, innovative measurements on full scale MW size rotors as well as on airfoils for MW size turbines in wind tunnels. Shear and turbulence inflow characteristics were measured on a Siemens 3.6 MW turbine with a five hole pitot tube. Pressure and turbulent inflow characteristics were measured on a 2MW NM80 turbine with an 80 m rotor. One of the LM38.8 m blades on the rotor was replaced with a new LM38.8 m blade where instruments for surface pressure measurements at four radial sections were build into the blade during the blade production process. Additionally, the outmost section on the blade was further instrumented with around 50 microphones for high frequency surface pressure measurements. The surface pressure measurements have been correlated with inflow measurements from four five hole pitot tubes and two sensors for measuring the high frequency (50 Hz to10 kHz) contents of the inflow turbulence. In parallel, 2D wind tunnel measurements on common airfoils for wind turbine applications have been conducted in three different wind tunnels at Delft

  14. On the precision of aero-thermal simulations for TMT

    Science.gov (United States)

    Vogiatzis, Konstantinos; Thompson, Hugh

    2016-08-01

    Environmental effects on the Image Quality (IQ) of the Thirty Meter Telescope (TMT) are estimated by aero-thermal numerical simulations. These simulations utilize Computational Fluid Dynamics (CFD) to estimate, among others, thermal (dome and mirror) seeing as well as wind jitter and blur. As the design matures, guidance obtained from these numerical experiments can influence significant cost-performance trade-offs and even component survivability. The stochastic nature of environmental conditions results in the generation of a large computational solution matrix in order to statistically predict Observatory Performance. Moreover, the relative contribution of selected key subcomponents to IQ increases the parameter space and thus computational cost, while dictating a reduced prediction error bar. The current study presents the strategy followed to minimize prediction time and computational resources, the subsequent physical and numerical limitations and finally the approach to mitigate the issues experienced. In particular, the paper describes a mesh-independence study, the effect of interpolation of CFD results on the TMT IQ metric, and an analysis of the sensitivity of IQ to certain important heat sources and geometric features.

  15. Multidisciplinary Design Optimization on Conceptual Design of Aero-engine

    Science.gov (United States)

    Zhang, Xiao-bo; Wang, Zhan-xue; Zhou, Li; Liu, Zeng-wen

    2016-06-01

    In order to obtain better integrated performance of aero-engine during the conceptual design stage, multiple disciplines such as aerodynamics, structure, weight, and aircraft mission are required. Unfortunately, the couplings between these disciplines make it difficult to model or solve by conventional method. MDO (Multidisciplinary Design Optimization) methodology which can well deal with couplings of disciplines is considered to solve this coupled problem. Approximation method, optimization method, coordination method, and modeling method for MDO framework are deeply analyzed. For obtaining the more efficient MDO framework, an improved CSSO (Concurrent Subspace Optimization) strategy which is based on DOE (Design Of Experiment) and RSM (Response Surface Model) methods is proposed in this paper; and an improved DE (Differential Evolution) algorithm is recommended to solve the system-level and discipline-level optimization problems in MDO framework. The improved CSSO strategy and DE algorithm are evaluated by utilizing the numerical test problem. The result shows that the efficiency of improved methods proposed by this paper is significantly increased. The coupled problem of VCE (Variable Cycle Engine) conceptual design is solved by utilizing improved CSSO strategy, and the design parameter given by improved CSSO strategy is better than the original one. The integrated performance of VCE is significantly improved.

  16. Dynamic performance of an aero-assist spacecraft - AFE

    Science.gov (United States)

    Chang, Ho-Pen; French, Raymond A.

    1992-01-01

    Dynamic performance of the Aero-assist Flight Experiment (AFE) spacecraft was investigated using a high-fidelity 6-DOF simulation model. Baseline guidance logic, control logic, and a strapdown navigation system to be used on the AFE spacecraft are also modeled in the 6-DOF simulation. During the AFE mission, uncertainties in the environment and the spacecraft are described by an error space which includes both correlated and uncorrelated error sources. The principal error sources modeled in this study include navigation errors, initial state vector errors, atmospheric variations, aerodynamic uncertainties, center-of-gravity off-sets, and weight uncertainties. The impact of the perturbations on the spacecraft performance is investigated using Monte Carlo repetitive statistical techniques. During the Solid Rocket Motor (SRM) deorbit phase, a target flight path angle of -4.76 deg at entry interface (EI) offers very high probability of avoiding SRM casing skip-out from the atmosphere. Generally speaking, the baseline designs of the guidance, navigation, and control systems satisfy most of the science and mission requirements.

  17. Commercial Modular Aero-Propulsion System Simulation 40k

    Science.gov (United States)

    Guo, Ten-Huei; Lavelle, Thomas; Litt, Jonathan; Csank, Jeffrey; May, Ryan

    2011-01-01

    The Commercial Modular Aero-Propulsion System Simulation 40k (CMAPSS40k) software package is a nonlinear dynamic simulation of a 40,000-pound (approximately equals 178-kN) thrust class commercial turbofan engine, written in the MATLAB/Simulink environment. The model has been tuned to capture the behavior of flight test data, and is capable of running at any point in the flight envelope [up to 40,000 ft (approximately equals 12,200 m) and Mach 0.8]. In addition to the open-loop engine, the simulation includes a controller whose architecture is representative of that found in industry. C-MAPSS40k fills the need for an easy-to-use, realistic, transient simulation of a medium-size commercial turbofan engine with a representative controller. It is a detailed component level model (CLM) written in the industry-standard graphical MATLAB/Simulink environment to allow for easy modification and portability. At the time of this reporting, no other such model exists in the public domain.

  18. Aero-sol-gel Reactor for Nano-powder Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Beaucage, G.; Hyeon-Lee, J.; Kohls, D.J. [University of Cincinnati, Department of Materials Science and Engineering (United States); Pratsinis, S.E. [University of Cincinnati, Department of Chemical Engineering (United States)

    1999-09-15

    This paper discusses a new approach to the synthesis of nano-structured oxides where sol-gel reactions are carried out in aerosol droplets. This aero-sol-gel (ASG) reactor allows for manipulation of the structure, chemical composition and surface area of silica powders through variation of process parameters. ASG powders differ in nanostructure from other continuous process powders such as pyrolytic and solution-route powders. ASG powders contain mesopores (>2-nm) and micropores (<2-nm), the mesopores being responsible for high surface areas measured by nitrogen adsorption using BET theory. Primary particles of close to molecular scale are believed to lead to exceedingly large specific surface areas on the order of 600-m{sup 2}/g. These primary particles aggregate into nanometer scale mass-fractal aggregates that cluster in micron scale agglomerates. Under controlled reaction conditions the powder structure is reproducible as measured by small-angle X-ray scattering, SAXS, analysis. The ASG reactor displays transport effects similar to those previously seen in laminar flame reactors as evidenced by the effect of reactor geometry and reactant concentration on product structure.

  19. Spatial-temporal-covariance-based modeling, analysis, and simulation of aero-optics wavefront aberrations.

    Science.gov (United States)

    Vogel, Curtis R; Tyler, Glenn A; Wittich, Donald J

    2014-07-01

    We introduce a framework for modeling, analysis, and simulation of aero-optics wavefront aberrations that is based on spatial-temporal covariance matrices extracted from wavefront sensor measurements. Within this framework, we present a quasi-homogeneous structure function to analyze nonhomogeneous, mildly anisotropic spatial random processes, and we use this structure function to show that phase aberrations arising in aero-optics are, for an important range of operating parameters, locally Kolmogorov. This strongly suggests that the d5/3 power law for adaptive optics (AO) deformable mirror fitting error, where d denotes actuator separation, holds for certain important aero-optics scenarios. This framework also allows us to compute bounds on AO servo lag error and predictive control error. In addition, it provides us with the means to accurately simulate AO systems for the mitigation of aero-effects, and it may provide insight into underlying physical processes associated with turbulent flow. The techniques introduced here are demonstrated using data obtained from the Airborne Aero-Optics Laboratory.

  20. Fault Diagnosis of Demountable Disk-Drum Aero-Engine Rotor Using Customized Multiwavelet Method

    Directory of Open Access Journals (Sweden)

    Jinglong Chen

    2015-10-01

    Full Text Available The demountable disk-drum aero-engine rotor is an important piece of equipment that greatly impacts the safe operation of aircraft. However, assembly looseness or crack fault has led to several unscheduled breakdowns and serious accidents. Thus, condition monitoring and fault diagnosis technique are required for identifying abnormal conditions. Customized ensemble multiwavelet method for aero-engine rotor condition identification, using measured vibration data, is developed in this paper. First, customized multiwavelet basis function with strong adaptivity is constructed via symmetric multiwavelet lifting scheme. Then vibration signal is processed by customized ensemble multiwavelet transform. Next, normalized information entropy of multiwavelet decomposition coefficients is computed to directly reflect and evaluate the condition. The proposed approach is first applied to fault detection of an experimental aero-engine rotor. Finally, the proposed approach is used in an engineering application, where it successfully identified the crack fault of a demountable disk-drum aero-engine rotor. The results show that the proposed method possesses excellent performance in fault detection of aero-engine rotor. Moreover, the robustness of the multiwavelet method against noise is also tested and verified by simulation and field experiments.

  1. 75 FR 904 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-01-07

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... Directive (AD) 2009-21-08, which applies to PIAGGIO AERO INDUSTRIES S.p.A. (Piaggio) Model PIAGGIO P-180...: Service information title Page(s) Revision Date PIAGGIO AERO INDUSTRIES S.p.A. 1 through 9........ Rev....

  2. High-Temperature Adhesives for Thermally Stable Aero-Assist Technologies

    Science.gov (United States)

    Eberts, Kenneth; Ou, Runqing

    2013-01-01

    Aero-assist technologies are used to control the velocity of exploration vehicles (EVs) when entering Earth or other planetary atmospheres. Since entry of EVs in planetary atmospheres results in significant heating, thermally stable aero-assist technologies are required to avoid the high heating rates while maintaining low mass. Polymer adhesives are used in aero-assist structures because of the need for high flexibility and good bonding between layers of polymer films or fabrics. However, current polymer adhesives cannot withstand temperatures above 400 C. This innovation utilizes nanotechnology capabilities to address this need, leading to the development of high-temperature adhesives that exhibit high thermal conductivity in addition to increased thermal decomposition temperature. Enhanced thermal conductivity will help to dissipate heat quickly and effectively to avoid temperature rising to harmful levels. This, together with increased thermal decomposition temperature, will enable the adhesives to sustain transient high-temperature conditions.

  3. SFC Optimization for Aero Engine Based on Hybrid GA-SQP Method

    Science.gov (United States)

    Li, Jie; Fan, Ding; Sreeram, Victor

    2013-12-01

    This study focuses on on-line specific fuel consumption (SFC) optimization of aero engines. For solving this optimization problem, a nonlinear pneumatic and thermodynamics model of the aero engine is built and a hybrid optimization technique which is formed by combining the genetic algorithm (GA) and the sequential quadratic programming (SQP) is presented. The ability of standard GA and standard SQP in solving this type of problem is investigated. It has been found that, although the SQP is fast, very little SFC reductions can be obtained. The GA is able to solve the problem well but a lot of computational time is needed. The presented hybrid GA-SQP gives a good SFC optimization effect and saves 76.6% computational time when compared to the standard GA. It has been shown that the hybrid GA-SQP is a more effective and higher real-time method for SFC on-line optimization of the aero engine.

  4. Aero-thermal analysis of lifting body configurations in hypersonic flow

    Science.gov (United States)

    Kumar, Sachin; Mahulikar, Shripad P.

    2016-09-01

    The aero-thermal analysis of a hypersonic vehicle is of fundamental interest for designing its thermal protection system. The aero-thermal environment predictions over several critical regions of the hypothesized lifting body vehicle, including the stagnation region of the nose-cap, cylindrically swept leading edges, fuselage-upper, and fuselage-lower surfaces, are discussed. The drag (Λ=70°) and temperature (Λ=80°) minimized sweepback angles are considered in the configuration design of the two hypothesized lifting body shape hypersonic vehicles. The main aim of the present study is to analyze and compare the aero-thermal characteristics of these two lifting body configurations at same heat capacity. Accordingly, a Computational Fluid Dynamics simulation has been carried out at Mach number (M∞=7), H=35 km altitude with zero Angle of Attack. Finally, the material selection for thermal protection system based on these predictions and current methodology is described.

  5. Frequency-domain Model Matching PID Controller Design for Aero-engine

    Science.gov (United States)

    Liu, Nan; Huang, Jinquan; Lu, Feng

    2014-12-01

    The nonlinear model of aero-engine was linearized at multiple operation points by using frequency response method. The validation results indicate high accuracy of static and dynamic characteristics of the linear models. The improved PID tuning method of frequency-domain model matching was proposed with the system stability condition considered. The proposed method was applied to the design of PID controller of the high pressure rotor speed control in the flight envelope, and the control effects were evaluated by the nonlinear model. Simulation results show that the system had quick dynamic response with zero overshoot and zero steadystate error. Furthermore, a PID-fuzzy switching control scheme for aero-engine was designed, and the fuzzy switching system stability was proved. Simulations were studied to validate the applicability of the multiple PIDs fuzzy switching controller for aero-engine with wide range dynamics.

  6. On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

    Science.gov (United States)

    Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

    2015-01-01

    As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

  7. Aero-MINE (Motionless INtegrated Energy) for Distributed Scalable Wind Power.

    Energy Technology Data Exchange (ETDEWEB)

    Houchens, Brent C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Blaylock, Myra L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-06-01

    The proposed Aero-MINE technology will extract energy from wind without any exterior moving parts. Aero-MINEs can be integrated into buildings or function stand-alone, and are scalable. This gives them advantages similar to solar panels, but with the added benefit of operation in cloudy or dark conditions. Furthermore, compared to solar panels, Aero-MINEs can be manufactured at lower cost and with less environmental impact. Power generation is isolated internally by the pneumatic transmission of air and the outlet air-jet nozzles amplify the effectiveness. Multiple units can be connected to one centrally located electric generator. Aero-MINEs are ideal for the built-environment, with numerous possible configurations ranging from architectural integration to modular bolt-on products. Traditional wind turbines suffer from many fundamental challenges. The fast-moving blades produce significant aero-acoustic noise, visual disturbances, light-induced flickering and impose wildlife mortality risks. The conversion of massive mechanical torque to electricity is a challenge for gears, generators and power conversion electronics. In addition, the installation, operation and maintenance of wind turbines is required at significant height. Furthermore, wind farms are often in remote locations far from dense regions of electricity customers. These technical and logistical challenges add significantly to the cost of the electricity produced by utility-scale wind farms. In contrast, distributed wind energy eliminates many of the logistical challenges. However, solutions such as micro-turbines produce relatively small amounts of energy due to the reduction in swept area and still suffer from the motion-related disadvantages of utility-scale turbines. Aero-MINEs combine the best features of distributed generation, while eliminating the disadvantages.

  8. Finite element analysis of welding residual stress of aero engine blisk by controlling heat input

    Institute of Scientific and Technical Information of China (English)

    Zhang Xueqiu; Yang Jianguo; Chen Xuhui; Fang Hongyuan; Qu Shen; Wang Licheng

    2009-01-01

    In order to improve aero engine performance, it is necessary to reduce the welding residual stress of aero engine blisk. In this paper, finite element method was employed to simulate electron beam welding process of blisk, in accordance with the deducing formula (p = kh) , the heat input is changed with the weld depth to control welding residual stress of blisk. The calculation results show that welding residual stress of blisk can be controlled effectively by reducing the heat input on the conditions of meeting the demand of weld penetration and guaranteeing the welding quality, a new theoretical method and some numerical data are provided for controlling welding residual stress of blisk.

  9. System Aero-Accelator for the purification of biodegradable effluents; Sistema aero-accelator para la depuracion de efluentes biodegradables (I)

    Energy Technology Data Exchange (ETDEWEB)

    Bosque Hernandez, J. L. del; Martin Sanchez, J. L. [Universidad de Salamanca (Spain)

    2000-07-01

    The contamination of the waters is one of the factors that contributes to the deterioration of our environment and since it is a very limited one its treatment descontaminant it is one of the politic's main objectives and environmental administration at all the levels, being spread to the total purification of the generated residual effluents. To reach this objective, big technological efforts are required that allow next to the creation of new processes, the adaptation of the processes existent depuratives, increasing the effectiveness of the same ones. One of the techniques of purification of possible recovery is the Compact System of active mires Aero-Accelator. Presently work is designed and it builds a plant pilot with Aero-Accelator geometry to study its behavior in the treatment of effluents of urban type with different loads pollutants. (Author) 16 refs.

  10. General catalogue of products and services - geology. AERO data base; 2. ed; Catalogo geral de produtos e servicos - geologia. Base de dados AERO

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The catalogue in the second edition aims at presenting to the user a general idea on the aerogeophysical projects of Brazil database (AERO) which belongs to SIGA (Brazilian geological information system). The 151 documents (projects) are listed as follows: 52 projects performed by CPRM/DNPM - Departamento Nacional de Producao Mineral; 33 projects performed by CNEN - Commissao Nacional de Energia Nuclear and NUCLEBRAS; 7 projects executed by State government and private companies; and 59 projects executed for PETROBRAS 159 figs., 5 tabs.

  11. Global dust model intercomparison in AeroCom phase I

    Directory of Open Access Journals (Sweden)

    N. Huneeus

    2011-08-01

    Full Text Available This study presents the results of a broad intercomparison of a total of 15 global aerosol models within the AeroCom project. Each model is compared to observations related to desert dust aerosols, their direct radiative effect, and their impact on the biogeochemical cycle, i.e., aerosol optical depth (AOD and dust deposition. Additional comparisons to Angström exponent (AE, coarse mode AOD and dust surface concentrations are included to extend the assessment of model performance and to identify common biases present in models. These data comprise a benchmark dataset that is proposed for model inspection and future dust model development. There are large differences among the global models that simulate the dust cycle and its impact on climate. In general, models simulate the climatology of vertically integrated parameters (AOD and AE within a factor of two whereas the total deposition and surface concentration are reproduced within a factor of 10. In addition, smaller mean normalized bias and root mean square errors are obtained for the climatology of AOD and AE than for total deposition and surface concentration. Characteristics of the datasets used and their uncertainties may influence these differences. Large uncertainties still exist with respect to the deposition fluxes in the southern oceans. Further measurements and model studies are necessary to assess the general model performance to reproduce dust deposition in ocean regions sensible to iron contributions. Models overestimate the wet deposition in regions dominated by dry deposition. They generally simulate more realistic surface concentration at stations downwind of the main sources than at remote ones. Most models simulate the gradient in AOD and AE between the different dusty regions. However the seasonality and magnitude of both variables is better simulated at African stations than Middle East ones. The models simulate the offshore transport of West Africa throughout the year

  12. Finite element model for aero-elastically tailored residential wind turbine blade design

    Science.gov (United States)

    Robinson, Eric Alan

    Advances in passive wind turbine control systems have allowed wind turbines to achieve higher efficiencies and operate in wider inflow conditions than ever before. Within recent years, the adoption of aero-elastically tailored (bend-twist coupled) composite blades have been a pursued strategy. Unfortunately, for this strategy to be applied, traditional means of modeling, designing and manufacturing are no longer adequate. New parameters regarding non-linearities in deflections, stiffness, and aerodynamic loadings must now be implemented. To aid in the development of passive wind turbine system design, a finite element based aero-elastic program capable of computationally predicting blade deflection and twist under loading was constructed. The program was built around the idea of iteratively solving a blade composite structure to reach a maximum aero-elastic twist configuration under elevated wind speeds. Adopting a pre-existing blade geometry, from a pitch controlled small scale (3.5kW) turbine design, the program was tested to discover the geometry bend-twist coupling potential. This research would be a contributing factor in designing a passive pitch control replacement system for the turbine. A study of various model loading configurations was first performed to insure model validity. Then, a final model was used to analyze composite layups for selected spar configurations. Results characterize the aero-elastic twist properties for the selected configurations.

  13. The effect of harmonized emissions on aerosol properties in global models - an AeroCom experiment

    NARCIS (Netherlands)

    Textor, C.; Schulz, M.; Krol, M.C.

    2007-01-01

    The effects of unified aerosol sources on global aerosol fields simulated by different models are examined in this paper. We compare results from two AeroCom experiments, one with different (ExpA) and one with unified emissions, injection heights, and particle sizes at the source (ExpB). Surprisingl

  14. Dependence of AeroMACS Interference on Airport Radiation Pattern Characteristics

    Science.gov (United States)

    Wilson, Jeffrey D.

    2012-01-01

    AeroMACS (Aeronautical Mobile Airport Communications System), which is based upon the IEEE 802.16e mobile wireless standard, is expected to be implemented in the 5091 to 5150 MHz frequency band. As this band is also occupied by Mobile Satellite Service (MSS) feeder uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference are under analysis in order to enable the definition of standards that assure that such interference will be avoided. In this study, the cumulative interference power distribution at low earth orbit from AeroMACS transmitters at the 497 major airports in the contiguous United States was simulated with the Visualyse Professional software. The dependence of the interference power on the number of antenna beams per airport, gain patterns, and beam direction orientations was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power required to maintain the cumulative interference power under the established threshold.

  15. Computational methods to compute wavefront error due to aero-optic effects

    Science.gov (United States)

    Genberg, Victor; Michels, Gregory; Doyle, Keith; Bury, Mark; Sebastian, Thomas

    2013-09-01

    Aero-optic effects can have deleterious effects on high performance airborne optical sensors that must view through turbulent flow fields created by the aerodynamic effects of windows and domes. Evaluating aero-optic effects early in the program during the design stages allows mitigation strategies and optical system design trades to be performed to optimize system performance. This necessitates a computationally efficient means to evaluate the impact of aero-optic effects such that the resulting dynamic pointing errors and wavefront distortions due to the spatially and temporally varying flow field can be minimized or corrected. To this end, an aero-optic analysis capability was developed within the commercial software SigFit that couples CFD results with optical design tools. SigFit reads the CFD generated density profile using the CGNS file format. OPD maps are then created by converting the three-dimensional density field into an index of refraction field and then integrating along specified paths to compute OPD errors across the optical field. The OPD maps may be evaluated directly against system requirements or imported into commercial optical design software including Zemax® and Code V® for a more detailed assessment of the impact on optical performance from which design trades may be performed.

  16. Application of Multihop Relay for Performance Enhancement of AeroMACS Networks

    Science.gov (United States)

    Kamali, Behnam; Wilson, Jeffrey D.; Kerczewski, Robert J.

    2012-01-01

    A new transmission technology, based on IEEE 802.16-2009 (WiMAX), is currently being developed for airport surface communications. A C-band spectrum allocation at 5091 to 5150 MHz has been created by International Telecommunications Union (ITU) to carry this application. The proposed technology, known as AeroMACS, will be used to support fixed and mobile ground to ground applications and services. This article proposes and demonstrates that IEEE 802.16j-amendment-based WiMAX is most feasible for AeroMACS applications. This amendment introduces multihop relay as an optional deployment that may be used to provide additional coverage and/or enhance the capacity of the network. Particular airport surface radio coverage situations for which IEEE 802.16-2009-WiMAX provides resolutions that are inefficient, costly, or excessively power consuming are discussed. In all these cases, it is argued that 16j technology offers a much better alternative. A major concern about deployment of AeroMACS is interference to co-allocated applications such as the Mobile Satellite Service (MSS) feeder link. Our initial simulation results suggest that no additional interference to MSS feeder link is caused by deployment of IEEE 802.16j-based AeroMACS.

  17. RESEARCH AND DEVELOPMENT OF HIGH TEMPERATURE STRUCTURAL MATERIALS FOR AERO-ENGINE APPLICATIONS

    Institute of Scientific and Technical Information of China (English)

    G.Q. Zhang

    2005-01-01

    The status of research, development of superalloys and materials processing & fabrication technologies for aero-engine applications in China Aviation Industry, with an emphasis on recent achievements at BIAM including directionally solidified and single crystal superalloys for blade and vane applications, wrought superalloys for aero-engine disks and rings, and powder metallurgy (PM) superalloys for high performance disk applications were described. It was also reviewed the development of new class of high temperature structural materials, such as structural intermetallics, and advanced material processing technologies including rapid solidification,spray forming and so on. The trends of research and development of the above mentioned superalloys and processing technologies are outlined. Cast, wrought and PM superalloys are the workhorse materials for the hot section of current aero-engines. New high temperature materials and advanced processing technologies have been and will be the subject of study. It is speculated that high performance, high purity and low cost superalloys and technologies will play key roles in aero-engines.

  18. Analysis and quantification of the diversities of aerosol life cycles within AeroCom

    NARCIS (Netherlands)

    Textor, C.; Schulz, M.; Guibert, S.; Kinne, S.; Balkanski, Y.; Bauer, S.; Berntsen, T.; Berglen, T.; Boucher, O.; Chin, M.; Dentener, F.; Diehl, T.; Easter, R.; Feichter, H.; Fillmore, D.; Ghan, S.; Ginoux, P.; Gong, S.; Grini, A.; Hendricks, J.; Horowitz, L.; Huang, P.; Isaksen, I.; Iversen, T.; Kloster, S.; Koch, D.; Kirkevåg, A.; Kristjansson, J.E.; Krol, M.C.; Lauer, A.; Lamarque, J.F.; Liu, X.; Montanaro, V.; Myhre, G.; Penner, J.; Pitari, G.; Reddy, S.; Seland, O.; Stier, P.; Takemura, T.; Tie, X.

    2006-01-01

    Simulation results of global aerosol models have been assembled in the framework of the AeroCom intercomparison exercise. In this paper, we analyze the life cycles of dust, sea salt, sulfate, black carbon and particulate organic matter as simulated by sixteen global aerosol models. The differences a

  19. Simultaneous measurement of aero-optical distortion and turbulent structure in a heated boundary layer

    Science.gov (United States)

    Saxton-Fox, Theresa; McKeon, Beverley; Smith, Adam; Gordeyev, Stanislav

    2014-11-01

    This study examines the relationship between turbulent structures and the aero-optical distortion of a laser beam passing through a turbulent boundary layer. Previous studies by Smith et al. (AIAA, 2014--2491) have found a bulk convection velocity of 0 . 8U∞ for aero-optical distortion in turbulent boundary layers, motivating a comparison of the distortion with the outer boundary layer. In this study, a turbulent boundary layer is developed over a flat plate with a moderately-heated section of length 25 δ . Density variation in the thermal boundary layer leads to aero-optical distortion, which is measured with a Malley probe (Smith et al., AIAA, 2013--3133). Simultaneously, 2D PIV measurements are recorded in a wall-normal, streamwise plane centered on the Malley probe location. Experiments are run at Reθ = 2100 and at a Mach number of 0.03, with the heated wall 10 to 20°C above the free stream temperature. Correlations and conditional averages are carried out between Malley probe distortion angles and flow features in the PIV vector fields. Aero-optical distortion in this study will be compared to distortion in higher Mach number flows studied by Gordeyev et al. (J. Fluid Mech., 2014), with the aim of extending conclusions into compressible flows. This research is made possible by the Department of Defense through the National Defense & Engineering Graduate Fellowship (NDSEG) Program and by the Air Force Office of Scientific Research Grant # FA9550-12-1-0060.

  20. Large Wind Turbine Rotor Design using an Aero-Elastic / Free-Wake Panel Coupling Code

    DEFF Research Database (Denmark)

    Sessarego, Matias; Ramos García, Néstor; Shen, Wen Zhong;

    2016-01-01

    Despite the advances in computing resources in the recent years, the majority of large wind-turbine rotor design problems still rely on aero-elastic codes that use blade element momentum (BEM) approaches to model the rotor aerodynamics. The present work describes an approach to wind-turbine rotor...

  1. 76 FR 27872 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model P-180 Airplanes

    Science.gov (United States)

    2011-05-13

    ... INDUSTRIES S.p.A Model P- 180 Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ] ACTION: Final... known U.S. owners and operators of PIAGGIO AERO INDUSTRIES S.p.A (Piaggio) Model PIAGGIO P-180 airplanes... fuselage on a number of Piaggio Model P.180 aeroplanes, which resulted in jamming of the flight...

  2. 77 FR 63712 - Airworthiness Directives; Piaggio Aero Industries S.p.A.

    Science.gov (United States)

    2012-10-17

    ... Industries S.p.A. AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION... Aero Industries S.p.A Model P-180 airplanes. That AD was prompted by mandatory continuing airworthiness... replaced for damage in the P.180 fleet since that occurrence. Based on the available information, this...

  3. 75 FR 5690 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A. Model P-180 Airplanes

    Science.gov (United States)

    2010-02-04

    ... INDUSTRIES S.p.A. Model P- 180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM...: 2010-03-04 PIAGGIO AERO INDUSTRIES S.p.A.: Amendment 39-16187; Docket No. FAA-2009-1081;...

  4. Recognition and practice on remanufacturing engineering management of military aero-engines

    Institute of Scientific and Technical Information of China (English)

    Xiang Qiao

    2014-01-01

    The technologies of design,manufacture and MRO (maintenance,repair and overhaul) for the mili-tary aero-engines,particularly for the fighters,are much more difficult to be mastered than those for any other aero-engines. They have been monopolized by only a few countries and the core technologies have never been transferred due to high risk,high investment,high barrier and high cost. Therefore,our country has long relied on mapping and copying the others’engines to satisfy the domestic demand due to not having our own indepen-dent technologies for the design and manufacture of military aero-engines. However,through over 20 years of unremitting effort,the independent MRO has been achieved for all the Chinese fighter engines,covering in-R&D (research and development) and in-service engines;and the MRO technologies,capabilities,quality, cost-efficiency have reached or exceeded those of original manufacturers. It has grown out of nothing,and then from weak to strong. In particular,dozens of projects concerning the R&D and engineering application of re-manufacturing have obtained the independent intellectual property rights and are playing an irreplaceable role in achieving leaping improvement of independent MRO for Chinese military aero-engines.

  5. Recognition and practice on remanufacturing engineering management of military aero-engines

    Institute of Scientific and Technical Information of China (English)

    Xiang Qiao

    2014-01-01

    The technologies of design, manufacture and MRO (maintenance, repair and overhaul) tor the mili- tary aero-engines, particularly for the fighters, are much more difficult to be mastered than those for any other aero-engines. They have been monopolized by only a few countries and the core technologies have never been transferred due to high risk, high investment, high barrier and high cost. Therefore, our country has long relied on mapping and copying the others' engines to satisfy the domestic demand due to not having our own indepen- dent technologies for the design and manufacture of military aero-engines. However, through over 20 years of unremitting effort, the independent MRO has been achieved for all the Chinese fighter engines, covering in- R&D (research and development) and in-service engines; and the MRO technologies, capabilities, quality, cost-efficiency have reached or exceeded those of original manufacturers. It has grown out of nothing, and then from weak to strong. In particular, dozens of projects concerning the R&D and engineering application of re- manufacturing have obtained the independent intellectual property rights and are playing an irreplaceable role in achieving leaping improvement of independent MRO for Chinese military aero-engines.

  6. Global dust model intercomparison in AeroCom phase I

    Directory of Open Access Journals (Sweden)

    N. Huneeus

    2010-10-01

    Full Text Available Desert dust plays an important role in the climate system through its impact on Earth's radiative budget and its role in the biogeochemical cycle as a source of iron in high-nutrient-low-chlorophyll regions. A large degree of diversity exists between the many global models that simulate the dust cycle to estimate its impact on climate. We present the results of a broad intercomparison of a total of 15 global aerosol models within the AeroCom project. Each model is compared to observations focusing on variables responsible for the uncertainties in estimating the direct radiative effect and the dust impact on the biogeochemical cycle, i.e., aerosol optical depth (AOD and dust deposition. Additional comparisons to Angström Exponent (AE, coarse mode AOD and dust surface concentration are included to extend the assessment of model performance. These datasets form a benchmark data set which is proposed for model inspection and future dust model developments. In general, models perform better in simulating climatology of vertically averaged integrated parameters (AOD and AE in dusty sites than they do with total deposition and surface concentration. Almost all models overestimate deposition fluxes over Europe, the Indian Ocean, the Atlantic Ocean and ice core data. Differences among the models arise when simulating deposition at remote sites with low fluxes over the Pacific and the Southern Atlantic Ocean. This study also highlights important differences in models ability to reproduce the deposition flux over Antarctica. The cause of this discrepancy could not be identified but different dust regimes at each site and issues with data quality should be considered. Models generally simulate better surface concentration at stations downwind of the main sources than at remote ones. Likewise, they simulate better surface concentration at stations affected by Saharan dust than at stations affected by Asian dust. Most models simulate the gradient in AOD and

  7. Understanding Aero-Fractures using optics and acoustics

    Science.gov (United States)

    Turkaya, Semih; Toussaint, Renaud; Kvalheim Eriksen, Fredrik; Zecevic, Megan; Daniel, Guillaume; Grude Flekkøy, Eirik; Jørgen Måløy, Knut

    2016-04-01

    exponent p value around 0.5. An analytical model of overpressure diffusion predicting p = 0.5 and two other free parameters of the Omori Law (prefactor and origin time) is developed. The spatial density of the seismic events, and the time of end of formation of the channels can also be predicted using this developed model. Using direct simulations of acoustic emissions due to the air vibration in opening fractal cavities, the evolution in the power spectrum is investigated. 1. Turkaya S, Toussaint R, Eriksen FK, Zecevic M, Daniel G, Flekkøy EG, Måløy KJ. "Bridging aero-fracture evolution with the characteristics of the acoustic emissions in a porous medium." Front. Phys.3:70. 2015 doi: 10.3389/fphy.2015.00070

  8. Fusing Simulation Results From Multifidelity Aero-servo-elastic Simulators - Application To Extreme Loads On Wind Turbine

    DEFF Research Database (Denmark)

    Abdallah, Imad; Sudret, Bruno; Lataniotis, Christos

    2015-01-01

    Fusing predictions from multiple simulators in the early stages of the conceptual design of a wind turbine results in reduction in model uncertainty and risk mitigation. Aero-servo-elastic is a term that refers to the coupling of wind inflow, aerodynamics, structural dynamics and controls. Fusing...... the response data from multiple aero-servo-elastic simulators could provide better predictive ability than using any single simulator. The co-Kriging approach to fuse information from multifidelity aero-servo-elastic simulators is presented. We illustrate the co-Kriging approach to fuse the extreme flapwise...... bending moment at the blade root of a large wind turbine as a function of wind speed, turbulence and shear exponent in the presence of model uncertainty and non-stationary noise in the output. The extreme responses are obtained by two widely accepted numerical aero-servo-elastic simulators, FAST...

  9. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    National Research Council Canada - National Science Library

    B. Sasi; B.P.C. Rao; T. Jayakumar

    2004-01-01

    ... related aircraft components. This paper discusses a dual-frequency eddy current testing procedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability...

  10. Smart Rotor Modeling: Aero-Servo-Elastic Modeling of a Smart Rotor with Adaptive Trailing Edge Flaps

    DEFF Research Database (Denmark)

    Bergami, Leonardo

    This book presents the formulation of an aero-servo-elastic model for a wind turbine rotor equipped with Adaptive Trailing Edge Flaps (ATEF), a smart rotor configuration. As the name suggests, an aero-servo-elastic model consists of three main components: an aerodynamic model, a structural model......, and a control model. The book first presents an engineering type of aerodynamic model that accounts for the dynamic effects of flap deflection. The aerodynamic model is implemented in a Blade Element Momentum framework, and coupled with a multi-body structural model in the aero-servoelastic simulation code HAWC...... the trailing edge flap deflection to actively reduce the fatigue loads on the structure. The performance of the smart rotor configuration and its control algorithms are finally quantified by aero-servo-elastic simulations of the smart rotor turbine operating in a standard turbulent wind field....

  11. Computational Aero-acoustics As a Tool For Turbo-machinery Noise Reduction

    Science.gov (United States)

    Dyson, Rodger W.

    2003-01-01

    This talk will provide an overview of the field of computational aero-acoustics and its use in fan noise prediction. After a brief history of computational fluid dynamics, some of the recent developments in computational aero-acoustics will be explored. Computational issues concerning sound wave production, propagation, and reflection in practical turbo-machinery applications will be discussed including: (a) High order/High Resolution Numerical Techniques. (b) High Resolution Boundary Conditions. [c] MIMD Parallel Computing. [d] Form of Governing Equations Useful for Simulations. In addition, the basic design of our Broadband Analysis Stator Simulator (BASS) code and its application to a 2 D rotor wake-stator interaction will be shown. An example of the noise produced by the wakes from a rotor impinging upon a stator cascade will be shown.

  12. Aero-allergens in canine atopic dermatitis in southeastern Australia based on 1000 intradermal skin tests.

    Science.gov (United States)

    Mueller, R S; Bettenay, S V; Tideman, L

    2000-06-01

    To determine the most relevant aero-allergens involved in canine atopic dermatitis in southeastern Australia and provide information about these aero-allergens to the general practitioner. Dogs presented to the Animal Skin & Allergy Clinic with history and clinical signs of atopic dermatitis were injected intradermally with 38 different allergens and negative and positive control. Intradermal skin tests in 1000 dogs were retrospectively evaluated. One third of all patients reacted to the house dust mite Dermatophagoides farinae. Allergens reacting in more than 15% of the patients were wheat (Triticum aestivum), sweet vernal (Anthoxanthum odoratum), English couch (Agropyron repens), yellow dock (Rumex crispus), Mexican tea (Chenopodium ambrosioides), plantain (Plantago lanceolata), melaleuca (Melaleuca quinquenervia) and peppercorn (Schimus spp). House dust mites are the most common allergens in canine atopic dermatitis in southeastern Australia and D farinae is involved most frequently. However, a number of grass, weed and tree pollens also are involved regularly.

  13. Studies on dynamic characteristics of the joint in the aero-engine rotor system

    Science.gov (United States)

    Shuguo, Liu; Yanhong, Ma; Dayi, Zhang; Jie, Hong

    2012-05-01

    The joint as a major part of the aero-engine rotating shafts directly influences its rotordynamics and state stability. This paper studies the dynamic effects of structure parameters and the external load on the stiffness and contact state of the rotor joints with nonlinear finite-element method and experiments. And a sensitivity analysis of critical speeds and vibration modes with respect to typical parameters (stiffness of the spline joints) is performed with finite difference methods, through two approaches, i.e. relative sensitivity analysis and absolute sensitivity analysis. The study results show that the stiffness and contact state of joints vary with external loads and geometry structures, and affect the rotor system operating. It is advisable to consider the influence of the position, structural parameter and external load of the rotor joints on aero-engine structure dynamics design.

  14. Large Wind Turbine Rotor Design using an Aero-Elastic / Free-Wake Panel Coupling Code

    Science.gov (United States)

    Sessarego, Matias; Ramos-García, Néstor; Shen, Wen Zhong; Nørkær Sørensen, Jens

    2016-09-01

    Despite the advances in computing resources in the recent years, the majority of large wind-turbine rotor design problems still rely on aero-elastic codes that use blade element momentum (BEM) approaches to model the rotor aerodynamics. The present work describes an approach to wind-turbine rotor design by incorporating a higher-fidelity free-wake panel aero-elastic coupling code called MIRAS-FLEX. The optimization procedure includes a series of design load cases and a simple structural design code. Due to the heavy MIRAS-FLEX computations, a surrogate-modeling approach is applied to mitigate the overall computational cost of the optimization. Improvements in cost of energy, annual energy production, maximum flap-wise root bending moment, and blade mass were obtained for the NREL 5MW baseline wind turbine.

  15. [Aerobic and aero-anaerobic bacterial flora of the nasal cavities of lambs].

    Science.gov (United States)

    Menoueri, N; Richard, Y; Brunet, J; Oudar, J

    1988-01-01

    On the basis of bacteriological examinations carried out on 415 intranasal swabs, aerobic and aero-anaerobic respiratory microbes were studied in lambs. A great diversity of bacteria has been found (in total 35 bacterial species and genus have been identified). This flora is characterised by the presence of gram positive cocci with a gram negative strain included in genus Moraxella and connected with Moraxella bovis species.

  16. Aero-elastic stability of airfoil flow using 2-D CFD

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, J. [Risoe National Lab., Roskilde (Denmark)

    1999-03-01

    A three degrees-of-freedom structural dynamics model has been coupled to a two-dimensional incompressible CFD code. The numerical investigation considers aero-elastic stability for two different airfoils; the NACA0012 and the LM 2 18 % airfoils. Stable and unstable configurations and limit cycle oscillations are predicted in accordance with literature for the first airfoil. An attempt to predict stall induced edge-wise vibrations on a wind turbine airfoil fails using this two-dimensional approach. (au)

  17. Integrated Line-of-Sight Modeling of the Airborne Aero-Optics Laboratory

    Science.gov (United States)

    2013-09-01

    compensator. The PID coefficients were adjusted to match the measured behavior. The measured and tuned results are shown in Fig. 6. Measured Tuned ...strain energy in the bond between them. As with the measured data, this mode is destabilized in the tuned model as shown in Figure 6 with the PID ...uncertainty with model tuning based on available experimental measurements was examined for one flight condition. 2. INTRODUCTION The Airborne Aero

  18. Aero-/hydro-elastic stability of flexible panels: Prediction and control using localised spring support

    Science.gov (United States)

    Tan, B. H.; Lucey, A. D.; Howell, R. M.

    2013-12-01

    We study the effect of adding localised stiffness, via a spring support, on the stability of flexible panels subjected to axial uniform incompressible flow. Applications are considered that range from the hydro-elasticity of hull panels of high-speed ships to the aero-elasticity of glass panels in the curtain walls of high-rise buildings in very strong winds. A two-dimensional linear analysis is conducted using a hybrid of theoretical and computational methods that calculates the system eigen-states but can also be used to capture the transient behaviour that precedes these. We show that localised stiffening is a very effective means to increase the divergence-onset flow speed in both hydro- and aero-elastic applications. It is most effective when located at the mid-chord of the panel and there exists an optimum value of added stiffness beyond which further increases to the divergence-onset flow speed do not occur. For aero-elastic applications, localised stiffening can be used to replace the more destructive flutter instability that follows divergence at higher flow speeds by an extended range of divergence. The difference in eigen-solution morphology between aero- and hydro-elastic applications is highlighted, showing that for the former coalescence of two non-oscillatory divergence modes is the mechanism for flutter onset. This variation in solution morphology is mapped out in terms of a non-dimensional mass ratio. Finally, we present a short discussion of the applicability of the stabilisation strategy in a full three-dimensional system.

  19. A comparison between different finite elements for elastic and aero-elastic analyses.

    Science.gov (United States)

    Mahran, Mohamed; ELsabbagh, Adel; Negm, Hani

    2017-11-01

    In the present paper, a comparison between five different shell finite elements, including the Linear Triangular Element, Linear Quadrilateral Element, Linear Quadrilateral Element based on deformation modes, 8-node Quadrilateral Element, and 9-Node Quadrilateral Element was presented. The shape functions and the element equations related to each element were presented through a detailed mathematical formulation. Additionally, the Jacobian matrix for the second order derivatives was simplified and used to derive each element's strain-displacement matrix in bending. The elements were compared using carefully selected elastic and aero-elastic bench mark problems, regarding the number of elements needed to reach convergence, the resulting accuracy, and the needed computation time. The best suitable element for elastic free vibration analysis was found to be the Linear Quadrilateral Element with deformation-based shape functions, whereas the most suitable element for stress analysis was the 8-Node Quadrilateral Element, and the most suitable element for aero-elastic analysis was the 9-Node Quadrilateral Element. Although the linear triangular element was the last choice for modal and stress analyses, it establishes more accurate results in aero-elastic analyses, however, with much longer computation time. Additionally, the nine-node quadrilateral element was found to be the best choice for laminated composite plates analysis.

  20. Mode shape description of an aero-engine casing structure using Zernike moment descriptors

    Institute of Scientific and Technical Information of China (English)

    LIU Ying-chao; ZANG Chao-ping

    2011-01-01

    Vibration mode shape description of an aero-engine casing structure using Zernike moment descriptor (ZMD) was introduced in this paper. The mode shapes of the aero-engine casing structure can be decomposed as a linear combination of a series of Zernike polynomials, with the feature of each Zernike polynomial reflecting a part of characteristic of mode shapes, based on Zernike moment transformation. Meanwhile, the reconstruction of mode shapes with ZMD was explored and its ability to filtering the noise contaminated in the mode shapes was studied. Simulation of the aero-engine casing structure indicated the advantage of this method to depict the mode shapes of a symmetric structure. Results demonstrate that the Zernike moment description of the mode shapes can effectively describe the double modes in the symmetric structure and also has the ability to remove or significantly reduce the influence of noise in the mode shapes. Such feature shows great practical value for further research on the correlation, model updating and model validation of the symmetric structure's finite element model.

  1. RANDOM-FUZZY SAFETY ANALYSIS FOR AN AERO ENGINE TURBINE DISK

    Institute of Scientific and Technical Information of China (English)

    Z.Z. Lü; C.L. Liu; Y.L. Xu; Z.F. Yue

    2004-01-01

    A numerical simulation method is presented for the random-fuzzy safety analysis of an aero engine disk. Based on the equivalent transformation from a fuzzy variable to a random variable, the equivalent random Probability Density Functions(PDFs)are got from their corresponding Fuzzy Possibility Distributions(FPDs) for the fuzzy variables. In that case the perfect numerical simulation method for the random uncertainty is employed to solve the fuzzy uncertainty. For the complex structure such as the aero engine disk with implicit relationship between the input basic variable and the response variable, the equivalent PDFs of the input basic variables are delivered simultaneously to the response variable by an empirical PDF, which is simulated by Finite Element Method(FEM). Then, in view of the fuzzy application requirement occurring in engineering usually, the reliability definition and calculation are discussed for the aero engine disk with multiple fuzzy failure modes. On the other hand, through the inverse transformation of the fuzzy variable to the random variable, the FPDs of the response variables can be calculated from their empirical PDFs as well.

  2. AeroCom INSITU Project: Comparing modeled and measured aerosol optical properties

    Science.gov (United States)

    Andrews, Elisabeth; Schmeisser, Lauren; Schulz, Michael; Fiebig, Markus; Ogren, John; Bian, Huisheng; Chin, Mian; Easter, Richard; Ghan, Steve; Kokkola, Harri; Laakso, Anton; Myhre, Gunnar; Randles, Cynthia; da Silva, Arlindo; Stier, Phillip; Skeie, Ragnehild; Takemura, Toshihiko; van Noije, Twan; Zhang, Kai

    2016-04-01

    AeroCom, an open international collaboration of scientists seeking to improve global aerosol models, recently initiated a project comparing model output to in-situ, surface-based measurements of aerosol optical properties. The model/measurement comparison project, called INSITU, aims to evaluate the performance of a suite of AeroCom aerosol models with site-specific observational data in order to inform iterative improvements to model aerosol modules. Surface in-situ data has the unique property of being traceable to physical standards, which is an asset in accomplishing the overall goal of bettering the accuracy of aerosols processes and the predicative capability of global climate models. Here we compare dry, in-situ aerosol scattering and absorption data from ~75 surface, in-situ sites from various global aerosol networks (including NOAA, EUSAAR/ACTRIS and GAW) with a simulated optical properties from a suite of models participating in the AeroCom project. We report how well models reproduce aerosol climatologies for a variety of time scales, aerosol characteristics and behaviors (e.g., aerosol persistence and the systematic relationships between aerosol optical properties), and aerosol trends. Though INSITU is a multi-year endeavor, preliminary phases of the analysis suggest substantial model biases in absorption and scattering coefficients compared to surface measurements, though the sign and magnitude of the bias varies with location. Spatial patterns in the biases highlight model weaknesses, e.g., the inability of models to properly simulate aerosol characteristics at sites with complex topography. Additionally, differences in modeled and measured systematic variability of aerosol optical properties suggest that some models are not accurately capturing specific aerosol behaviors, for example, the tendency of in-situ single scattering albedo to decrease with decreasing aerosol extinction coefficient. The endgoal of the INSITU project is to identify specific

  3. Reliability analysis of aero-engine blades considering nonlinear strength degeneration

    Institute of Scientific and Technical Information of China (English)

    Lin Jiewei; Zhang Junhong; Yang Shuo; Bi Fengrong

    2013-01-01

    To comprehensively consider the effects of strength degeneration and failure correlation,an improved stress-strength interference (SSI) model is proposed to analyze the reliability of aeroengine blades with the fatigue failure mode.Two types of TC4 alloy experiments are conducted for the study on the damage accumulation law.All the parameters in the nonlinear damage model are obtained by the tension-compression fatigue tests,and the accuracy of the nonlinear damage model is verified by the damage tests.The strength degeneration model is put forward on the basis of the Chaboche nonlinear damage theory and the Griffith fracture criterion,and determined by measuring the fatigue toughness during the tests.From the comparison of two kinds of degeneration models based on the Miner's linear law and the nonlinear damage model respectively,the nonlinear model has a significant advantage on prediction accuracy especially in the later period of life.A time-dependent SSI reliability model is established.By computing the stress distribution using the finite element (FE) technique,the reliability of a single blade during the whole service life is obtained.Considering the failure correlation of components,a modified reliability model of aero-engine blades with common cause failure (CCF) is presented.It shows a closer and more reasonable process with the actual working condition.The improved reliability model is illustrated to be applied to aero-engine blades well,and the approach purposed in this paper is suitable for any actual machinery component of aero-engine rotor systems.

  4. Dynamical mechanism in aero-engine gas path system using minimum spanning tree and detrended cross-correlation analysis

    Science.gov (United States)

    Dong, Keqiang; Zhang, Hong; Gao, You

    2017-01-01

    Identifying the mutual interaction in aero-engine gas path system is a crucial problem that facilitates the understanding of emerging structures in complex system. By employing the multiscale multifractal detrended cross-correlation analysis method to aero-engine gas path system, the cross-correlation characteristics between gas path system parameters are established. Further, we apply multiscale multifractal detrended cross-correlation distance matrix and minimum spanning tree to investigate the mutual interactions of gas path variables. The results can infer that the low-spool rotor speed (N1) and engine pressure ratio (EPR) are main gas path parameters. The application of proposed method contributes to promote our understanding of the internal mechanisms and structures of aero-engine dynamics.

  5. Development and Validation of a New Blade Element Momentum Skewed-Wake Model within AeroDyn: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ning, S. A.; Hayman, G.; Damiani, R.; Jonkman, J.

    2014-12-01

    Blade element momentum methods, though conceptually simple, are highly useful for analyzing wind turbines aerodynamics and are widely used in many design and analysis applications. A new version of AeroDyn is being developed to take advantage of new robust solution methodologies, conform to a new modularization framework for National Renewable Energy Laboratory's FAST, utilize advanced skewed-wake analysis methods, fix limitations with previous implementations, and to enable modeling of highly flexible and nonstraight blades. This paper reviews blade element momentum theory and several of the options available for analyzing skewed inflow. AeroDyn implementation details are described for the benefit of users and developers. These new options are compared to solutions from the previous version of AeroDyn and to experimental data. Finally, recommendations are given on how one might select from the various available solution approaches.

  6. Qualification of Indigenously Developed Special Coatings for Aero-Engine Components

    Directory of Open Access Journals (Sweden)

    V. Sambasiva Rao

    1999-10-01

    Full Text Available The demand for higher performance and reliability of aero-engiaes necessitates its components to worksatisfactorily under severe operating conditions. The durability of various components in these environmentis often enhanced by applying suitable coatings. The development of new materials/processing methods andalso various coatings to protect the components have been driven by the ever-increasing severity of theaero-engine internal environment. While the selection of a coating is dictated by the operating conditionsand the nature of the environment and also on the substrate, the durability of the coating depends uponthe mode of degradation of the coating and substrate in service.Though certification of an aero-engine after developmt obviously includes: validation of the componentsand its coatings, indigenous substitution of an already-qualified component system requires a re-orientationof the qualification methodology. This paper describes an approach for qualification of indigenously developedspecial coatings processes for application on aero-engine components. This approach has been adoptedsuccesshlly in validating several indigenous coatingslpmcesses, viz, aluminium-silicon diffusion coating appliedby pack cementation for oxidationhot comsion resistance, cobalt-chromium carbide coating by electrodepositionfor wear resistance, chromium carbide-nickel chromium coating applied by detonation gun and yttria-stabilisedzirconia thermal barrier coating applied by plasma spray.The approaih consists of a series of validation tests configured to assess the coating-substrate system.The rationale in evolving the qualification tests based on the type of coating, coating process, operating conditionsfor the components, probable failure modes and coating-base metal interaction, are described. In addition,comparison of the test results obtained on the test specimens coated with indigenously developed coatingsand imported coatings is also enumerated to show

  7. Derivation of Aero-Induced Fluctuating Pressure Environments for Ares I-X

    Science.gov (United States)

    Yang, Michael Y.; Wilby, John F.

    2008-01-01

    A description is given of the external aero-inducted fluctuating pressure model which was fit and anchored to wind tunnel data from the past 40 years. This model is based upon the assumption that the flow around a vehicle can be divided into discrete flow zones with independent fluctuating pressure properties. The model is then used to derive fluctuating pressure environments during ascent for the Ares I-X test vehicle. A sensitivity study of the structural response to the spatial correlation of the fluctuating pressures is also performed.

  8. RELIABILITY ANALYSIS FOR AN AERO ENGINE TURBINE DISK UNDER LOW CYCLE FATIGUE CONDITION

    Institute of Scientific and Technical Information of China (English)

    C.L. Liu; Z.Z. Lü; Y.L. Xu

    2004-01-01

    Reliability analysis methods based on the linear damage accumulation law (LDAL) and load-life interference model are studied in this paper. According to the equal probability rule, the equivalent loads are derived, and the reliability analysis method based on load-life interference model and recurrence formula is constructed. In conjunction with finite element analysis (FEA) program, the reliability of an aero engine turbine disk under low cycle fatigue (LCF) condition has been analyzed. The results show the turbine disk is safety and the above reliability analysis methods are feasible.

  9. Large Wind Turbine Rotor Design using an Aero-Elastic / Free-Wake Panel Coupling Code

    DEFF Research Database (Denmark)

    Sessarego, Matias; Ramos García, Néstor; Shen, Wen Zhong;

    2016-01-01

    Despite the advances in computing resources in the recent years, the majority of large wind-turbine rotor design problems still rely on aero-elastic codes that use blade element momentum (BEM) approaches to model the rotor aerodynamics. The present work describes an approach to wind-turbine rotor...... the overall computational cost of the optimization. Improvements in cost of energy, annual energy production, maximum ap-wise root bending moment, and blade mass were obtained for the NREL 5MW baseline wind turbine....

  10. Recent trends in superalloys research for critical aero-engine components

    Energy Technology Data Exchange (ETDEWEB)

    Remy, Luc [Mine ParisTech, CNRS UMR 7633, 91 - Evry (France). Centre des Materiaux; Guedou, Jean-Yves [Snecma Safran Group, Moissy-Cramayel (France). Materials and Processes Dept.

    2010-07-01

    This paper is a brief survey of common research activity on superalloys for aero-engines between Snecma and Mines ParisTech Centre des Materiaux during recent years. First in disks applications, the development of new powder metallurgy superalloys is shown. Then grain boundary engineering is investigated in a wrought superalloy. Secondly, design oriented research on single crystals blades is shown: a damage model for low cycle fatigue is used for life prediction when cracks initiated at casting pores. The methodology developed for assessing coating life is illustrated for thermal barrier coating deposited on AMI single crystal superalloy. (orig.)

  11. A novel full scale experimental characterization of wind turbine aero-acoustic noise sources - preliminary results

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Bertagnolio, Franck; Fischer, Andreas;

    2016-01-01

    The paper describes a novel full scale experiment on a 500 kW wind turbine with the main objective to characterize the aero-acoustic noise sources. The idea behind the instrumentation is to study the link and correlation between the surface pressure (SP) fluctuations in the boundary layer...... of the blade and the noise on the ground in a distance of about one rotor diameter. In total six surface microphones were used to measure the SP at the leading edge (LE) and trailing edge (TE) of the blade. In parallel noise was measured by eight microphones placed on plates on the ground around the turbine...

  12. Statistical learning methods for aero-optic wavefront prediction and adaptive-optic latency compensation

    Science.gov (United States)

    Burns, W. Robert

    Since the early 1970's research in airborne laser systems has been the subject of continued interest. Airborne laser applications depend on being able to propagate a near diffraction-limited laser beam from an airborne platform. Turbulent air flowing over the aircraft produces density fluctuations through which the beam must propagate. Because the index of refraction of the air is directly related to the density, the turbulent flow imposes aberrations on the beam passing through it. This problem is referred to as Aero-Optics. Aero-Optics is recognized as a major technical issue that needs to be solved before airborne optical systems can become routinely fielded. This dissertation research specifically addresses an approach to mitigating the deleterious effects imposed on an airborne optical system by aero-optics. A promising technology is adaptive optics: a feedback control method that measures optical aberrations and imprints the conjugate aberrations onto an outgoing beam. The challenge is that it is a computationally-difficult problem, since aero-optic disturbances are on the order of kilohertz for practical applications. High control loop frequencies and high disturbance frequencies mean that adaptive-optic systems are sensitive to latency in sensors, mirrors, amplifiers, and computation. These latencies build up to result in a dramatic reduction in the system's effective bandwidth. This work presents two variations of an algorithm that uses model reduction and data-driven predictors to estimate the evolution of measured wavefronts over a short temporal horizon and thus compensate for feedback latency. The efficacy of the two methods are compared in this research, and evaluated against similar algorithms that have been previously developed. The best version achieved over 75% disturbance rejection in simulation in the most optically active flow region in the wake of a turret, considerably outperforming conventional approaches. The algorithm is shown to be

  13. A Virtual Assembly System for Aero-engines Based on VR

    Institute of Scientific and Technical Information of China (English)

    GAO Ying; GUO Yun-peng; SHAO Ya-nan; XU Zhi-guo

    2008-01-01

    In this paper, a synthesized technique is explored through design of a virtual experiment system for main aeroengine based on VR, which attempts to integrate some VR techniques, such as 3D stereo simulation and modeling, 3D scene management and human-computer virtual assembly based on data glove and collision detection. The geometry modeling and instantiation technique, virtual hand modeling and data glove interaction technique are discussed chiefly. Finally, taking aim at assembling and dismantling experiment system of a certain aero-engine, interface technology is expounded also.

  14. Aero-servo-viscoelasticity theory: Lifting surfaces, plates, velocity transients, flutter, and instability

    Science.gov (United States)

    Merrett, Craig G.

    Modern flight vehicles are fabricated from composite materials resulting in flexible structures that behave differently from the more traditional elastic metal structures. Composite materials offer a number of advantages compared to metals, such as improved strength to mass ratio, and intentional material property anisotropy. Flexible aircraft structures date from the Wright brothers' first aircraft with fabric covered wooden frames. The flexibility of the structure was used to warp the lifting surface for flight control, a concept that has reappeared as aircraft morphing. These early structures occasionally exhibited undesirable characteristics during flight such as interactions between the empennage and the aft fuselage, or control problems with the elevators. The research to discover the cause and correction of these undesirable characteristics formed the first foray into the field of aeroelasticity. Aeroelasticity is the intersection and interaction between aerodynamics, elasticity, and inertia or dynamics. Aeroelasticity is well suited for metal aircraft, but requires expansion to improve its applicability to composite vehicles. The first is a change from elasticity to viscoelasticity to more accurately capture the solid mechanics of the composite material. The second change is to include control systems. While the inclusion of control systems in aeroelasticity lead to aero-servo-elasticity, more control possibilities exist for a viscoelastic composite material. As an example, during the lay-up of carbon-epoxy plies, piezoelectric control patches are inserted between different plies to give a variety of control options. The expanded field is called aero-servo-viscoelasticity. The phenomena of interest in aero-servo-viscoelasticity are best classified according to the type of structure considered, either a lifting surface or a panel, and the type of dynamic stability present. For both types of structures, the governing equations are integral

  15. Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations

    Science.gov (United States)

    Myhre, G.; Samset, B. H.; Schulz, M.; Balkanski, Y.; Bauer, S.; Berntsen, T. K.; Bian, H.; Bellouin, N.; Chin, M.; Diehl, T.; Easter, R. C.; Feichter, J.; Ghan, S. J.; Hauglustaine, D.; Iversen, T.; Kinne, S.; Kirkevåg, A.; Lamarque, J.-F.; Lin, G.; Liu, X.; Lund, M. T.; Luo, G.; Ma, X.; van Noije, T.; Penner, J. E.; Rasch, P. J.; Ruiz, A.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Wang, P.; Wang, Z.; Xu, L.; Yu, H.; Yu, F.; Yoon, J.-H.; Zhang, K.; Zhang, H.; Zhou, C.

    2013-02-01

    We report on the AeroCom Phase II direct aerosol effect (DAE) experiment where 16 detailed global aerosol models have been used to simulate the changes in the aerosol distribution over the industrial era. All 16 models have estimated the radiative forcing (RF) of the anthropogenic DAE, and have taken into account anthropogenic sulphate, black carbon (BC) and organic aerosols (OA) from fossil fuel, biofuel, and biomass burning emissions. In addition several models have simulated the DAE of anthropogenic nitrate and anthropogenic influenced secondary organic aerosols (SOA). The model simulated all-sky RF of the DAE from total anthropogenic aerosols has a range from -0.58 to -0.02 Wm-2, with a mean of -0.27 Wm-2 for the 16 models. Several models did not include nitrate or SOA and modifying the estimate by accounting for this with information from the other AeroCom models reduces the range and slightly strengthens the mean. Modifying the model estimates for missing aerosol components and for the time period 1750 to 2010 results in a mean RF for the DAE of -0.35 Wm-2. Compared to AeroCom Phase I (Schulz et al., 2006) we find very similar spreads in both total DAE and aerosol component RF. However, the RF of the total DAE is stronger negative and RF from BC from fossil fuel and biofuel emissions are stronger positive in the present study than in the previous AeroCom study. We find a tendency for models having a strong (positive) BC RF to also have strong (negative) sulphate or OA RF. This relationship leads to smaller uncertainty in the total RF of the DAE compared to the RF of the sum of the individual aerosol components. The spread in results for the individual aerosol components is substantial, and can be divided into diversities in burden, mass extinction coefficient (MEC), and normalized RF with respect to AOD. We find that these three factors give similar contributions to the spread in results.

  16. Fusing Simulation Results From Multifidelity Aero-servo-elastic Simulators - Application To Extreme Loads On Wind Turbine

    DEFF Research Database (Denmark)

    Abdallah, Imad; Sudret, Bruno; Lataniotis, Christos

    2015-01-01

    bending moment at the blade root of a large wind turbine as a function of wind speed, turbulence and shear exponent in the presence of model uncertainty and non-stationary noise in the output. The extreme responses are obtained by two widely accepted numerical aero-servo-elastic simulators, FAST......Fusing predictions from multiple simulators in the early stages of the conceptual design of a wind turbine results in reduction in model uncertainty and risk mitigation. Aero-servo-elastic is a term that refers to the coupling of wind inflow, aerodynamics, structural dynamics and controls. Fusing...

  17. Aerosciences, Aero-Propulsion and Flight Mechanics Technology Development for NASA's Next Generation Launch Technology Program

    Science.gov (United States)

    Cockrell, Charles E., Jr.

    2003-01-01

    The Next Generation Launch Technology (NGLT) program, Vehicle Systems Research and Technology (VSR&T) project is pursuing technology advancements in aerothermodynamics, aeropropulsion and flight mechanics to enable development of future reusable launch vehicle (RLV) systems. The current design trade space includes rocket-propelled, hypersonic airbreathing and hybrid systems in two-stage and single-stage configurations. Aerothermodynamics technologies include experimental and computational databases to evaluate stage separation of two-stage vehicles as well as computational and trajectory simulation tools for this problem. Additionally, advancements in high-fidelity computational tools and measurement techniques are being pursued along with the study of flow physics phenomena, such as boundary-layer transition. Aero-propulsion technology development includes scramjet flowpath development and integration, with a current emphasis on hypervelocity (Mach 10 and above) operation, as well as the study of aero-propulsive interactions and the impact on overall vehicle performance. Flight mechanics technology development is focused on advanced guidance, navigation and control (GN&C) algorithms and adaptive flight control systems for both rocket-propelled and airbreathing vehicles.

  18. Physics and Measurement of Aero-Optical Effects: Past and Present

    Science.gov (United States)

    Jumper, Eric J.; Gordeyev, Stanislav

    2017-01-01

    The field of aero-optics is devoted to the study of the effects of turbulent flow fields on laser beams projected from airborne laser systems. This article reviews the early and present periods of research in aero-optics. Both periods generated impressive amounts of research activity; however, the types and amount of data differ greatly in accuracy, quality, and type owing to the development of new types of instrumentation available to collect and analyze the aberrated wave fronts of otherwise collimated laser beams projected through turbulent compressible flow fields of the type that form over beam directors. This review traces the activities and developments associated with both periods but particularly focuses on the development of modern high-bandwidth wave-front sensors used in the present research period. We describe how these modern wave-front data are collected and analyzed and the fluid mechanic information that can be gleaned from them; the use of these data in the fundamental study of turbulence is emphasized.

  19. Digital holographic interferometry for characterizing deformable mirrors in aero-optics

    Science.gov (United States)

    Trolinger, James D.; Hess, Cecil F.; Razavi, Payam; Furlong, Cosme

    2016-08-01

    Measuring and understanding the transient behavior of a surface with high spatial and temporal resolution are required in many areas of science. This paper describes the development and application of a high-speed, high-dynamic range, digital holographic interferometer for high-speed surface contouring with fractional wavelength precision and high-spatial resolution. The specific application under investigation here is to characterize deformable mirrors (DM) employed in aero-optics. The developed instrument was shown capable of contouring a deformable mirror with extremely high-resolution at frequencies exceeding 40 kHz. We demonstrated two different procedures for characterizing the mechanical response of a surface to a wide variety of input forces, one that employs a high-speed digital camera and a second that employs a low-speed, low-cost digital camera. The latter is achieved by cycling the DM actuators with a step input, producing a transient that typically lasts up to a millisecond before reaching equilibrium. Recordings are made at increasing times after the DM initiation from zero to equilibrium to analyze the transient. Because the wave functions are stored and reconstructable, they can be compared with each other to produce contours including absolute, difference, and velocity. High-speed digital cameras recorded the wave functions during a single transient at rates exceeding 40 kHz. We concluded that either method is fully capable of characterizing a typical DM to the extent required by aero-optical engineers.

  20. Aero-engine fault diagnosis applying new fast support vector algorithm

    Institute of Scientific and Technical Information of China (English)

    XU Qi-hua; GENG Shuai; SHI Jun

    2012-01-01

    A new fast learning algorithm was presented to solve the large-scale support vector machine ( SVM ) training problem of aero-engine fault diagnosis.The relative boundary vectors ( RBVs ) instead of all the original training samples were used for the training of the binary SVM fault classifiers.This pruning strategy decreased the number of final training sample significantly and can keep classification accuracy almost invariable.Accordingly , the training time was shortened to 1 / 20compared with basic SVM classifier.Meanwhile , owing to the reduction of support vector number , the classification time was also reduced.When sample aliasing existed , the aliasing sample points which were not of the same class were eliminated before the relative boundary vectors were computed.Besides , the samples near the relative boundary vectors were selected for SVM training in order to prevent the loss of some key sample points resulted from aliasing.This can improve classification accuracy effectively.A simulation example to classify 5classes of combination fault of aero-engine gas path components was finished and the total fault classification accuracy reached 96.1%.Simulation results show that this fast learning algorithm is effective , reliable and easy to be implemented for engineering application.

  1. Aero-optic analysis of anisotropic turbulent boundary layer by direct integration

    Science.gov (United States)

    Taylor, S.; Price, J.; Chen, C. P.; Pond, John E.; Sutton, G. W.

    2013-09-01

    Aero-optic aberrations that effect optical sensor performance and laser beam propagation, can be caused by changes in the index-of-refraction field as the optical wave traverses a compressible non-uniform, turbulent flowfield. Mean flowfield non-uniformities cause bore sight error and blurring and, if the mean flowfield is unsteady, jitter. Turbulence causes blurring and high frequency jitter. Blurring also causes the signal-to-noise ratio to decrease and image distortion, and adversely affects centroid location for precision tracking. The objective of this study is to develop an unified approach for whole-field aero-optics prediction using hybrid LES/RANS (Large Eddy Simulation/Reynolds Average Navier-Stokes) turbulence modeling in combination with a newly formulated optical Modulation Transfer Function (MTF). The whole field turbulence includes the near-vehicle boundary layer mean and turbulence, as well as far-field atmospheric turbulence. A flat plate compressible boundary layer case is used to demonstrate the methodology. the abstract two lines below author names and addresses.

  2. Research and Development of Some Advanced High Temperature Titanium Alloys for Aero-engine

    Directory of Open Access Journals (Sweden)

    CAI Jian-ming

    2016-08-01

    Full Text Available Some advanced high temperature titanium alloys are usually selected to be manufactured into blade, disc, case, blisk and bling under high temperature environment in compressor and turbine system of a new generation high thrust-mass ratio aero-engine. The latest research progress of 600℃ high temperature titanium alloy, fireproof titanium alloy, TiAl alloy, continuous SiC fiber reinforced titanium matrix composite and their application technology in recent years in China were reviewed in this paper. The key technologies need to be broken through in design, processing and application of new material and component are put forward, including industrial ingot composition of high purified and homogeneous control technology, preparation technology of the large size bar and special forgings, machining technology of blisk and bling parts, material property evaluation and application design technique. The future with the continuous application of advanced high temperature titanium alloys, will be a strong impetus to the development of China's aero-engine technology.

  3. Implications of the homogeneous turbulence assumption on the aero-optic linking equation

    Science.gov (United States)

    Hugo, Ronald J.; Jumper, Eric J.

    1995-09-01

    This paper investigates the validity of applying the simplified (under the assumptions of isotropic and homogeneous turbulence) aero-optic linking equation to a flowfield that is known to consist of anisotropic and nonhomogeneous turbulence. The investigation is performed in the near nozzle-region of a heated two-dimensional jet, and the study makes use of a conditional sampling experiment to acquire a spatio-temporal temperature field data base for the heated jet flowfield. After compensating for the bandwidth limitations of constant-current-wire temperature measurements, the temperature field data base is applied to the computation of optical degradation through both direct methods and indirect methods relying on the aero-optic linking equation. The simplified version of the linking equation was found to provide very good agreement with direct calculations provided that the length scale of the density fluctuations was interpreted as being the integral scale, with the limits of the integration being the two first zero crossings of the covariance coefficient function.

  4. Applicability of the Aero-Optic Linking Equation to a Highly Coherent, Transitional Shear Layer

    Science.gov (United States)

    Hugo, Ronald J.; Jumper, Eric J.

    2000-08-01

    We investigate the validity of applying a simplified (under the assumptions of isotropic and homogeneous turbulence) aero-optic linking equation to a flow field that is known to consist of anisotropic and nonhomogeneous turbulence. The investigation is performed in the near-nozzle region of a heated two-dimensional jet, and the study makes use of a conditional-sampling experiment to acquire a spatiotemporal temperature field database for the heated-jet flow field. After compensating for the bandwidth limitations of constant-current wire temperature measurements, the temperature field database is applied to the computation of optical degradation through both direct and indirect methods, relying on the aero-optic linking equation. The simplified version of the linking equation was found to provide good agreement with direct calculations, provided that the length scale of the density fluctuations was interpreted as being the integral scale, with the limits of integration being the first two zero crossings of the covariance coefficient function.

  5. A Rapid Method to Achieve Aero-Engine Blade Form Detection

    Directory of Open Access Journals (Sweden)

    Bin Sun

    2015-06-01

    Full Text Available This paper proposes a rapid method to detect aero-engine blade form, according to the characteristics of an aero-engine blade surface. This method first deduces an inclination error model in free-form surface measurements based on the non-contact laser triangulation principle. Then a four-coordinate measuring system was independently developed, a special fixture was designed according to the blade shape features, and a fast measurement of the blade features path was planned. Finally, by using the inclination error model for correction of acquired data, the measurement error that was caused by tilt form is compensated. As a result the measurement accuracy of the Laser Displacement Sensor was less than 10 μm. After the experimental verification, this method makes full use of optical non-contact measurement fast speed, high precision and wide measuring range of features. Using a standard gauge block as a measurement reference, the coordinate system conversion data is simple and practical. It not only improves the measurement accuracy of the blade surface, but also its measurement efficiency. Therefore, this method increases the value of the measurement of complex surfaces.

  6. The Chaotic Prediction for Aero-Engine Performance Parameters Based on Nonlinear PLS Regression

    Directory of Open Access Journals (Sweden)

    Chunxiao Zhang

    2012-01-01

    Full Text Available The prediction of the aero-engine performance parameters is very important for aero-engine condition monitoring and fault diagnosis. In this paper, the chaotic phase space of engine exhaust temperature (EGT time series which come from actual air-borne ACARS data is reconstructed through selecting some suitable nearby points. The partial least square (PLS based on the cubic spline function or the kernel function transformation is adopted to obtain chaotic predictive function of EGT series. The experiment results indicate that the proposed PLS chaotic prediction algorithm based on biweight kernel function transformation has significant advantage in overcoming multicollinearity of the independent variables and solve the stability of regression model. Our predictive NMSE is 16.5 percent less than that of the traditional linear least squares (OLS method and 10.38 percent less than that of the linear PLS approach. At the same time, the forecast error is less than that of nonlinear PLS algorithm through bootstrap test screening.

  7. A Co-modeling Method Based on Component Features for Mechatronic Devices in Aero-engines

    Science.gov (United States)

    Wang, Bin; Zhao, Haocen; Ye, Zhifeng

    2017-08-01

    Data-fused and user-friendly design of aero-engine accessories is required because of their structural complexity and stringent reliability. This paper gives an overview of a typical aero-engine control system and the development process of key mechatronic devices used. Several essential aspects of modeling and simulation in the process are investigated. Considering the limitations of a single theoretic model, feature-based co-modeling methodology is suggested to satisfy the design requirements and compensate for diversity of component sub-models for these devices. As an example, a stepper motor controlled Fuel Metering Unit (FMU) is modeled in view of the component physical features using two different software tools. An interface is suggested to integrate the single discipline models into the synthesized one. Performance simulation of this device using the co-model and parameter optimization for its key components are discussed. Comparison between delivery testing and the simulation shows that the co-model for the FMU has a high accuracy and the absolute superiority over a single model. Together with its compatible interface with the engine mathematical model, the feature-based co-modeling methodology is proven to be an effective technical measure in the development process of the device.

  8. Coupling behavior between adhesive and abrasive wear mechanism of aero-hydraulic spool valves

    Institute of Scientific and Technical Information of China (English)

    Chen Yunxia; Gong Wenjun; Kang Rui

    2016-01-01

    Leakage due to wear is one of the main failure modes of aero-hydraulic spool valves. This paper established a practical coupling wear model for aero-hydraulic spool valves based on dynamic system modelling theory. Firstly, the experiment for wear mechanism verification proved that adhesive wear and abrasive wear did coexist during the working process of spool valves. Sec-ondly coupling behavior of each wear mechanism was characterized by analyzing actual time-variation of model parameters during wear evolution process. Meanwhile, Archard model and three-body abrasive wear model were utilized for adhesive wear and abrasive wear, respectively. Furthermore, their coupling wear model was established by calculating the actual wear volume. Finally, from the result of formal test, all the required parameters for our model were obtained. The relative error between model prediction and data of pre-test was also presented to verify the accuracy of model, which demonstrated that our model was useful for providing accurate prediction of spool valve’s wear life.

  9. Aero-acoustics in a tangential blower: validation of the CFD flow distribution using advanced PIV techniques

    Directory of Open Access Journals (Sweden)

    Jean-Yves Noël

    2007-12-01

    Full Text Available Noise reduction is of increasing importance in the community. Consequently, the development of aero-acoustics is gaining special focus within industry. Computational Aero-Acoustics (CAA, the coupling of Computational Fluid Dynamics (CFD and Computational Acoustics (CA, is being used in the design and assessment of a range of products from HVAC ducts to domestic appliances. The process for carrying out an Aero-Acoustic simulation begins with the solution of the transient flow dynamics in order to compute accurately the pressure fluctuations at a number of points in the computational domain. These fluctuations are passed to the acoustic code to propagate the acoustic waves through the system and determine its acoustic signature. To minimize errors in the acoustic propagation analysis it is thus essential that accurate predictions of the noise sources be obtained. This paper concentrates on the CFD part of the aero-acoustic simulation. The case considered has been taken from the European project DESTINY:3 and comprises a tangential blower located inside a complex duct system. Air is drawn into the fan through two inlets and exits through a single duct. The computational methodology and flow field predictions are presented and compared to experimental PIV data. The numerical predictions were found to be in good agreement with the experimental data, reproducing the asymmetries in the flow field.

  10. 76 FR 67243 - In the Matter of Accesspoint Corp., Aero Performance Products, Inc., Apex Resources Group, Inc...

    Science.gov (United States)

    2011-10-31

    ... COMMISSION In the Matter of Accesspoint Corp., Aero Performance Products, Inc., Apex Resources Group, Inc., Aradyme Corp., Bancroft Uranium, Inc., Fightersoft Multimedia Corp., Fortress Financial Group, Inc., and... Resources Group, Inc. because it has not filed any periodic reports since the period ended March 31,...

  11. 76 FR 72235 - Abviva, Inc., ACTIS Global Ventures, Inc., aeroTelesis, Inc., Amwest Insurance Group, Inc., and...

    Science.gov (United States)

    2011-11-22

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Abviva, Inc., ACTIS Global Ventures, Inc., aeroTelesis, Inc., Amwest Insurance Group, Inc., and... information concerning the securities of ACTIS Global Ventures, Inc. because it has not filed any...

  12. 75 FR 22512 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-04-29

    ... Industries S.p.A. Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of....regulations.gov ; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through... 2. The FAA amends Sec. 39.13 by adding the following new AD: 2010-09-09 Piaggio Aero Industries...

  13. 76 FR 10224 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2011-02-24

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... this AD, contact Piaggio Aero Industries S.p.A., Via Cibrario, 4-16154 Genoa, Italy; phone: +39 010... that the towing bar P/N 01-1227-0000 or similar ferromagnetic masses are prohibited to be carried...

  14. 75 FR 63058 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-10-14

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of....regulations.gov ; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through... 2. The FAA amends Sec. 39.13 by adding the following new AD: 2010-21-14 PIAGGIO AERO INDUSTRIES...

  15. 76 FR 7694 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2011-02-11

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The..., etc. for PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 airplanes. As published, the...

  16. 75 FR 68172 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-11-05

    ... Industries S.p.A. Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... identified in this AD, contact Piaggio Aero Industries S.p.a., Via Cibrario, 4-16154 Genoa, Italy; phone: +39... between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the...

  17. 75 FR 67639 - Airworthiness Directives; Piaggio Aero Industries S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-11-03

    ... Industries S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... Airplane Flight Manual, stating that the towing bar P/N 01-1227-0000 or similar ferromagnetic masses are... maintenance requirements and/or airworthiness limitations developed by Piaggio Aero Industries S.p.A....

  18. Aero-optical effects of an optical seeker with a supersonic jet for hypersonic vehicles in near space.

    Science.gov (United States)

    Guo, Guangming; Liu, Hong; Zhang, Bin

    2016-06-10

    The aero-optical effects of an optical seeker with a supersonic jet for hypersonic vehicles in near space were investigated by three suites of cases, in which the altitude, angle of attack, and Mach number were varied in a large range. The direct simulation Monte Carlo based on the Boltzmann equation was used for flow computations and the ray-tracing method was used to simulate beam transmission through the nonuniform flow field over the optical window. Both imaging displacement and phase deviation were proposed as evaluation parameters, and along with Strehl ratio they were used to quantitatively evaluate aero-optical effects. The results show that aero-optical effects are quite weak when the altitude is greater than 30 km, the imaging displacement is related to the incident angle of a beam, and it is minimal when the incident angle is approximately 15°. For reducing the aero-optical effects, the optimal location of an aperture should be in the middle of the optical window.

  19. An AeroCom assessment of black carbon in Arctic snow and sea ice

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, C.; Flanner, M. G.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Berntsen, T. K.; Bian, H.; Carslaw, K. S.; Chin, M.; De Luca, N.; Diehl, T.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Koch, D.; Liu, X.; Mann, G. W.; Penner, J. E.; Pitari, G.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Steenrod, S. D.; Stier, P.; Takemura, T.; Tsigaridis, K.; van Noije, T.; Yun, Y.; Zhang, K.

    2014-01-01

    Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea ice. In this paper, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within-snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004 to 2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are -4.4 (-13.2 to +10.7) ng g-1 for an earlier phase of AeroCom models (phase I), and +4.1 (-13.0 to +21.4) ng g-1 for a more recent phase of AeroCom models (phase II), compared to the observational mean of 19.2 ng g-1. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model–measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60–90° N) atmospheric residence time for BC in phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with

  20. An AeroCom Assessment of Black Carbon in Arctic Snow and Sea Ice

    Science.gov (United States)

    Jiao, C.; Flanner, M. G.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Bernsten, T. K.; Bian, H.; Carslaw, K. S.; Chin, M.; DeLuca, N.; Diehl, T.; Ghan, S. J.; Iversen, T.; Kirkevag, A.; Koch, D.; Liu, X.; Mann, G. W.; Penner, J. E.; Pitari, G.; Schulz, M.; Seland, O; Skeie, R. B.; Steenrod, S. D.; Stier, P.; Tkemura, T.

    2014-01-01

    Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea ice. Here, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within-snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004 to 2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are -4.4 (-13.2 to +10.7) ng/g for an earlier phase of AeroCom models (phase I), and +4.1 (-13.0 to +21.4) ng/g for a more recent phase of AeroCom models (phase II), compared to the observational mean of 19.2 ng/g. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model-measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60-90degN) atmospheric residence time for BC in phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with the fact that most Arctic BC deposition originates

  1. An overview of aeroelasticity studies for the National Aero-Space Plane

    Science.gov (United States)

    Ricketts, Rodney H.; Noll, Thomas E.; Whitlow, Woodrow, Jr.; Huttsell, Lawrence J.

    1993-01-01

    The National Aero-Space Plane (NASP), or X-30, is a single-stage-to-orbit vehicle that is designed to takeoff and land on conventional runways. Research in aeroelasticity was conducted by the NASA and the Wright Laboratory to support the design of a flight vehicle by the national contractor team. This research includes the development of new computational codes for predicting unsteady aerodynamic pressures. In addition, studies were conducted to determine the aerodynamic heating effects on vehicle aeroelasticity and to determine the effects of fuselage flexibility on the stability of the control systems. It also includes the testing of scale models to better understand the aeroelastic behavior of the X-30 and to obtain data for code validation and correlation. This paper presents an overview of the aeroelastic research which has been conducted to support the airframe design.

  2. Evaluations on aero-optic effects of subsonic airborne electro-optical system

    Institute of Scientific and Technical Information of China (English)

    Kexin Yin; Huilin Jiang

    2006-01-01

    @@ A simple method based on CFD code and Matlab for aero-optic effects is presented. Density fluctuation from CFD code due to the changes of such factors as altitude, speed, equipment location, and wavelength is introduced as an input to Matlab. The overall calculations are in Matlab. The results show that the performance of electro-optical (EO) system can be improved when the altitude increasing, the speed is as slowly as possible, and the equipment location moves to the leading edge of the airborne platform as far as possible, for the wavelength there is an optimum one when the indexes of contrast and resolution of the system are both considered. All of these methods can minimize the optical aberrations. Several numerical simulations demonstrate the method.

  3. Emergency aero-photo survey after the 5.12 Wenchuan Earthquake, China

    Institute of Scientific and Technical Information of China (English)

    WANG ZhiHua; XU QiDe; XU Bin; ZHANG Wei

    2009-01-01

    After the 5.12 Wenchuan Earthquake which took place on May 12, 2000, aerial remote sensing has rapidly covered all the influence sites of the earthquake, emergency aero-photo interpretation has revealed the disaster distribution limitation, and captured the information of location, dimension of the destroyed houses, roads and other structures, blocked rivers, etc, which provided destroying conditions of the time for rescuing lives, rebuilding traffic lines and estimating disaster situation. The further interpretation and analysis indicate that large scale second growth geological disasters mainly distribute in the distance of 0-300 km and 45°-50° orientation from the epicenter. About 137 latent large-scale landslides and debris-flows will occur in this rain season and coming several years, so how to avoid current geological disasters as well as the latent large disasters should be considered in making rebuilding and developing plan.

  4. Verification of aero-elastic offshore wind turbine design codes under IEA Wind Task XXIII

    DEFF Research Database (Denmark)

    Vorpahl, Fabian; Strobel, Michael; Jonkman, Jason M.

    2014-01-01

    , a tripod and a floating spar buoy—the latest support structure developments in the offshore wind energy industry are covered, and an adaptation of the codes to those developments was initiated. The comparisons, in general, agreed quite well. Differences existed among the predictions were traced back......This work presents the results of a benchmark study on aero-servo-hydro-elastic codes for offshore wind turbine dynamic simulation. The codes verified herein account for the coupled dynamic systems including the wind inflow, aerodynamics, elasticity and controls of the turbine, along...... to differences in the model fidelity, aerodynamic implementation, hydrodynamic load discretization and numerical difficulties within the codes. The comparisons resulted in a more thorough understanding of the modeling techniques and better knowledge of when various approximations are not valid.More importantly...

  5. The neutral atmosphere temperature experiment. [for thermospheric nitrogen measurement on AEROS satellite

    Science.gov (United States)

    Spencer, N. W.; Pelz, D. T.; Niemann, H. B.; Carignan, G. R.; Caldwell, J. R.

    1974-01-01

    The AEROS Neutral Atmosphere Temperature Experiment (NATE) is designed to measure the kinetic temperature of molecular nitrogen in the thermosphere. A quadrupole mass spectrometer tuned to N2 measures the N2 density variation in a small spherical antechamber having a knife-edged orifice which is exposed to the atmosphere at the outer surface of the spacecraft. The changing density of N2 due to the spinning motion of the spacecraft permits determination of the velocity distribution of the N2 from which the temperature is calculated. An alternate mode of operation of the instrument allows measurement of the other gases in the atmosphere as well as N2 permitting determination of the neutral particle composition of the atmosphere.

  6. Experimental and Numerical Correlation of Impact of Spherical Projectile for Damage Analysis of Aero Engine Component

    Directory of Open Access Journals (Sweden)

    Anuradha Nayak Majila

    2016-03-01

    Full Text Available Studies the impact response of flat Titanium alloy plate against spherical projectile for damage analysis of aero engine components using experimental and finite element techniques. Compressed gas gun has been used to impart speed to spherical projectile at various impact velocities for damage studies. Crater dimensions (diameter and depth obtained due to impact have been compared with finite element results using commercially available explicit finite element method code LS-DYNA. Strain hardening, high strain rate and thermal softening effect along with damage parameters have been considered using modified Johnson-Cook material model of LS-DYNA. Metallographic analysis has been performed on the indented specimen. This analysis is useful to study failure analysis of gas turbine engine components subjected to domestic object damage of gas turbine engine. Defence Science Journal, Vol. 66, No. 2, March 2016, pp. 193-199, DOI: http://dx.doi.org/10.14429/dsj.66.9130

  7. Unified Multi-speed analysis (UMA) for the condition monitoring of aero-engines

    Science.gov (United States)

    Nembhard, Adrian D.; Sinha, Jyoti K.

    2015-12-01

    For rotating machinery in which speeds and dynamics constantly change, performing vibration-based condition monitoring can be challenging. Thus, an effort is made here to develop a Unified Multi-speed fault diagnosis technique that can exploit useful vibration information available at various speeds from a rotating machine in a single analysis. Commonly applied indicators are computed from data collected from a rig at different speeds for a baseline case and different faults. Four separate analyses are performed: single speed at a single bearing, integrated features from multiple speeds at a single bearing, single speed for integrated features from multiple bearings and the proposed Unified Multi-speed analysis. The Unified Multi-speed approach produces the most conspicuous separation and isolation among the conditions tested. Observations made here suggest integration of more dynamic features available at different speeds improves the learning process of the tool which could prove useful for aero-engine condition monitoring.

  8. Propulsion System Dynamic Modeling of the NASA Supersonic Concept Vehicle for AeroPropulsoServoElasticity

    Science.gov (United States)

    Kopasakis, George; Connolly, Joseph W.; Seiel, Jonathan

    2016-01-01

    A summary of the propulsion system modeling under NASA's High Speed Project (HSP) AeroPropulsoServoElasticity (APSE) task is provided with a focus on the propulsion system for the low-boom supersonic configuration developed by Lockheed Martin and referred to as the N+2 configuration. This summary includes details on the effort to date to develop computational models for the various propulsion system components. The objective of this paper is to summarize the model development effort in this task, while providing more detail in the modeling areas that have not been previously published. The purpose of the propulsion system modeling and the overall APSE effort is to develop an integrated dynamic vehicle model to conduct appropriate unsteady analysis of supersonic vehicle performance. This integrated APSE system model concept includes the propulsion system model, and the vehicle structural aerodynamics model. The development to date of such a preliminary integrated model will also be summarized in this report

  9. Aero-Acoustics of Modern Transonic Fans—Fan Noise Reduction from Its Sources

    Institute of Scientific and Technical Information of China (English)

    L. Xu; J.D. Denton

    2003-01-01

    The noise of aerodynamics nature from modern transonic fan is examined from its sources with the perspective of noise reduction through aero-acoustics design using advanced Computational Fluid Dynamics (CFD) tools.In particular the problems associated with the forward propagating noise in the front is addressed. It is identified that the shock wave spillage from the leading edge near the fan tip is the main source of the tone noise. Two different approaches have been studied to reduce the forward arc tone noise and two state-of-art transonic fans are designed using the strategies developed. The following rig tests show that while the fans exhibit other noise problems,the primary goals of noise reduction have been achieved through both fans and the novel noise reduction concept vindicated.

  10. Emergency aero-photo survey after the 5.12 Wenchuan Earthquake, China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    After the 5.12 Wenchuan Earthquake which took place on May 12, 2008, aerial remote sensing has rapidly covered all the influence sites of the earthquake, emergency aero-photo interpretation has re- vealed the disaster distribution limitation, and captured the information of location, dimension of the destroyed houses, roads and other structures, blocked rivers, etc, which provided destroying condi- tions of the time for rescuing lives, rebuilding traffic lines and estimating disaster situation. The further interpretation and analysis indicate that large scale second growth geological disasters mainly dis- tribute in the distance of 0―300 km and 45°―50° orientation from the epicenter. About 137 latent large-scale landslides and debris-flows will occur in this rain season and coming several years, so how to avoid current geological disasters as well as the latent large disasters should be considered in making rebuilding and developing plan.

  11. Methodologies for predicting the part-load performance of aero-derivative gas turbines

    DEFF Research Database (Denmark)

    Haglind, Fredrik; Elmegaard, Brian

    2009-01-01

    on methodologies for predicting part-load performance of aero-derivative gas turbines. Two different design models – one simple and one more complex – are created. Subsequently, for each of these models, the part-load performance is predicted using component maps and turbine constants, respectively. Comparisons...... with manufacturer data are made. With respect to the design models, the simple model, featuring a compressor, combustor and turbines, results in equally good performance prediction in terms of thermal efficiency and exhaust temperature as does a more complex model. As for part-load predictions, the results suggest...... that the mass flow and pressure ratio characteristics can be well predicted with both methods. The thermal efficiency and exhaust temperature, however, are not well predicted below 60–70% load when using turbine constants and assuming constant efficiencies for turbomachinery....

  12. Presentations from the Aeroelastic Workshop - latest results from AeroOpt

    Energy Technology Data Exchange (ETDEWEB)

    Hartvig Hansen, M. (ed.)

    2011-10-15

    This report contains the slides of the presentations at the Aeroelastic Workshop held at Risoe-DTU for the wind energy industry in Denmark on October 27, 2011. The scientific part of the agenda at this workshop was 1) Detailed and reduced models of dynamic mooring system (Anders M. Hansen). 2) Bend-twist coupling investigation in HAWC2 (Taeseong Kim). 3) Q3UIC - A new aerodynamic airfoil tool including rotational effects (Nestor R. Garcia). 4) Influence of up-scaling on loads, control and aerodynamic modeling (Helge Aa. Madsen). 5) Aerodynamic damping of lateral tower vibrations (Bjarne S. Kallesoee). 6) Open- and closed-loop aeroservoelastic analysis with HAWCStab2 (Morten H. Hansen). 7) Design and test of a thick, flatback, high-lift multielement airfoil (Frederik Zahle). The presented results are mainly obtained in the EUDP project ''Aeroelastic Optimization of MW Wind Turbines (AeroOpt)''. (Author)

  13. C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 1: Concepts of Use, Initial System Requirements, Architecture, and AeroMACS Design Considerations

    Science.gov (United States)

    Hall, Edward; Isaacs, James; Henriksen, Steve; Zelkin, Natalie

    2011-01-01

    This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I (this document) is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

  14. C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 2: Test Bed Performance Evaluation and Final AeroMACS Recommendations

    Science.gov (United States)

    Hall, Edward; Magner, James

    2011-01-01

    This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II (this document) describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

  15. Reconstruction of the aero-mixture channels of the pulverized coal plant of the 100MW power plant unit

    Directory of Open Access Journals (Sweden)

    Ivanovic Vladan B.

    2011-01-01

    Full Text Available After the last revitalization of thermal power block of 100 MW in TPP “Kostolac A”, made in the year 2004, during the operation of the plant, pulverized coal deposition often occurred in horizontal sections of the aero-mixture channels. Deposition phenomenon manifested itself in places ahead of spherical compensators in the direction of flow of pulverized coal to the burners, due to unfavorable configuration of these channels. Coal dust deposited in the channels dried and spontaneously combusted, causing numerous damage to channels and its isolation as well as the frequent stoppage of the operation for necessary interventions. The paper presents the original solution of reconstruction of aero-mixture channels which prevented deposition of coal dust and its eventual ignition. In this way the reliability of the mill plant is maximized and higher availability of boiler and block as a whole is achieved.

  16. CONSIDERATIONS ON ANATOMY AND PHYSIOLOGY OF LYMPH VESSELS OF UPPER AERO DIGESTIVE ORGANS AND CERVICAL SATELLITE LYMPH NODE GROUP.

    Science.gov (United States)

    Ciupilan, Corina; Stan, C I

    2016-01-01

    The almost constant local regional development of the cancers of upper aero digestive organs requires the same special attention to cervical lymph node metastases, as well as to the primary neoplastic burning point. The surgical therapy alone or associated has a mutilating, damaging character, resulting in loss of an organ and function, most of the times with social implications, involving physical distortions with aesthetic consequences, which make the reintegration of the individual into society questionable. The problem of cervical lymph node metastases is vast and complex, reason why we approached several anatomical and physiological aspects of lymph vessels of the aero digestive organs. Among the available elements during treatment, the headquarters of the tumour, its histologic degree, and its infiltrative nature, each of them significantly influences the possibility of developing metastases.

  17. Some Issues Relating to Design and Development of an All-Composite Aero Gas Turbine Engine Rotor

    Directory of Open Access Journals (Sweden)

    K. Gupta

    1998-01-01

    Full Text Available The paper addresses some of the issues involved in the development of an all-composite aero gasturbine engine rotor with a view to reducing the total engine weight and increasing the thrust-weightratio beyond 20: I. It identifies the materials to be used for different components, i.e. shafts, discs andblades in the high and iow temperature regions. The various problems anticipated in its developmentare discussed and solutions recommended, wherever possible.

  18. Fusing Simulation Results From Multifidelity Aero-servo-elastic Simulators - Application To Extreme Loads On Wind Turbine

    DEFF Research Database (Denmark)

    Abdallah, Imad; Sudret, Bruno; Lataniotis, Christos

    2015-01-01

    bending moment at the blade root of a large wind turbine as a function of wind speed, turbulence and shear exponent in the presence of model uncertainty and non-stationary noise in the output. The extreme responses are obtained by two widely accepted numerical aero-servo-elastic simulators, FAST...... and BLADED. With limited high-fidelity response samples, the co-Kriging model produced notably accurate prediction of validation data....

  19. Cost effective aero-photogrammetry toys at active volcanoes: On the use of drones, balloons and kites

    Science.gov (United States)

    Walter, Thomas R.

    2014-05-01

    The availability of aerial photographs allows spatial mapping of flows and fractures, generation of digital elevation models and other change detection. Therefore aerial photographs significantly improve our understanding of volcanic processes. The common problem is the lack of available data for most volcanoes, and the lack of systematic and chronologic repeat surveys. This work summarizes the current state of knowledge and technical implementations that currently revolutionize the field of aero-photogrammetry. By the use of unmanned vehicles, such as octocopters, helicopters and small airplanes, photo data can be acquired from almost any place at distances up to kilometres from the operator. Moreover, by the use of helium balloons, kites or their hybrid helikites, near field aero-photographs are obtained. In combination with modern stitching procedures and computer vision algorithms, the positioning of the camera and the digital elevation model of the ground can be extracted, and the active volcano and its eruption cloud be imaged from almost any perspective. This field is increasingly gaining flexibility, as lightweight cameras are available from visible, infrared and other spectral bands. Here example data are provided from volcanoes that are difficult to access by regular airplanes, showing the strengths and the limits of these new aero-photogrammetry toys.

  20. Adaptive-optic approach to mitigating aero-optic disturbances for a forced shear layer

    Science.gov (United States)

    Nightingale, Alice M.

    Non-uniform, variable-density fields, resulting from compressibility effects in turbulent flows, are the source of aero-optical distortions which cause significant reductions in optical system performance. As a laser beam transverses through an optically active medium, containing index-of-refraction variations, several optical phenomena occur including beam wander, image distortion, and beam defocus. When encountering a variation in the index field, light waves refract causing an otherwise planar wavefront of a laser beam to become aberrated, contributing to the adverse effects mentioned above. Adaptive-Optics (AO) is a technique used to correct for such spatially and temporally varying aberrations on an optical beam by applying a conjugate waveform correction prior to the beams transmission through the flow. Conventional AO systems are bandwidth limited by real-time processing issues and wavefront sensor limitations. Therefore, an alternative to the conventional AO approach has been proposed, developed and evaluated with the goal of overcoming such bandwidth limitations. The alternative AO system, presented throughout this document, consists of two main features; feed-forward flow control and a phase-locked-loop AO control strategy. Initially irregular, unpredictable large-scale structures within a shear layer are regularized using flow control. Subsequently, the resulting optical wavefront, and corresponding optical signal, emerging from the regularized flow becomes more periodic and predictable effectively reducing the bandwidth necessary to make real-time corrections. A phase-lock-loop controller is then used to perform real-time corrections. Wavefront corrections are estimated based upon the regularized flow, while two small aperture laser beams provide a non-intrusive means of acquiring amplitude and phase error measurements. The phase-lock-loop controller uses these signals as feedback to synchronize the deformable mirror's waveform to that of the shear

  1. CFD predictions of LBO limits for aero-engine combustors using fuel iterative approximation

    Institute of Scientific and Technical Information of China (English)

    Hu Bin; Huang Yong; Wang Fang; Xie Fa

    2013-01-01

    Lean blow-out (LBO) is critical to operational performance of combustion systems in propulsion and power generation.Current predictive tools for LBO limits are based on decadesold empirical correlations that have limited applicability for modern combustor designs.According to the Lefebvre's model for LBO and classical perfect stirred reactor (PSR) concept,a load parameter (LP) is proposed for LBO analysis of aero-engine combustors in this paper.The parameters contained in load parameter are all estimated from the non-reacting flow field of a combustor that is obtained by numerical simulation.Additionally,based on the load parameter,a method of fuel iterative approximation (FIA) is proposed to predict the LBO limit of the combustor.Compared with experimental data for 19 combustors,it is found that load parameter can represent the actual combustion load of the combustor near LBO and have good relativity with LBO fuel/air ratio (FAR).The LBO FAR obtained by FIA shows good agreement with experimental data,the maximum prediction uncertainty of FIA is about ± 17.5%.Because only the non-reacting flow is simulated,the time cost of the LBO limit prediction using FIA is relatively low (about 6 h for one combustor with computer equipment of CPU 2.66 GHz × 4 and 4 GB memory),showing that FIA is reliable and efficient to be used for practical applications.

  2. Dynamic behavior of aero-engine rotor with fusing design suffering blade off

    Directory of Open Access Journals (Sweden)

    Cun WANG

    2017-06-01

    Full Text Available Fan blade off (FBO from a running turbofan rotor will introduce sudden unbalance into the dynamical system, which will lead to the rub-impact, the asymmetry of rotor and a series of interesting dynamic behavior. The paper first presents a theoretical study on the response excited by sudden unbalance. The results reveal that the reaction force of the bearing located near the fan could always reach a very high value which may lead to the crush of ball, journal sticking, high stress on the other components and some other failures to endanger the safety of engine in FBO event. Therefore, the dynamic influence of a safety design named “fusing” is investigated by mechanism analysis. Meantime, an explicit FBO model is established to simulate the FBO event, and evaluate the effectiveness and potential dynamic influence of fusing design. The results show that the fusing design could reduce the vibration amplitude of rotor, the reaction force on most bearings and loads on mounts, but the sudden change of support stiffness induced by fusing could produce an impact effect which will couple with the influence of sudden unbalance. Therefore, the implementation of the design should be considered carefully with optimized parameters in actual aero-engine.

  3. Modeling simulation of the thermal radiation for high-speed flight vehicles' aero-optical windows

    Science.gov (United States)

    Chen, Lei; Zhang, Liqin; Guo, Mingjiang

    2015-10-01

    When high-speed flight vehicles fly in the atmosphere, they can generate serious aero-optical effect. The optical window temperature rises sharply because of aerodynamic heating. It will form radiation interference that can lead infrared detectors to producing non-uniform radiation backgrounds, decreasing system SNR and detection range. Besides, there exits temperature difference due to uneven heating. Under the thermo-optical and elastic-optical effects, optical windows change into inhomogeneous mediums which influence the ray propagation. In this paper, a model of thermal radiation effect was built by a finite element analysis method. Firstly, the optical window was divided into uniform grids. Then, radiation distribution on the focal planes at different angles of the window's normal line and optical axis was obtained by tracing light rays of each grid. Finally, simulation results indicate that radiation distribution reflects the two directions-the length and width-of temperature distribution, and the change of angle causes the center of radiation distribution to shift to one direction of the image surface under the same window temperature.

  4. Uncertainty of measurement for large product verification: evaluation of large aero gas turbine engine datums

    Science.gov (United States)

    Muelaner, J. E.; Wang, Z.; Keogh, P. S.; Brownell, J.; Fisher, D.

    2016-11-01

    Understanding the uncertainty of dimensional measurements for large products such as aircraft, spacecraft and wind turbines is fundamental to improving efficiency in these products. Much work has been done to ascertain the uncertainty associated with the main types of instruments used, based on laser tracking and photogrammetry, and the propagation of this uncertainty through networked measurements. Unfortunately this is not sufficient to understand the combined uncertainty of industrial measurements, which include secondary tooling and datum structures used to locate the coordinate frame. This paper presents for the first time a complete evaluation of the uncertainty of large scale industrial measurement processes. Generic analysis and design rules are proven through uncertainty evaluation and optimization for the measurement of a large aero gas turbine engine. This shows how the instrument uncertainty can be considered to be negligible. Before optimization the dominant source of uncertainty was the tooling design, after optimization the dominant source was thermal expansion of the engine; meaning that no further improvement can be made without measurement in a temperature controlled environment. These results will have a significant impact on the ability of aircraft and wind turbines to improve efficiency and therefore reduce carbon emissions, as well as the improved reliability of these products.

  5. Rotary-Wing Relevant Compressor Aero Research and Technology Development Activities at Glenn Research Center

    Science.gov (United States)

    Welch, Gerard E.; Hathaway, Michael D.; Skoch, Gary J.; Snyder, Christopher A.

    2012-01-01

    Technical challenges of compressors for future rotorcraft engines are driven by engine-level and component-level requirements. Cycle analyses are used to highlight the engine-level challenges for 3000, 7500, and 12000 SHP-class engines, which include retention of performance and stability margin at low corrected flows, and matching compressor type, axial-flow or centrifugal, to the low corrected flows and high temperatures in the aft stages. At the component level: power-to-weight and efficiency requirements impel designs with lower inherent aerodynamic stability margin; and, optimum engine overall pressure ratios lead to small blade heights and the associated challenges of scale, particularly increased clearance-to-span ratios. The technical challenges associated with the aerodynamics of low corrected flows and stability management impel the compressor aero research and development efforts reviewed herein. These activities include development of simple models for clearance sensitivities to improve cycle calculations, full-annulus, unsteady Navier-Stokes simulations used to elucidate stall, its inception, and the physics of stall control by discrete tip-injection, development of an actuator-duct-based model for rapid simulation of nonaxisymmetric flow fields (e.g., due inlet circumferential distortion), advanced centrifugal compressor stage development and experimentation, and application of stall control in a T700 engine.

  6. 3 D FEM analysis of welding residual stress and deformation of aero-engine blisk

    Institute of Scientific and Technical Information of China (English)

    杨建国; 周号; 雷靖; 方洪渊; 张学秋; 曲伸

    2014-01-01

    Aero-engine blisk welded by electron beam welding(EBW)method is a complicated structure.Fixtures were used to control the deformation ofblisk during its manufacturing process.Finite element method was utilized to study the evolution of the welding residual stress and deformation of this structure.In which an attenuation function was applied to the double ellipsoid heat source model based on the characteristic ofEBW,and the effects offixtures on the welding residual stresses and deforamtion were also reserached.The simulation results showed that the temperature contour ofweld cross section vertical to the weld centerline followed a “V”shape.Moreover,large welding residual stress and distortion were found in the interface between blisk and fixtures.The stress concentration was reduced sufficiently in starting and end part ofweldment as the fixtures were removed after welding process,while the removing operation had almost no effects on the welding residual stress in the middle section ofweld bead.

  7. Active generalized predictive control of turbine tip clearance for aero-engines

    Institute of Scientific and Technical Information of China (English)

    Peng Kai; Fan Ding; Yang Fan; Fu Qiang; Li Yong

    2013-01-01

    Active control of turbine blade tip clearance continues to be a concern in design and con-trol of gas turbines. Ever increasing demands for improved efficiency and higher operating temper-atures require more stringent tolerances on turbine tip clearance. In this paper, a turbine tip clearance control apparatus and a model of turbine tip clearance are proposed;an implicit active generalized predictive control (GPC), with auto-regressive (AR) error modification and fuzzy adjustment on control horizon, is presented, as well as a quantitative analysis method of robust per-turbation radius of the system. The active clearance control (ACC) of aero-engine turbine tip clear-ance is evaluated in a lapse-rate take-off transient, along with the comparative and quantitative analysis of the stability and robustness of the active tip clearance control system. The results show that the resultant active tip clearance control system with the improved GPC has favorable steady-state and dynamic performance and benefits of increased efficiency, reduced specific fuel consump-tion, and additional service life.

  8. An Aerodynamic Analysis of a Robustly Redesigned Modern Aero-Engine Fan

    CERN Document Server

    Seshadri, Pranay; Shahpar, Shahrokh

    2016-01-01

    This paper documents results from a recent computational study aimed at de-sensitizing fan stage aerodynamics---in a modern, high bypass ratio aero-engine---to the effects of rear-seal leakage flows. These flows are the result of seal erosion between a rotor and stator disk in an engine, and deterioration over the life of an engine. The density-matching technique for optimization under uncertainty was applied to this problem. This involved RANS and adjoint flow solves of a full fan stage carried out at two different leakage conditions. Here a detailed analysis of the fan stage aerodynamics is carried out to determine why exactly the new design is more insensitive to the effects of leakage flows. Specifically, it is shown that this insensitivity is attributed to three main factors: a slight rearward shift in loading, and thus a reduction in incidence; a reduction in the cross-passage pressure gradient; and a re-acceleration of the flow towards the trailing edge, which prevented any corner separation.

  9. New design of a compact aero-robotic drilling end effector: An experimental analysis

    Directory of Open Access Journals (Sweden)

    Shi Zhenyun

    2016-08-01

    Full Text Available This paper presents the development of a normal adjustment cell (NAC in aero-robotic drilling to improve the quality of vertical drilling, by using an intelligent double-eccentric disk normal adjustment mechanism (2-EDNA, a spherical plain bearing and a floating compress module with sensors. After the surface normal vector is calculated based on the laser sensors’ feedback, the 2-EDNA concept is conceived specifically to address the deviation of the spindle from the surface normal at the drilling point. Following the angle calculation, depending on the actual initial position, two precise eccentric disks (PEDs with an identical eccentric radius are used to rotate with the appropriate angles using two high-resolution DC servomotors. The two PEDs will carry the spindle to coincide with the surface normal, keeping the vertex of the drill bit still to avoid repeated adjustment and position compensation. A series of experiments was conducted on an aeronautical drilling robot platform with a precise NAC. The effect of normal adjustment on bore diameter, drilling force, burr size, drilling heat, and tool wear was analyzed. The results validate that using the NAC in robotic drilling results in greatly improved vertical drilling quality and is attainable in terms of intelligence and accuracy.

  10. New design of a compact aero-robotic drilling end effector:An experimental analysis

    Institute of Scientific and Technical Information of China (English)

    Shi Zhenyun; Yuan Peijiang; Wang Qishen; Chen Dongdong; Wang Tianmiao

    2016-01-01

    This paper presents the development of a normal adjustment cell (NAC) in aero-robotic drilling to improve the quality of vertical drilling, by using an intelligent double-eccentric disk nor-mal adjustment mechanism (2-EDNA), a spherical plain bearing and a floating compress module with sensors. After the surface normal vector is calculated based on the laser sensors’ feedback, the 2-EDNA concept is conceived specifically to address the deviation of the spindle from the sur-face normal at the drilling point. Following the angle calculation, depending on the actual initial position, two precise eccentric disks (PEDs) with an identical eccentric radius are used to rotate with the appropriate angles using two high-resolution DC servomotors. The two PEDs will carry the spindle to coincide with the surface normal, keeping the vertex of the drill bit still to avoid repeated adjustment and position compensation. A series of experiments was conducted on an aeronautical drilling robot platform with a precise NAC. The effect of normal adjustment on bore diameter, dril-ling force, burr size, drilling heat, and tool wear was analyzed. The results validate that using the NAC in robotic drilling results in greatly improved vertical drilling quality and is attainable in terms of intelligence and accuracy.

  11. Propulsion System Dynamic Modeling for the NASA Supersonic Concept Vehicle: AeroPropulsoServoElasticity

    Science.gov (United States)

    Kopasakis, George; Connolly, Joseph; Seidel, Jonathan

    2014-01-01

    A summary of the propulsion system modeling under NASA's High Speed Project (HSP) AeroPropulsoServoElasticity (APSE) task is provided with a focus on the propulsion system for the low-boom supersonic configuration developed by Lockheed Martin and referred to as the N+2 configuration. This summary includes details on the effort to date to develop computational models for the various propulsion system components. The objective of this paper is to summarize the model development effort in this task, while providing more detail in the modeling areas that have not been previously published. The purpose of the propulsion system modeling and the overall APSE effort is to develop an integrated dynamic vehicle model to conduct appropriate unsteady analysis of supersonic vehicle performance. This integrated APSE system model concept includes the propulsion system model, and the vehicle structural-aerodynamics model. The development to date of such a preliminary integrated model will also be summarized in this report.propulsion system dynamics, the structural dynamics, and aerodynamics.

  12. Nonlocal sparse model with adaptive structural clustering for feature extraction of aero-engine bearings

    Science.gov (United States)

    Zhang, Han; Chen, Xuefeng; Du, Zhaohui; Li, Xiang; Yan, Ruqiang

    2016-04-01

    Fault information of aero-engine bearings presents two particular phenomena, i.e., waveform distortion and impulsive feature frequency band dispersion, which leads to a challenging problem for current techniques of bearing fault diagnosis. Moreover, although many progresses of sparse representation theory have been made in feature extraction of fault information, the theory also confronts inevitable performance degradation due to the fact that relatively weak fault information has not sufficiently prominent and sparse representations. Therefore, a novel nonlocal sparse model (coined NLSM) and its algorithm framework has been proposed in this paper, which goes beyond simple sparsity by introducing more intrinsic structures of feature information. This work adequately exploits the underlying prior information that feature information exhibits nonlocal self-similarity through clustering similar signal fragments and stacking them together into groups. Within this framework, the prior information is transformed into a regularization term and a sparse optimization problem, which could be solved through block coordinate descent method (BCD), is formulated. Additionally, the adaptive structural clustering sparse dictionary learning technique, which utilizes k-Nearest-Neighbor (kNN) clustering and principal component analysis (PCA) learning, is adopted to further enable sufficient sparsity of feature information. Moreover, the selection rule of regularization parameter and computational complexity are described in detail. The performance of the proposed framework is evaluated through numerical experiment and its superiority with respect to the state-of-the-art method in the field is demonstrated through the vibration signals of experimental rig of aircraft engine bearings.

  13. Aero-hydro-elastic simulation platform for wave energy systems and floating wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Kallesoee, B.S.

    2011-01-15

    This report present results from the PSO project 2008-1-10092 entitled Aero-Hydro-Elastic Simulation Platform for Wave Energy Systems and floating Wind Turbines that deals with measurements, modelling and simulations of the world's first combined wave and wind energy platform. The floating energy conversion platform, Poseidon, is owned and operated by Floating Power Plant A/S. The platform has been operating for two test periods; one period where it was operating as a wave energy conversion platform only and one period where the three turbines was mounted and the platform operated as a combined wind and wave energy platform. The PSO project has equipped the platform with comprehensive measurements equipment for measuring platform motion, wave and wind conditions and turbine loads. Data from the first test period has been used for determine if the turbine could be mounted on the platform. Preliminary analysis of data from the second test period indicates that the platform is suitable as wind turbine foundation and that the turbines reduce the platform motion. (Author)

  14. Towards an Aero-Propulso-Servo-Elasticity Analysis of a Commercial Supersonic Transport

    Science.gov (United States)

    Connolly, Joseph W.; Kopasakis, George; Chwalowski, Pawel; Sanetrik, Mark D.; Carlson, Jan-Renee; Silva, Walt A.; McNamara, Jack

    2016-01-01

    This paper covers the development of an aero-propulso-servo-elastic (APSE) model using computational fluid dynamics (CFD) and linear structural deformations. The APSE model provides the integration of the following two previously developed nonlinear dynamic simulations: a variable cycle turbofan engine and an elastic supersonic commercial transport vehicle. The primary focus of this study is to provide a means to include relevant dynamics of a turbomachinery propulsion system into the aeroelastic studies conducted during a vehicle design, which have historically neglected propulsion effects. A high fidelity CFD tool is used here for the integration platform. The elastic vehicle neglecting the propulsion system serves as a comparison of traditional approaches to the APSE results. An overview of the methodology is presented for integrating the propulsion system and elastic vehicle. Static aeroelastic analysis comparisons between the traditional and developed APSE models for a wing tip detection indicate that the propulsion system impact on the vehicle elastic response could increase the detection by approximately ten percent.

  15. Analysis and quantification of the diversities of aerosol life cycles within AeroCom

    Directory of Open Access Journals (Sweden)

    C. Textor

    2006-01-01

    Full Text Available Simulation results of global aerosol models have been assembled in the framework of the AeroCom intercomparison exercise. In this paper, we analyze the life cycles of dust, sea salt, sulfate, black carbon and particulate organic matter as simulated by sixteen global aerosol models. The differences among the results (model diversities for sources and sinks, burdens, particle sizes, water uptakes, and spatial dispersals have been established. These diversities have large consequences for the calculated radiative forcing and the aerosol concentrations at the surface. Processes and parameters are identified which deserve further research. The AeroCom all-models-average emissions are dominated by the mass of sea salt (SS, followed by dust (DU, sulfate (SO4, particulate organic matter (POM, and finally black carbon (BC. Interactive parameterizations of the emissions and contrasting particles sizes of SS and DU lead generally to higher diversities of these species, and for total aerosol. The lower diversity of the emissions of the fine aerosols, BC, POM, and SO4, is due to the use of similar emission inventories, and does therefore not necessarily indicate a better understanding of their sources. The diversity of SO4-sources is mainly caused by the disagreement on depositional loss of precursor gases and on chemical production. The diversities of the emissions are passed on to the burdens, but the latter are also strongly affected by the model-specific treatments of transport and aerosol processes. The burdens of dry masses decrease from largest to smallest: DU, SS, SO4, POM, and BC. The all-models-average residence time is shortest for SS with about half a day, followed by SO4 and DU with four days, and POM and BC with six and seven days, respectively. The wet deposition rate is controlled by the solubility and increases from DU, BC, POM to SO4 and SS. It is the dominant sink for SO4, BC, and POM, and contributes about one third to the total removal

  16. Calibration of aero-structural reduced order models using full-field experimental measurements

    Science.gov (United States)

    Perez, R.; Bartram, G.; Beberniss, T.; Wiebe, R.; Spottswood, S. M.

    2017-03-01

    The structural response of hypersonic aircraft panels is a multi-disciplinary problem, where the nonlinear structural dynamics, aerodynamics, and heat transfer models are coupled. A clear understanding of the impact of high-speed flow effects on the structural response, and the potential influence of the structure on the local environment, is needed in order to prevent the design of overly-conservative structures, a common problem in past hypersonic programs. The current work investigates these challenges from a structures perspective. To this end, the first part of this investigation looks at the modeling of the response of a rectangular panel to an external heating source (thermo-structural coupling) where the temperature effect on the structure is obtained from forward looking infrared (FLIR) measurements and the displacement via 3D-digital image correlation (DIC). The second part of the study uses data from a previous series of wind-tunnel experiments, performed to investigate the response of a compliant panel to the effects of high-speed flow, to train a pressure surrogate model. In this case, the panel aero-loading is obtained from fast-response pressure sensitive paint (PSP) measurements, both directly and from the pressure surrogate model. The result of this investigation is the use of full-field experimental measurements to update the structural model and train a computational efficient model of the loading environment. The use of reduced order models, informed by these full-field physical measurements, is a significant step toward the development of accurate simulation models of complex structures that are computationally tractable.

  17. Sensitivity Analysis on Variation of Vane Natural Frequency of a Typical Aero Engine Impeller

    Directory of Open Access Journals (Sweden)

    Selwyn Anbarasan

    2015-08-01

    Full Text Available Centrifugal compressors are widely used in small and medium class turbo shaft and turbo prop aero engines. Inevitably the variation in the manufacturing process will lead to variation in natural frequency of blade vanes in an impeller which usually termed as Mistuning. The variation in natural frequency will increase the forced frequency response of the vanes than the tuned vanes. In-service deterioration of vanes dimension due to erosion, corrosion and FOD also adds to further variation in natural frequency. The amplification factor of the response will lead to reduced HCF life of the vanes than the tuned vanes. It is important for the designer to envisage the variation of natural frequency of the vanes to estimate the life of the impeller to avoid premature failure. This also helps in monitoring the health of the impeller during service. This paper deals with prediction of the effects of manufacturing/geometry variation and variation in material properties on impeller vane natural frequency of a turbo shaft engine. FEM model is created to accommodate the geometry variation of the impeller. The parameters influencing the natural frequency are varied and its corresponding variation in frequency is predicted. Several conditions are also simulated and sensitivity analysis is carried out with the above result to predict the order of influencing parameters. Influencing parameters are ranked and the most influencing parameter is found to be the Young’s Modulus of the material for this case of impeller. Maximum influencing parameter Young’s modulus contributes to 5.8% variation and the least contributing factor density to 0.6% variation in natural frequency. This result enables the designer to forecast the possible range of natural frequencies in the design phase, so that he can limit the analysis to predict the response due to mistuning to the estimated range of frequencies.

  18. Fully Coupled Aero-Thermochemical-Elastic Simulations of an Eroding Graphite Nozzle

    Science.gov (United States)

    Blades, E. L.; Reveles, N. D.; Nucci, M.; Maclean, M.

    2017-01-01

    A multiphysics simulation capability has been developed that incorporates mutual interactions between aerodynamics, structural response from aero/thermal loading, ablation/pyrolysis, heating, and surface-to-surface radiation to perform high-fidelity, fully coupled aerothermoelastic ablation simulations, which to date had been unattainable. The multiphysics framework couples CHAR (a 3-D implicit charring ablator solver), Loci/CHEM (a computational fluid dynamics solver for high-speed chemically reacting flows), and Abaqus (a nonlinear structural dynamics solver) to create a fully coupled aerothermoelastic charring ablative solver. The solvers are tightly coupled in a fully integrated fashion to resolve the effects of the ablation pyrolysis and charring process and chemistry products upon the flow field, the changes in surface geometry due to recession upon the flow field, and thermal-structural analysis of the body from the induced aerodynamic heating from the flow field. The multiphysics framework was successfully demonstrated on a solid rocket motor graphite nozzle erosion application. Comparisons were made with available experimental data that measured the throat erosion during the motor firing. The erosion data is well characterized, as the test rig was equipped with a windowed nozzle section for real-time X-ray radiography diagnostics of the instantaneous throat variations for deducing the instantaneous erosion rates. The nozzle initially undergoes a nozzle contraction due to thermal expansion before ablation effects are able to widen the throat. A series of parameters studies were conducted using the coupled simulation capability to determine the sensitivity of the nozzle erosion to different parameters. The parameter studies included the shape of the nozzle throat (flat versus rounded), the material properties, the effect of the choice of turbulence model, and the inclusion or exclusion of the mechanical thermal expansion. Overall, the predicted results match

  19. Narrow band imaging and high definition television in the endoscopic evaluation of upper aero-digestive tract cancer.

    Science.gov (United States)

    Piazza, C; Cocco, D; Del Bon, F; Mangili, S; Nicolai, P; Peretti, G

    2011-04-01

    Narrow band imaging and high definition television are recent innovations in upper aero-digestive tract endoscopy. Aim of this prospective, non-randomized, unblinded study was to establish the diagnostic advantage of these procedures in the evaluation of squamous cell cancer arising from various upper aero-digestive tract sites. Between April 2007 and January 2010, 444 patients affected by upper aero-digestive tract squamous cell cancer, or previously treated for it, were evaluated by white light and narrow band imaging ± high definition television endoscopy, both in the pre-/intra-operative setting and during follow-up. Tumour resection was performed taking into account narrow band imaging and high definition television information to obtain histopathologic confirmation of their validity. Endoscopic and pathologic data were subsequently matched to obtain sensitivity, specificity, positive, negative predictive values, and accuracy. Overall, 110 (25%) patients showed adjunctive findings by narrow band imaging ± high definition television when compared to standard white light endoscopy. Of these patients, 98 (89%) received histopatological confirmation. The sensitivity, specificity, positive, negative predictive values, and accuracy for white light-high definition television were 41%, 92%, 87%, 82%, and 67%, for narrow band imaging alone 75%, 87%, 87%, 74%, and 80%, and for narrow band imaging-high definition television 97%, 84%, 88%, 96%, and 92%. The highest diagnostic gain was observed in the oral cavity and oropharynx (25%). Narrow band imaging and high definition television were of value in the definition of superficial tumour extension, and in the detection of synchronous lesions in the pre-/intra-operative settings. These technologies also played an important role during post-treatment surveillance for early detection of persistences, recurrences, and metachronous tumours.

  20. Numerical Prediction of Flow and Heat Transfer on lubricant Supplying and Scavenging Flow Path of an Aero-Engine Lubrication System

    Science.gov (United States)

    Huang, S. Q.; Liu, Z. X.; Lv, Y. G.; Zhang, L. F.; Xu, T.

    This paper presents a numerical model of internal flows on lubricant supplying and scavenging flow path of an aero-engine lubrication system. The numerical model was built in the General Analysis Software of Aero-engine Lubrication System (GASLS), developed by Northwestern Polytechnical University. The lubricant flow flux, pressure and temperature distribution at steady state were calculated. GASLS is a general purpose computer program employed a ID steady state network algorithm for analyzing flowrates, pressures and temperatures in a complex flow network. All kinds of aero-engine lubrication systems can be divided into finite correlative typical elements and nodes from which the calculation network is developed in GASLS. Special emphasis is put on how to use combinational elements which is a type of typical elements to replace some complex components such as bearing compartments, accessory drive gearboxes or heat exchangers. This method can reduce network complexity and improve calculation efficiency. The computational results show good agreement with experimental data.

  1. On improving Efficiency and Accuracy of Variable-Fidelity Surrogate Modeling in Aero-data for Loads Context

    DEFF Research Database (Denmark)

    Han, Zhonghua; Zimmermann, Ralf; Goertz, Stefan

    2009-01-01

    ) and a generalized hybrid bridge function, have been developed to improve the efficiency and accuracy of the existing Variable-Fidelity Modeling (VFM) approach. These new algorithms and features are demonstrated and evaluated for analytical functions and used to construct a global surrogate model for the aerodynamic......Variable-fidelity surrogate modeling offers an efficient way to generate aerodynamic data for aero-loads prediction based on a set of CFD methods with varying degree of fidelity and computational expense. In this paper, new algorithms, such as a Gradient-Enhanced Kriging method (direct GEK...

  2. Least Squares Support Vector Machine Based Real-Time Fault Diagnosis Model for Gas Path Parameters of Aero Engines

    Institute of Scientific and Technical Information of China (English)

    WANG Xu-hui; HUANG Sheng-guo; WANG Ye; LIU Yong-jian; SHU Ping

    2009-01-01

    Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines.Firstly,the deviation data of engine cruise are analyzed.Then,model selection is conducted using pattern search method.Finally,by decoding aircraft communication addressing and reporting system (ACARS) report,a real-time cruise data set is acquired,and the diagnosis model is adopted to process data.In contrast to the radial basis function (RBF) neutral network,LS-SVM is more suitable for real-time diagnosis of gas turbine engine.

  3. Small wind turbine performance evaluation using field test data and a coupled aero-electro-mechanical model

    Science.gov (United States)

    Wallace, Brian D.

    A series of field tests and theoretical analyses were performed on various wind turbine rotor designs at two Penn State residential-scale wind-electric facilities. This work involved the prediction and experimental measurement of the electrical and aerodynamic performance of three wind turbines; a 3 kW rated Whisper 175, 2.4 kW rated Skystream 3.7, and the Penn State designed Carolus wind turbine. Both the Skystream and Whisper 175 wind turbines are OEM blades which were originally installed at the facilities. The Carolus rotor is a carbon-fiber composite 2-bladed machine, designed and assembled at Penn State, with the intent of replacing the Whisper 175 rotor at the off-grid system. Rotor aerodynamic performance is modeled using WT_Perf, a National Renewable Energy Laboratory developed Blade Element Momentum theory based performance prediction code. Steady-state power curves are predicted by coupling experimentally determined electrical characteristics with the aerodynamic performance of the rotor simulated with WT_Perf. A dynamometer test stand is used to establish the electromechanical efficiencies of the wind-electric system generator. Through the coupling of WT_Perf and dynamometer test results, an aero-electro-mechanical analysis procedure is developed and provides accurate predictions of wind system performance. The analysis of three different wind turbines gives a comprehensive assessment of the capability of the field test facilities and the accuracy of aero-electro-mechanical analysis procedures. Results from this study show that the Carolus and Whisper 175 rotors are running at higher tip-speed ratios than are optimum for power production. The aero-electro-mechanical analysis predicted the high operating tip-speed ratios of the rotors and was accurate at predicting output power for the systems. It is shown that the wind turbines operate at high tip-speeds because of a miss-match between the aerodynamic drive torque and the operating torque of the wind

  4. Dual-frequency Eddy Current Non-destructive Detection of Fatigue Cracks in Compressor Discs of Aero Engines

    Directory of Open Access Journals (Sweden)

    B. Sasi

    2004-10-01

    Full Text Available Eddy current non-destructive testing is used to inspect the critical aircraft components. The shortcomings of the inspection method identified, based on a few accidents, necessitatethe development of high sensitive and reliable testing procedures for inspecting the critical safety related aircraft components. This paper discusses a dual-frequency eddy current testingprocedure developed for inspection of compressor discs of aero engines for detecting fatigue cracks with high sensitivity and reliability. This procedure is capable of detecting fatigue crackssmaller than 2 mm in comparison to 4 mm cracks that can be detected with the currently practiced eddy current testing procedure.

  5. A method for the assessment of operational severity for a high pressure turbine blade of an aero-engine

    Science.gov (United States)

    Haslam, Anthony; Abu, Abdullahi; Laskaridis, Panagiotis

    2015-12-01

    This paper provides a tool for the estimation of the operational severity of a high pressure turbine blade of an aero engine. A multidisciplinary approach using aircraft/ engine performance models which provide inputs to a thermo-mechanical fatigue damage model is presented. In the analysis, account is taken of blade size, blade metal temperature distribution, relevant heat transfer coefficients and mechanical and thermal stresses. The leading edge of the blade is selected as the critical part in the estimation of damage severity for different design and operational parameters. The study also suggests a method for production of operational severity data for the prediction of maintenance intervals.

  6. Smart rotor modeling aero-servo-elastic modeling of a smart rotor with adaptive trailing edge flaps

    CERN Document Server

    Bergami, Leonardo

    2014-01-01

    A smart rotor is a wind turbine rotor that, through a combination of sensors, control units and actuators actively reduces the variation of the aerodynamic loads it has to withstand. Smart rotors feature?promising load alleviation potential and might provide the technological breakthrough required by the next generation of large wind turbine rotors.The book presents the aero-servo-elastic model of a smart rotor with Adaptive Trailing Edge Flaps for active load alleviation and provides an insight on the rotor aerodynamic, structural and control modeling. A novel model for the unsteady aerodynam

  7. Smoking and the Risk of Upper Aero Digestive Tract Cancers for Men and Women in the Asia-Pacific Region

    Directory of Open Access Journals (Sweden)

    Mark Woodward

    2009-04-01

    Full Text Available Although smoking is an established causal factor for upper aero digestive tract cancer (UADTC, most of the evidence originates from the West. Thus, we analysed data from 455,409 subjects in the Asia Pacific Cohort Studies Collaboration. Over a median of around six years follow-up, 371 deaths from UADTC were observed. The hazard ratio (95% confidence interval for current smokers, compared with those who had never smoked, was 2.36 (1.76 – 3.16, adjusted for age and alcohol drinking. Tobacco control policies are urgently required in Asia to prevent millions of deaths from UADTC that smoking will otherwise cause.

  8. PREFACE: The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014)

    Science.gov (United States)

    Lumban Gaol, Ford; Soewito, Benfano

    2015-01-01

    The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014), was held at Discovery Kartika Plaza Hotel, Kuta, Bali, Indonesia during 11 - 12 October 2014. The AeroEarth 2014 conference aims to bring together researchers and engineers from around the world. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 98 papers and after rigorous review, 17 papers were accepted. The participants come from eight countries. There are four Parallel Sessions and two invited Speakers. It is an honour to present this volume of IOP Conference Series: Earth and Environmental Science (EES) and we deeply thank the authors for their enthusiastic and high-grade contributions. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee

  9. Modeling C-Band Co-Channel Interference From AeroMACS Omni-Directional Antennas to Mobile Satellite Service Feeder Uplinks

    Science.gov (United States)

    Wilson, Jeffrey D.

    2011-01-01

    A new C-band (5091 to 5150 MHz) airport communications system designated as Aeronautical Mobile Airport Communications System (AeroMACS) is being planned under the Federal Aviation Administration s NextGen program. An interference analysis software program, Visualyse Professional (Transfinite Systems Ltd), is being utilized to provide guidelines on limitations for AeroMACS transmitters to avoid interference with other systems. A scenario consisting of a single omni-directional transmitting antenna at each of the major contiguous United States airports is modeled and the steps required to build the model are reported. The results are shown to agree very well with a previous study.

  10. Surface integrity of GH4169 affected by cantilever finish grinding and the application in aero-engine blades

    Directory of Open Access Journals (Sweden)

    Li Xun

    2015-10-01

    Full Text Available GH4169 is the main material for aero-engine blades and integrated blisks. Because GH4169 has a poor milling performance, the profile precision and surface integrity of blades and integrated blisks are difficult to be met by utilizing the conventional milling process, which directly influence the global performance and reliability of aero-engines. Through grinding experiments on parameters and surface integrity optimization, the helical cantilever grinding process utilizing a 300# CBN RB wheel is presented and applied in finish machining of GH4169 blades. The profile errors of the blade surface are within ±0.01 mm, the roughness is less than 0.4 μm, the residual compressive stresses and the hardening rate are appropriate, there are no phenomena of burr and smearing with the grinding chips, and the leading/trailing edge can be smoothly connected with the suction/pressure surface. All the experimental results indicate that this grinding process is greatly suitable for the profile finish machining of GH4169 blades.

  11. Modeled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Science.gov (United States)

    Samset, B. H.; Myhre, G.; Herber, A.; Kondo, Y.; Li, S.-M.; Moteki, N.; Koike, M.; Oshima, N.; Schwarz, J. P.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Berntsen, T. K.; Bian, H.; Chin, M.; Diehl, T.; Easter, R. C.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Lamarque, J.-F.; Lin, G.; Liu, X.; Penner, J. E.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Zhang, K.

    2014-08-01

    Atmospheric black carbon (BC) absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF). However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparision. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modeled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  12. Influence of high rotational speeds on heat transfer and oil film thickness in aero-engine bearing chambers

    Science.gov (United States)

    Wittig, S.; Glahn, A.; Himmelsbach, J.

    1994-04-01

    Increasing the thermal loading of bearing chambers in modern aero-engines requires advanced techniques for the determination of heat transfer characteristics. In the present study, film thickness and heat transfer measurements have been carried out for the complex two-phase oil/air flow in bearing chambers. In order to ensure real engine conditions, a new test facility has been built up, designed for rotational speeds up to n = 16,000 rpm and maximum flow temperatures of T(sub max) = 473 K. Sealing air and lubrication oil flow can be varied nearly in the whole range of aero-engine applications. Special interest is directed toward the development of an ultrasonic oil film thickness measuring technique, which can be used without any reaction on the flow inside the chamber. The determination of local heat transfer at the bearing chamber housing is based on a well-known temperature gradient method using surface temperature measurements and a finite element code to determine temperature distributions within the bearing chamber housing. The influence of high rotational speed on the local heat transfer and the oil film thickness is discussed.

  13. Surface integrity of GH4169 affected by cantilever finish grinding and the application in aero-engine blades

    Institute of Scientific and Technical Information of China (English)

    Li Xun; Ma Shuang; Meng Fanjun

    2015-01-01

    GH4169 is the main material for aero-engine blades and integrated blisks. Because GH4169 has a poor milling performance, the profile precision and surface integrity of blades and integrated blisks are difficult to be met by utilizing the conventional milling process, which directly influence the global performance and reliability of aero-engines. Through grinding experiments on parameters and surface integrity optimization, the helical cantilever grinding process utilizing a 300# CBN RB wheel is presented and applied in finish machining of GH4169 blades. The profile errors of the blade surface are within ±0.01 mm, the roughness is less than 0.4 lm, the residual compressive stresses and the hardening rate are appropriate, there are no phenomena of burr and smearing with the grinding chips, and the leading/trailing edge can be smoothly connected with the suction/pressure surface. All the experimental results indicate that this grinding process is greatly suitable for the profile finish machining of GH4169 blades.

  14. Modelled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Science.gov (United States)

    Samset, B. H.; Myhre, G.; Herber, A.; Kondo, Y.; Li, S.-M.; Moteki, N.; Koike, M.; Oshima, N.; Schwarz, J. P.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Berntsen, T. K.; Bian, H.; Chin, M.; Diehl, T.; Easter, R. C.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Lamarque, J.-F.; Lin, G.; Liu, X.; Penner, J. E.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Zhang, K.

    2014-11-01

    Atmospheric black carbon (BC) absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF). However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long-range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present-day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparison. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modelled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  15. Modeled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Directory of Open Access Journals (Sweden)

    B. H. Samset

    2014-08-01

    Full Text Available Atmospheric black carbon (BC absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF. However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparision. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modeled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  16. Effective L/D: A Theoretical Approach to the Measurement of Aero-Structural Efficiency in Aircraft Design

    Science.gov (United States)

    Guynn, Mark D.

    2015-01-01

    There are many trade-offs in aircraft design that ultimately impact the overall performance and characteristics of the final design. One well recognized and well understood trade-off is that of wing weight and aerodynamic efficiency. Higher aerodynamic efficiency can be obtained by increasing wing span, usually at the expense of higher wing weight. The proper balance of these two competing factors depends on the objectives of the design. For example, aerodynamic efficiency is preeminent for sailplanes and long slender wings result. Although the wing weight-drag trade is universally recognized, aerodynamic efficiency and structural efficiency are not usually considered in combination. This paper discusses the concept of "aero-structural efficiency," which combines weight and drag characteristics. A metric to quantify aero-structural efficiency, termed effective L/D, is then derived and tested with various scenarios. Effective L/D is found to be a practical and robust means to simultaneously characterize aerodynamic and structural efficiency in the context of aircraft design. The primary value of the effective L/D metric is as a means to better communicate the combined system level impacts of drag and structural weight.

  17. Advanced Aero-Propulsive Mid-Lift-to-Drag Ratio Entry Vehicle for Future Exploration Missions

    Science.gov (United States)

    Campbell, C. H.; Stosaric, R. R; Cerimele, C. J.; Wong, K. A.; Valle, G. D.; Garcia, J. A.; Melton, J. E.; Munk, M. M.; Blades, E.; Kuruvila, G.; hide

    2012-01-01

    vehicle stage return, thus making ideas reality. These paradigm shifts include the technology maturation of advanced flexible thermal protection materials onto mid lift-to-drag ratio entry vehicles, the development of integrated supersonic aero-propulsive maneuvering, and the implementation of advanced asymmetric launch shrouds. These paradigms have significant overlap with launch vehicle stage return already being developed by the Air Force and several commercial space efforts. Completing the realization of these combined paradigms holds the key to a high-performing entry vehicle system capability that fully leverages multiple technology benefits to accomplish NASA's Exploration missions to atmospheric planetary destinations.

  18. Ray tracing simulation of aero-optical effect using multiple gradient index layer

    Science.gov (United States)

    Yang, Seul Ki; Seong, Sehyun; Ryu, Dongok; Kim, Sug-Whan; Kwon, Hyeuknam; Jin, Sang-Hun; Jeong, Ho; Kong, Hyun Bae; Lim, Jae Wan; Choi, Jong Hwa

    2016-10-01

    We present a new ray tracing simulation of aero-optical effect through anisotropic inhomogeneous media as supersonic flow field surrounds a projectile. The new method uses multiple gradient-index (GRIN) layers for construction of the anisotropic inhomogeneous media and ray tracing simulation. The cone-shaped projectile studied has 19° semi-vertical angle; a sapphire window is parallel to the cone angle; and an optical system of the projectile was assumed via paraxial optics and infrared image detector. The condition for the steady-state solver conducted through computational fluid dynamics (CFD) included Mach numbers 4 and 6 in speed, 25 km altitude, and 0° angle of attack (AoA). The grid refractive index of the flow field via CFD analysis and Gladstone-Dale relation was discretized into equally spaced layers which are parallel with the projectile's window. Each layer was modeled as a form of 2D polynomial by fitting the refractive index distribution. The light source of ray set generated 3,228 rays for varying line of sight (LOS) from 10° to 40°. Ray tracing simulation adopted the Snell's law in 3D to compute the paths of skew rays in the GRIN layers. The results show that optical path difference (OPD) and boresight error (BSE) decreases exponentially as LOS increases. The variation of refractive index decreases, as the speed of flow field increases the OPD and its rate of decay at Mach number 6 in speed has somewhat larger value than at Mach number 4 in speed. Compared with the ray equation method, at Mach number 4 and 10° LOS, the new method shows good agreement, generated 0.33% of relative root-mean-square (RMS) OPD difference and 0.22% of relative BSE difference. Moreover, the simulation time of the new method was more than 20,000 times faster than the conventional ray equation method. The technical detail of the new method and simulation is presented with results and implication.

  19. 直升机气动噪声研究进展%Progress in aero-acoustic technology of helicopter

    Institute of Scientific and Technical Information of China (English)

    陈平剑; 仲唯贵; 段广战

    2015-01-01

    The status and progress in helicopter aero-acoustic technology is presented,inclu-ding test technology,analysis method and rotor noise control technology.The advanced test technologies such as unsteady pressure measurement,flow field visualization and noise source lo-calization,have been implemented in the acoustic wind tunnel test of rotor noise,which is the es-sential instrument for helicopter aero-acoustic research.Flight test of helicopter aero-acoustic measurements has become a necessary technique in the programs of helicopter noise certification and helicopter noise reduction investigation.With the development of helicopter aero-acoustic noise analysis method,many software tools for rotor noise prediction have been developed and applied in the helicopter design and noise reduction research,based on the solutions of the FW-H equation and Kirchhoff equation.Low noise blade tip is the primary and effective method for heli-copter noise control,and is used widely in helicopter design.Moreover,new technologies such as noise abatement operation and active rotor noise control have been validated by flight test,but have not been used in helicopter design get.Initiated by the demands to design environmentally compatible helicopter,both societies of industry and academia will devote more effort in helicop-ter aero-acoustic technology research.%对直升机气动噪声的研究进展进行了综述,内容包括试验技术、理论分析方法和噪声抑制技术。声学风洞试验是直升机气动噪声研究的基本手段,其中非定常载荷测试、流场显示和声源定位等先进测试技术已实现应用;飞行试验在直升机噪声适航标准完善和噪声控制技术研究等方面已成为必不可少的研究和验证手段。直升机气动噪声的理论体系不断完善,包括声类比法、Kirchhoff/CFD 混合法等旋翼气动噪声分析方法都已形成分析程序,成为直升机研发的有效工具。直升机气动噪声

  20. A multi-scale model for geared transmission aero-thermodynamics

    Science.gov (United States)

    McIntyre, Sean M.

    A multi-scale, multi-physics computational tool for the simulation of high-per- formance gearbox aero-thermodynamics was developed and applied to equilibrium and pathological loss-of-lubrication performance simulation. The physical processes at play in these systems include multiphase compressible ow of the air and lubricant within the gearbox, meshing kinematics and tribology, as well as heat transfer by conduction, and free and forced convection. These physics are coupled across their representative space and time scales in the computational framework developed in this dissertation. These scales span eight orders of magnitude, from the thermal response of the full gearbox O(100 m; 10 2 s), through effects at the tooth passage time scale O(10-2 m; 10-4 s), down to tribological effects on the meshing gear teeth O(10-6 m; 10-6 s). Direct numerical simulation of these coupled physics and scales is intractable. Accordingly, a scale-segregated simulation strategy was developed by partitioning and treating the contributing physical mechanisms as sub-problems, each with associated space and time scales, and appropriate coupling mechanisms. These are: (1) the long time scale thermal response of the system, (2) the multiphase (air, droplets, and film) aerodynamic flow and convective heat transfer within the gearbox, (3) the high-frequency, time-periodic thermal effects of gear tooth heating while in mesh and its subsequent cooling through the rest of rotation, (4) meshing effects including tribology and contact mechanics. The overarching goal of this dissertation was to develop software and analysis procedures for gearbox loss-of-lubrication performance. To accommodate these four physical effects and their coupling, each is treated in the CFD code as a sub problem. These physics modules are coupled algorithmically. Specifically, the high- frequency conduction analysis derives its local heat transfer coefficient and near-wall air temperature boundary conditions from a quasi

  1. Evaluation of the aero-optical properties of the SOFIA cavity by means of computional fluid dynamics and a super fast diagnostic camera

    Science.gov (United States)

    Engfer, Christian; Pfüller, Enrico; Wiedemann, Manuel; Wolf, Jürgen; Lutz, Thorsten; Krämer, Ewald; Röser, Hans-Peter

    2012-09-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5 m reflecting telescope housed in an open cavity on board of a Boeing 747SP. During observations, the cavity is exposed to transonic flow conditions. The oncoming boundary layer evolves into a free shear layer being responsible for optical aberrations and for aerodynamic and aeroacoustic disturbances within the cavity. While the aero-acoustical excitation of an airborne telescope can be minimized by using passive flow control devices, the aero-optical properties of the flow are difficult to improve. Hence it is important to know how much the image seen through the SOFIA telescope is perturbed by so called seeing effects. Prior to the SOFIA science fights Computational Fluid Dynamics (CFD) simulations using URANS and DES methods were carried out to determine the flow field within and above the cavity and hence in the optical path in order to provide an assessment of the aero-optical properties under baseline conditions. In addition and for validation purposes, out of focus images have been taken during flight with a Super Fast Diagnostic Camera (SFDC). Depending on the binning factor and the sub-array size, the SFDC is able to take and to read out images at very high frame rates. The paper explains the numerical approach based on CFD to evaluate the aero-optical properties of SOFIA. The CFD data is then compared to the high speed images taken by the SFDC during flight.

  2. MAINTENANCE LEVEL DECISION OF AERO-ENGINE BASED ON VPRS THEORY%基于VPRS理论的航空发动机送修等级决策

    Institute of Scientific and Technical Information of China (English)

    张海军; 左洪福; 梁剑

    2005-01-01

    An aero-engine is a typically repairable and complex system and its maintenance level has a close relationship with the maintenance cost. The inaccurate measurement for the maintenance level of an aero-engine can induce higher overhaul maintenance costs. Variable precision rough set (VPRS) theory is used to determine the maintenance level of an aero-engine. According to the relationship between condition information and performance parameters of aero-engine modules, decision rules are established for reflecting the real condition of an aeroengine when its maintenance level needs to be determined. Finally, the CF6 engine is used as an example to illustrate the method to be effective.%应用变精度粗糙集理论研究了发动机状态信息与单元体性能参数之间的关系,提出了一种基于信息熵属性约简的航空公司发动机维修等级决策方法,从而在维修决策时能够更加客观地反映发动机实际损伤程度.最后以CF6型发动机维修等级决策规则生成为例说明了该决策方法的有效性.

  3. Development of mathematical models for the aero derivative and heavy duty gas turbines; Desenvolvimento de modelos matematicos para as turbinas a gas aeroderivativas e heavy duty

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Marcelo; Mendes, Pedro Paulo de C.; Ferreira, Claudio; Passaro, Mauricio Campos; Gomes, Leonardo Vinicius [Escola Federal de Engenharia de Itajuba, MG (Brazil). Dept. de Eletronica]. E-mails: freire_marcelo@hotmail.com; ppaulo@iee.efei.br; claudio@iee.efei.br; mcpassaro@uol.com.br; leonardo@iee.efei.br

    2002-07-01

    This paper develops, implements and simulates simplified mathematical models of multiple shafts, aero derivatives and heavy-duty gas turbines, aiming the subsides for studies of power systems dynamic behaviour. These components are fundamental to an approximated evaluation of the National Integrated System after the new thermoelectric plants are incorporated.

  4. APPLICATION OF ROUGH SET THEORY TO MAINTENANCE LEVEL DECISION-MAKING FOR AERO-ENGINE MODULES BASED ON INCREMENTAL KNOWLEDGE LEARNING

    Institute of Scientific and Technical Information of China (English)

    陆晓华; 左洪福; 蔡景

    2013-01-01

    The maintenance of an aero-engine usually includes three levels ,and the maintenance cost and period greatly differ depending on the different maintenance levels .To plan a reasonable maintenance budget program , airlines would like to predict the maintenance level of aero-engine before repairing in terms of performance parame-ters ,which can provide more economic benefits .The maintenance level decision rules are mined using the histori-cal maintenance data of a civil aero-engine based on the rough set theory ,and a variety of possible models of upda-ting rules produced by newly increased maintenance cases added to the historical maintenance case database are in-vestigated by the means of incremental machine learning .The continuously updated rules can provide reasonable guidance suggestions for engineers and decision support for planning a maintenance budget program before repai-ring .The results of an example show that the decision rules become more typical and robust ,and they are more accurate to predict the maintenance level of an aero-engine module as the maintenance data increase ,which illus-trates the feasibility of the represented method .

  5. Saksa sõdurid toetavad Tapa väljaõppekeskuse kabeli ehitust / Eda Post

    Index Scriptorium Estoniae

    Post, Eda, 1983-

    2004-01-01

    Põhja-Saksamaal asuva Budeswehri õhuväe 3. väljaõpperügemendi kaplan Arend Engelkes andis Tapa väljaõppekeskusesse pühakoja ehitamiseks veidi üle 23 000 krooni. Väljaõppekeskus plaanib kabeli ehitust alustada järgmisel aastal, vajalik raha kogutakse annetustena

  6. Uuringu järgi toetavad linlased karmi kätt

    Index Scriptorium Estoniae

    2007-01-01

    Uuringufirma Faktum & Ariko küsitluse järgi toetab 69% tallinlastest müügieeskirjade korduva rikkumise korral ettevõttelt alkoholi müügiloa äravõtmist. Tallinna abilinnapea Jaanus Mutli arvamus. Ilmunud ka: Linnaleht : na russkom jazõke, 24. okt. 2007, lk. 3. Linnaleht : na russkom jazõke art. autor Roman Starapopov

  7. Avanesid Eesti kohalikku arengut toetavad EL tõukefondid / Anne Mishina

    Index Scriptorium Estoniae

    Mishina, Anne

    2004-01-01

    24. juunist jõustusid siseministri määrused, millega sätestatakse tingimused EL tõukefondide kohaliku sotsiaal-majanduslikku arengut toetava meetme 4.6 rakendamiseks. Perioodiks 2004-2006 on meetmest Eestile kavandatud 668 miljonit krooni.

  8. Immunochemical estimations of allergenic activities from outdoor aero-allergens, collected by a high-volume air sampler

    DEFF Research Database (Denmark)

    Jensen, J; Poulsen, L K; Mygind, K;

    1989-01-01

    To quantify airborne allergens in amorphus and morphological particles, a survey with collection of aero-allergens on glass fibre filters by means of a high-volume air-sampler (HIVOL) was conducted. In preliminary laboratory experiments we compared various filter elution techniques......, and the pulverizing elution technique was found to be optimal with regard to yield and convenience. When a surfactant, Tween 20 (0.5% v/v), was added to the elution buffer, a recovery of 80% could be obtained. Allergens in eluates were analysed by means of an IgG-subclass RAST inhibition assay. This immunochemical...... method for quantification of airborne allergens was validated, as a high recovery of timothy grass pollen allergens was eluted from air filters, and eluates were shown specific by RAST inhibition. The amount of immunochemically measured airborne timothy and birch allergens collected by means of the HIVOL...

  9. HAWC2 and BeamDyn: Comparison Between Beam Structural Models for Aero-Servo-Elastic Frameworks: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pavese, Christian; Kim, Taeseong; Wang, Qi; Jonkman, Jason; Sprague, Michael A.

    2016-08-01

    This work presents a comparison of two beam codes for aero-servo-elastic frameworks: a new structural model for the aeroelastic code HAWC2 and a new nonlinear beam model, BeamDyn, for the aeroelastic modularization framework FAST v8. The main goal is to establish the suitability of the two approaches to model the structural behaviour of modern wind turbine blades in operation. Through a series of benchmarking structural cases of increasing complexity, the capability of the two codes to simulate highly nonlinear effects is investigated and analyzed. Results show that even though the geometrically exact beam theory can better model effects such as very large deflections, rotations, and structural couplings, an approach based on a multi-body formulation assembled through linear elements is capable of computing accurate solutions for typical nonlinear beam theory benchmarking cases.

  10. Chatter stability prediction in four-axis milling of aero-engine casings with bull-nose end mill

    Institute of Scientific and Technical Information of China (English)

    Zhou Xu; Zhang Dinghua; Luo Ming; Wu Baohai

    2015-01-01

    An analytical model for chatter stability prediction in bull-nose end milling of aero-engine casings is presented in this paper. And the mechanics and dynamics variations due to the complex cutter and workpiece geometry are considered by analyzing the effects of the lead angle on the milling process. Firstly, the tool-workpiece engagement region is obtained by using a previously developed method and divided into several disk elements along the tool-axis direction. Secondly, a 3D dynamic model for stability limit calculation is developed and simplified into a 1D model in normal direction considering only the dominant mode of the workpiece. Then the cutting force coefficients, the start and exit angles corresponding to each disk element are determined. And the total stability lobe diagram is calculated using an iterative algorithm. Finally, several experimental tests are carried out to validate the feasibility and effectiveness of the proposed prediction approach.

  11. Chatter stability prediction in four-axis milling of aero-engine casings with bull-nose end mill

    Directory of Open Access Journals (Sweden)

    Zhou Xu

    2015-12-01

    Full Text Available An analytical model for chatter stability prediction in bull-nose end milling of aero-engine casings is presented in this paper. And the mechanics and dynamics variations due to the complex cutter and workpiece geometry are considered by analyzing the effects of the lead angle on the milling process. Firstly, the tool-workpiece engagement region is obtained by using a previously developed method and divided into several disk elements along the tool-axis direction. Secondly, a 3D dynamic model for stability limit calculation is developed and simplified into a 1D model in normal direction considering only the dominant mode of the workpiece. Then the cutting force coefficients, the start and exit angles corresponding to each disk element are determined. And the total stability lobe diagram is calculated using an iterative algorithm. Finally, several experimental tests are carried out to validate the feasibility and effectiveness of the proposed prediction approach.

  12. High-Temperature Oxidation Behavior of Two Nickel-Based Superalloys Produced by Metal Injection Molding for Aero Engine Applications

    Science.gov (United States)

    Albert, Benedikt; Völkl, Rainer; Glatzel, Uwe

    2014-09-01

    For different high-temperature applications like aero engines or turbochargers, metal injection molding (MIM) of superalloys is an interesting processing alternative. For operation at high temperatures, oxidation behavior of superalloys produced by MIM needs to match the standard of cast or forged material. The oxidation behavior of nickel-based superalloys Inconel 713 and MAR-M247 in the temperature interval from 1073 K to 1373 K (800 °C to 1100 °C) is investigated and compared to cast material. Weight gain is measured discontinuously at different oxidation temperatures and times. Analysis of oxidized samples is done via SEM and EDX-measurements. MIM samples exhibit homogeneous oxide layers with a thickness up to 4 µm. After processing by MIM, Inconel 713 exhibits lower weight gain and thinner oxide layers than MAR-M247.

  13. HAWC2 and BeamDyn: Comparison Between Beam Structural Models for Aero-Servo-Elastic Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Pavese, Christian; Wang, Qi; Kim, Taeseong; Jonkman, Jason; Sprague, Michael A.

    2016-07-01

    This work presents a comparison of two beam codes for aero-servo-elastic frameworks: a new structural model for the aeroelastic code HAWC2 and a new nonlinear beam model, BeamDyn, for the aeroelastic modularization framework FAST v8. The main goal is to establish the suitability of the two approaches to model the structural behaviour of modern wind turbine blades in operation. Through a series of benchmarking structural cases of increasing complexity, the capability of the two codes to simulate highly nonlinear effects is investigated and analyzed. Results show that even though the geometrically exact beam theory can better model effects such as very large deflections, rotations, and structural couplings, an approach based on a multi-body formulation assembled through linear elements is capable of computing accurate solutions for typical nonlinear beam theory benchmarking cases.

  14. On the aero-elastic design of the DTU 10MW wind turbine blade for the LIFES50+ wind tunnel scale model

    DEFF Research Database (Denmark)

    Bayati, I.; Belloli, M.; Bernini, L.

    2016-01-01

    and for different angles of attack. The aero-elastic design algorithm was set to define the optimal spanwise thickness over chord ratio (t/c), the chord length and the twist to match the first flapwise scaled natural frequency. An aluminium mould for the carbon fibre was CNC manufactured based on B-Splines CAD......This paper illustrates the aero-elastic optimal design, the realization and the verification of the wind tunnel scale model blades for the DTU 10 MW wind turbine model, within LIFES50+ project. The aerodynamic design was focused on the minimization of the difference, in terms of thrust coefficient......, with respect to the full scale reference. From the Selig low Reynolds database airfoils, the SD7032 was chosen for this purpose and a proper constant section wing was tested at DTU red wind tunnel, providing force and distributed pressure coefficients for the design, in the Reynolds range 30-250 E3...

  15. Aerosol single-scattering albedo over the global oceans: Comparing PARASOL retrievals with AERONET, OMI, and AeroCom models estimates

    Energy Technology Data Exchange (ETDEWEB)

    Lacagnina, Carlo [SRON Netherlands Institute for Space Research, Utrecht Netherlands; Hasekamp, Otto P. [SRON Netherlands Institute for Space Research, Utrecht Netherlands; Bian, Huisheng [Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, Catonsville Maryland USA; Curci, Gabriele [Department of Physical and Chemical Sciences, University of L' Aquila, L' Aquila Italy; CETEMPS, University of L' Aquila, L' Aquila Italy; Myhre, Gunnar [Center for International Climate and Environmental Research - Oslo, Oslo Norway; van Noije, Twan [KNMI Royal Netherlands Meteorological Institute, De Bilt Netherlands; Schulz, Michael [Norwegian Meteorological Institute, Oslo Norway; Skeie, Ragnhild B. [Center for International Climate and Environmental Research - Oslo, Oslo Norway; Takemura, Toshihiko [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Zhang, Kai [Pacific Northwest National Laboratory, Richland, Washington USA; Max Planck Institute for Meteorology, Hamburg Germany

    2015-09-27

    The aerosol Single Scattering Albedo (SSA) over the global oceans is evaluated based on polarimetric measurements by the PARASOL satellite. The retrieved values for SSA and Aerosol Optical Depth (AOD) agree well with the ground-based measurements of the AErosol RObotic NETwork (AERONET). The global coverage provided by the PARASOL observations represents a unique opportunity to evaluate SSA and AOD simulated by atmospheric transport model runs, as performed in the AeroCom framework. The SSA estimate provided by the AeroCom models is generally higher than the SSA retrieved from both PARASOL and AERONET. On the other hand, the mean simulated AOD is about right or slightly underestimated compared with observations. An overestimate of the SSA by the models would suggest that these simulate an overly strong aerosol radiative cooling at top-of-atmosphere (TOA) and underestimate it at surface. This implies that aerosols have a potential stronger impact within the atmosphere than currently simulated.

  16. THE APPLICATION OF REMOTE SENSING AND AERO-GEOPHYSICS DATA FUSION ON METALLOGENIC PROGNOSIS IN QIMANTAGE OF EAST KUNLUN MONTAIN AREA

    OpenAIRE

    2013-01-01

    Based on west of Qimantage of East Kunlun mountain area, takes advantage of ASTER data, according to the altered mineral spectral characteristics, remote sensing alteration information is extracted. Incorporation the anomaly extraction results with high-precision aero geophysical data processing results, a multiple resource information fusion model is proposed. The fusion model of two totally different type of data which is a special attention in geospatial academia now, which can im...

  17. Evaluation of the aerosol vertical distribution in global aerosol models through comparison against CALIOP measurements: AeroCom phase II results

    Science.gov (United States)

    Koffi, Brigitte; Schulz, Michael; Bréon, François-Marie; Dentener, Frank; Steensen, Birthe Marie; Griesfeller, Jan; Winker, David; Balkanski, Yves; Bauer, Susanne E.; Bellouin, Nicolas; Berntsen, Terje; Bian, Huisheng; Chin, Mian; Diehl, Thomas; Easter, Richard; Ghan, Steven; Hauglustaine, Didier A.; Iversen, Trond; Kirkevâg, Alf; Liu, Xiaohong; Lohmann, Ulrike; Myhre, Gunnar; Rasch, Phil; Seland, Åyvind; Skeie, Ragnhild B.; Steenrod, Stephen D.; Stier, Philip; Tackett, Jason; Takemura, Toshihiko; Tsigaridis, Kostas; Vuolo, Maria Raffaella; Yoon, Jinho; Zhang, Kai

    2016-06-01

    The ability of 11 models in simulating the aerosol vertical distribution from regional to global scales, as part of the second phase of the AeroCom model intercomparison initiative (AeroCom II), is assessed and compared to results of the first phase. The evaluation is performed using a global monthly gridded data set of aerosol extinction profiles built for this purpose from the CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) Layer Product 3.01. Results over 12 subcontinental regions show that five models improved, whereas three degraded in reproducing the interregional variability in Zα0-6 km, the mean extinction height diagnostic, as computed from the CALIOP aerosol profiles over the 0-6 km altitude range for each studied region and season. While the models' performance remains highly variable, the simulation of the timing of the Zα0-6 km peak season has also improved for all but two models from AeroCom Phase I to Phase II. The biases in Zα0-6 km are smaller in all regions except Central Atlantic, East Asia, and North and South Africa. Most of the models now underestimate Zα0-6 km over land, notably in the dust and biomass burning regions in Asia and Africa. At global scale, the AeroCom II models better reproduce the Zα0-6 km latitudinal variability over ocean than over land. Hypotheses for the performance and evolution of the individual models and for the intermodel diversity are discussed. We also provide an analysis of the CALIOP limitations and uncertainties contributing to the differences between the simulations and observations.

  18. Simulating Global AeroMACS Airport Ground Station Antenna Power Transmission Limits to Avoid Interference With Mobile Satellite Service Feeder Uplinks

    Science.gov (United States)

    Wilson, Jeffrey D.

    2013-01-01

    The Aeronautical Mobile Airport Communications System (AeroMACS), which is based upon the IEEE 802.16e mobile wireless standard, is expected to be implemented in the 5091 to 5150 MHz frequency band. As this band is also occupied by Mobile Satellite Service feeder uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference are under analysis in order to enable the definition of standards that assure that such interference will be avoided. In this study, the cumulative interference power distribution at low Earth orbit from transmitters at global airports was simulated with the Visualyse Professional software. The dependence of the interference power on antenna distribution, gain patterns, duty cycle, and antenna tilt was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power from global airports required to maintain the cumulative interference power under the established threshold.

  19. Research on the aero-thermal effects by 3D analysis model of the optical window of the infrared imaging guidance

    Science.gov (United States)

    Xu, Bo; Li, Lin; Zhu, Ying

    2014-11-01

    Researches on hypersonic vehicles have been a hotspot in the field of aerospace because of the pursuits for higher speed by human being. Infrared imaging guidance is playing a very important role in modern warfare. When an Infrared Ray(IR) imaging guided missile is flying in the air at high speed, its optical dome suffers from serious aero-optic effects because of air flow. The turbulence around the dome and the thermal effects of the optical window would cause disturbance to the wavefront from the target. Therefore, detected images will be biased, dithered and blurred, and the capabilities of the seeker for detecting, tracking and recognizing are weakened. In this paper, methods for thermal and structural analysis with Heat Transfer and Elastic Mechanics are introduced. By studying the aero-thermal effects and aero-thermal radiation effects of the optical window, a 3D analysis model of the optical window is established by using finite element method. The direct coupling analysis is employed as a solving strategy. The variation regularity of the temperature field is obtained. For light with different incident angles, the influence on the ray propagation caused by window deformation is analyzed with theoretical calculation and optical/thermal/structural integrated analysis method respectively.

  20. A Honeycomb-Structured Ti-6Al-4V Oil-Gas Separation Rotor Additively Manufactured by Selective Electron Beam Melting for Aero-engine Applications

    Science.gov (United States)

    Tang, H. P.; Wang, Q. B.; Yang, G. Y.; Gu, J.; Liu, N.; Jia, L.; Qian, M.

    2016-03-01

    Oil -gas separation is a key process in an aero-engine lubrication system. This study reports an innovative development in oil -gas separation. A honeycomb-structured rotor with hexagonal cone-shaped pore channels has been designed, additively manufactured from Ti-6Al-4V using selective electron beam melting (SEBM) and assessed for oil -gas separation for aero-engine application. The Ti-6Al-4V honeycomb structure showed a high compressive strength of 110 MPa compared to less than 20 MPa for metal foam structures. The oil -gas separation efficiency of the honeycomb-structured separation rotor achieved 99.8% at the rotation speed of 6000 rpm with much lower ventilation resistance (17.3 kPa) than that of the separator rotor constructed using a Ni-Cr alloy foam structure (23.5 kPa). The honeycomb-structured Ti-6Al-4V separator rotor produced by SEBM provides a promising solution to more efficient oil -gas separation in the aero-engine lubrication system.

  1. Comparison of aerosol optical properties above clouds between POLDER and AeroCom models over the South East Atlantic Ocean during the fire season: POLDER/AeroCom Comparison Above Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Peers, F. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Now at College of Engineering, Mathematics, and Physical Sciences, University of Exeter, Exeter UK; Bellouin, N. [Department of Meteorology, University of Reading, Reading UK; Waquet, F. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Ducos, F. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Goloub, P. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Mollard, J. [Department of Meteorology, University of Reading, Reading UK; Myhre, G. [Center for International Climate and Environmental Research - Oslo, Oslo Norway; Skeie, R. B. [Center for International Climate and Environmental Research - Oslo, Oslo Norway; Takemura, T. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Tanré, D. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Thieuleux, F. [Laboratoire d' Optique Atmosphérique, Université Lille 1, Villeneuve d' Ascq France; Zhang, K. [Max Planck Institute for Meteorology, Hamburg Germany; Pacific Northwest National Laboratory, Richland Washington USA

    2016-04-21

    Aerosol properties above clouds have been retrieved over the South East Atlantic Ocean during the fire season 2006 using satellite observations from POLDER (Polarization and Directionality of Earth Reflectances). From June to October, POLDER has observed a mean Above-Cloud Aerosol Optical Thickness (ACAOT) of 0.28 and a mean Above-Clouds Single Scattering Albedo (ACSSA) of 0.87 at 550nm. These results have been used to evaluate the simulation of aerosols above clouds in 5 AeroCom (Aerosol Comparisons between Observations and Models) models (GOCART, HadGEM3, ECHAM5-HAM2, OsloCTM2 and SPRINTARS). Most models do not reproduce the observed large aerosol load episodes. The comparison highlights the importance of the injection height and the vertical transport parameterizations to simulate the large ACAOT observed by POLDER. Furthermore, some models overestimate the ACSSA. In accordance with recent recommendations of the black carbon refractive index, a higher prescription of the imaginary part allows a better comparison with POLDER’s ACSSA.

  2. The effect of harmonized emissions on aerosol properties in global models – an AeroCom experiment

    Directory of Open Access Journals (Sweden)

    C. Textor

    2007-08-01

    Full Text Available The effects of unified aerosol sources on global aerosol fields simulated by different models are examined in this paper. We compare results from two AeroCom experiments, one with different (ExpA and one with unified emissions, injection heights, and particle sizes at the source (ExpB. Surprisingly, harmonization of aerosol sources has only a small impact on the simulated inter-model diversity of the global aerosol burden, and consequently global optical properties, as the results are largely controlled by model-specific transport, removal, chemistry (leading to the formation of secondary aerosols and parameterizations of aerosol microphysics (e.g., the split between deposition pathways and to a lesser extent by the spatial and temporal distributions of the (precursor emissions.

    The burdens of black carbon and especially sea salt become more coherent in ExpB only, because the large ExpA diversities for these two species were caused by a few outliers. The experiment also showed that despite prescribing emission fluxes and size distributions, ambiguities in the implementation in individual models can lead to substantial differences.

    These results indicate the need for a better understanding of aerosol life cycles at process level (including spatial dispersal and interaction with meteorological parameters in order to obtain more reliable results from global aerosol simulations. This is particularly important as such model results are used to assess the consequences of specific air pollution abatement strategies.

  3. USAF bioenvironmental noise data handbook. Volume 172: Hush-noise suppressor (Aero Systems Engineering, Incorporated) far-field noise

    Science.gov (United States)

    Lee, R. A.; Rau, T. H.; Jones, C.

    1982-07-01

    The hush-house noise suppressor was made by Aero Systems Engineering of Texas, Inc. for acoustical suppression of various AF fighter/trainer aircraft during ground runup operations. This report provides measured and extrapolated data defining the bioacoustic environments produced by several aircraft/engines operating in the hush-house suppressor for various engine power configurations. Far-field data measured at 20 locations are normalized to standard meteorological conditions and extrapolated from 75-8000 meters to derive sets of equal-value contours for seven acoustic measures as function of angle and distance from the source. Refer to Volume 1 of this handbook, 'USAF Bioenvironmental Noise Data Handbook, Vol 1: Organization, Content and Application,' AMRL-TR-75(1) 1975, for discussion of the objective and design of the handbook, the types of data presented, measurement procedures, instrumentation, data processing, definitions of quantities, symbols, equations, applications, limitations, etc. Data are presented for the following aircraft/engines operating in the hush-house noise suppressor: F-4, F-15, F-16, F-105, F-106, F-111F and T-38 aircraft and the TF41-A-1, J79-GE-15, F100-PW-100, J75-P19, J-75-P-17 and TF30-P-100 engines.

  4. Physical model of granule adhesion to the belt-electrodes of a tribo-aero-electrostatic separator

    Science.gov (United States)

    Li, Jia; Dascalescu, Lucian; Miloudi, Mohamed; Bilici, Mihai; Xu, Zhenming

    2013-03-01

    Recent studies have demonstrated the effectiveness of tribo-aero-electrostatic separation technologies, which consist in the selective sorting of mixed granular insulating materials in a fluidized bed affected by an electric field orthogonally oriented to the direction of the fluidization air. The aim of the present paper is to put the theoretical bases for the optimization of this process, i. e. maximize the total mass of the granules collected at the two electrodes that generate the electric field. The various forces that drive a granule of given mass and electric charge through the electric field and make it stick to an electrode are expressed as functions of the several input variables and parameters of the process, such as the applied high-voltage or the surface roughness, the size and the position of the electrodes. The concepts of "critical electrostatic field" and "virtual climbing distance" are introduced. The prediction of the theoretical model are confirmed by the results of three sets of experiments, carried out on samples of a granular mixture consisting of 50% Acrylonitrile Butadiene Styrene (ABS) and 50% High Impact Polystyrene (HIPS), originating from the recycling of waste electric and electronic equipment. Higher separation efficiency was obtained when the electric field in the active zone was intensified by the use of an additional electrode connected to the ground and when the collecting electrodes were covered by a thin insulating layer.

  5. 3D modelling of an aero-gravity and -magnetic survey as an first exploration step in a frontier basin

    Science.gov (United States)

    Köther, Nils; Eckard, Marcel; Götze, Hans-Jürgen

    2010-05-01

    The West African Taoudeni basin covers a desert area of about 1.8 million km² and is one of the last frontier basins worldwide. Here Wintershall Holding AG holds acreage of about 68000 km². During 2005-2007 geological surveys and an aero-gravity and -magnetic survey were conducted in this area. The potential field modelling should contribute first insight about the subsurface to plan an economic seismic survey. 2D models lead to poor results. 2008 the results of an internship (NK) were 3D subsurface models, which were enhanced during the following diploma thesis (Köther, 2009). Complex igneous rocks and sparsely distributed constraints lead to an ambiguous interpretation. Therefore, several simple 3D models were compiled with the in-house software IGMAS+, which base on geological ideas of the underground and fit well the measured data. These basic models allow a geophysical evaluation of different geological theories about the subsurface. Also, for a thorough interpretation field transformations (Euler, Curvature, and Derivatives) were calculated. These results led to new constraints for further interpretation of the basin structures and therefore they are important contributions for future exploration e.g. the planning of seismic surveys.

  6. Self-sustained aero-acoustic pulsations in gas transport systems: Experimental study of the influence of closed side branches

    Science.gov (United States)

    Bruggeman, J. C.; Hirschberg, A.; van Dongen, M. E. H.; Wijnands, A. P. J.; Gorter, J.

    1991-11-01

    A theoretical model is proposed for the aero-acoustic sources responsible for low-frequency self-sustained pulsations in pipes with closed side branches. The theory successfully explains the acoustic and hydrodynamic conditions for resonance in experiments with a single side branch. It also predicts the order of magnitude of the pulsation amplitude and the effect of losses due to friction and radiation. A high pulsation level, with acoustic velocities of the order of magnitude of the main flow, is observed in a double side branch set-up when the edges at the junctions are rounded. When in the double side branch set-up the rounded upstream edge of the second T-joint is replaced by a sharp edge, the pulsation amplitude is reduced by a factor of five. This effect, which can be explained with the theory of vortex sound, leads us to the design of spoilers. Various "spoilers" have been tested in scale model and full scale experiments. Some of these reduce the pulsation level by 40 dB.

  7. Concurrent identification of aero-acoustic scattering and noise sources at a flow duct singularity in low Mach number flow

    Science.gov (United States)

    Sovardi, Carlo; Jaensch, Stefan; Polifke, Wolfgang

    2016-09-01

    A numerical method to concurrently characterize both aeroacoustic scattering and noise sources at a duct singularity is presented. This approach combines Large Eddy Simulation (LES) with techniques of System Identification (SI): In a first step, a highly resolved LES with external broadband acoustic excitation is carried out. Subsequently, time series data extracted from the LES are post-processed by means of SI to model both acoustic propagation and noise generation. The present work studies the aero-acoustic characteristics of an orifice placed in a duct at low flow Mach numbers with the "LES-SI" method. Parametric SI based on the Box-Jenkins mathematical structure is employed, with a prediction error approach that utilizes correlation analysis of the output residuals to avoid overfitting. Uncertainties of model parameters due to the finite length of times series are quantified in terms of confidence intervals. Numerical results for acoustic scattering matrices and power spectral densities of broad-band noise are validated against experimental measurements over a wide range of frequencies below the cut-off frequency of the duct.

  8. Nonlinear and chaotic vibration and stability analysis of an aero-elastic piezoelectric FG plate under parametric and primary excitations

    Science.gov (United States)

    Rezaee, Mousa; Jahangiri, Reza

    2015-05-01

    In this study, in the presence of supersonic aerodynamic loading, the nonlinear and chaotic vibrations and stability of a simply supported Functionally Graded Piezoelectric (FGP) rectangular plate with bonded piezoelectric layer have been investigated. It is assumed that the plate is simultaneously exposed to the effects of harmonic uniaxial in-plane force and transverse piezoelectric excitations and aerodynamic loading. It is considered that the potential distribution varies linearly through the piezoelectric layer thickness, and the aerodynamic load is modeled by the first order piston theory. The von-Karman nonlinear strain-displacement relations are used to consider the geometrical nonlinearity. Based on the Classical Plate Theory (CPT) and applying the Hamilton's principle, the nonlinear coupled partial differential equations of motion are derived. The Galerkin's procedure is used to reduce the equations of motion to nonlinear ordinary differential Mathieu equations. The validity of the formulation for analyzing the Limit Cycle Oscillation (LCO), aero-elastic stability boundaries is accomplished by comparing the results with those of the literature, and the convergence study of the FGP plate is performed. By applying the Multiple Scales Method, the case of 1:2 internal resonance and primary parametric resonance are taken into account and the corresponding averaged equations are derived and analyzed numerically. The results are provided to investigate the effects of the forcing/piezoelectric detuning parameter, amplitude of forcing/piezoelectric excitation and dynamic pressure, on the nonlinear dynamics and chaotic behavior of the FGP plate. It is revealed that under the certain conditions, due to the existence of bi-stable region of non-trivial solutions, system shows the hysteretic behavior. Moreover, in absence of airflow, it is observed that variation of control parameters leads to the multi periodic and chaotic motions.

  9. Aero-thermo-dynamic analysis of a low ballistic coefficient deployable capsule in Earth re-entry

    Science.gov (United States)

    Zuppardi, G.; Savino, R.; Mongelluzzo, G.

    2016-10-01

    The paper deals with a microsatellite and the related deployable recovery capsule. The aero-brake is folded at launch and deployed in space and is able to perform a de-orbiting controlled re-entry. This kind of capsule, with a flexible, high temperature resistant fabric, thanks to its lightness and modulating capability, can be an alternative to the current "conventional" recovery capsules. The present authors already analyzed the trajectory and the aerodynamic behavior of low ballistic coefficient capsules during Earth re-entry and Mars entry. In previous studies, aerodynamic longitudinal stability analysis and evaluation of thermal and aerodynamic loads for a possible suborbital re-entry demonstrator were carried out in both continuum and rarefied regimes. The present study is aimed at providing preliminary information about thermal and aerodynamic loads and longitudinal stability for a similar deployable capsule, as well as information about the electronic composition of the plasma sheet and its possible influence on radio communications at the altitudes where GPS black-out could occur. Since the computer tests were carried out at high altitudes, therefore in rarefied flow fields, use of Direct Simulation Monte Carlo codes was mandatory. The computations involved both global aerodynamic quantities (drag and longitudinal moment coefficients) and local aerodynamic quantities (heat flux and pressure distributions along the capsule surface). The results verified that the capsule at high altitude (150 km) is self-stabilizing; it is stable around the nominal attitude or at zero angle of attack and unstable around the reverse attitude or at 180° angle of attack. The analysis also pointed out the presence of extra statically stable equilibrium trim points.

  10. Polymorphisms of peroxisome proliferator-activated receptors and survival of lung cancer and upper aero-digestive tract cancers.

    Science.gov (United States)

    Yang, Ying; Burke, Rita V; Jeon, Christie Y; Chang, Shen-Chih; Chang, Po-Yin; Morgenstern, Hal; Tashkin, Donald P; Mao, Jenny; Cozen, Wendy; Mack, Thomas M; Rao, Jianyu; Zhang, Zuo-Feng

    2014-09-01

    Peroxisome proliferator-activated receptors (PPARs) are transcriptional factors involved in several biological processes such as inflammation, cancer growth, progression and apoptosis that are important in lung and upper aero-digestive tract (UADT) cancer outcomes. Nonetheless, there are no published studies of the relationship between PPARs gene polymorphisms and survival of patients with lung cancer or UADT cancers. 1212 cancer patients (611 lung, 303 oral, 100 pharyngeal, 90 laryngeal, and 108 esophageal) were followed for a median duration of 11 years. We genotyped three potentially functional single nucleotide polymorphisms (SNPs) using Taqman - rs3734254 of the gene PPARD and rs10865710 and rs1801282 of the gene PPARG - and investigated their associations with lung and UADT cancer survival using Cox regression. A semi-Bayesian shrinkage approach was used to reduce the potential for false positive findings when examining multiple associations. The variant homozygote CC (vs. TT) of PPARD rs3734254 was inversely associated with mortality of both lung cancer (adjusted hazard ratio [aHR]=0.63, 95% confidence interval [CI]=0.42, 0.96) and UADT cancers (aHR=0.51, 95% CI=0.27, 0.99). Use of the semi-Bayesian shrinkage approach yielded a posterior aHR for lung cancer of 0.66 (95% posterior limits=0.44, 0.98) and a posterior aHR for UADT cancers of 0.58 (95% posterior limits=0.33, 1.03). Our findings suggest that lung-cancer patients with the CC variant of PPARD rs3734254 may have a survival advantage over lung-cancer patients with other gene variants. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Evaluation of the aerosol vertical distribution in global aerosol models through comparison against CALIOP measurements: AeroCom phase II results: AEROSOL PROFILES IN AEROCOM II GCM

    Energy Technology Data Exchange (ETDEWEB)

    Koffi, Brigitte [European Commission, Joint Research Centre, Institute for Environment and Sustainability, Ispra Italy; Schulz, Michael [Norwegian Meteorological Institute, Oslo Norway; Bréon, François-Marie [Laboratoire des Sciences du Climat et de l' Environnement, Gif-sur-Yvette France; Dentener, Frank [European Commission, Joint Research Centre, Institute for Environment and Sustainability, Ispra Italy; Steensen, Birthe Marie [Norwegian Meteorological Institute, Oslo Norway; Griesfeller, Jan [Norwegian Meteorological Institute, Oslo Norway; Winker, David [NASA Langley Research Center, MS/475, Hampton Virginia USA; Balkanski, Yves [Laboratoire des Sciences du Climat et de l' Environnement, Gif-sur-Yvette France; Bauer, Susanne E. [Center for Climate Systems Research, Columbia University, New York New York USA; NASA Goddard Institute for Space Studies, New York New York USA; Bellouin, Nicolas [Department of Meteorology, University of Reading, Reading UK; Berntsen, Terje [Department of Geosciences, University of Oslo, Oslo Norway; Center for International Climate and Environmental Research-Oslo (CICERO), Oslo Norway; Bian, Huisheng [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore Country Maryland USA; Chin, Mian [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Diehl, Thomas [European Commission, Joint Research Centre, Institute for Environment and Sustainability, Ispra Italy; Easter, Richard [Pacific Northwest National Laboratory, Richland Washington USA; Ghan, Steven [Pacific Northwest National Laboratory, Richland Washington USA; Hauglustaine, Didier A. [Laboratoire des Sciences du Climat et de l' Environnement, Gif-sur-Yvette France; Iversen, Trond [Norwegian Meteorological Institute, Oslo Norway; Department of Geosciences, University of Oslo, Oslo Norway; Kirkevåg, Alf [Norwegian Meteorological Institute, Oslo Norway; Liu, Xiaohong [Pacific Northwest National Laboratory, Richland Washington USA; Now at University of Wyoming, Laramie Wyoming USA; Lohmann, Ulrike [ETH-Zentrum, Zürich Switzerland; Myhre, Gunnar [Center for International Climate and Environmental Research-Oslo (CICERO), Oslo Norway; Rasch, Phil [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Seland, Øyvind [Norwegian Meteorological Institute, Oslo Norway; Skeie, Ragnhild B. [Center for International Climate and Environmental Research-Oslo (CICERO), Oslo Norway; Steenrod, Stephen D. [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Stier, Philip [Department of Physics, University of Oxford, Oxford UK; Tackett, Jason [Science Systems and Applications, Inc., Hampton Virginia USA; Takemura, Toshihiko [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Tsigaridis, Kostas [Center for Climate Systems Research, Columbia University, New York New York USA; NASA Goddard Institute for Space Studies, New York New York USA; Vuolo, Maria Raffaella [Laboratoire des Sciences du Climat et de l' Environnement, Gif-sur-Yvette France; Now at National Institute for Agronomic Research, Thiverval-Grignon France; Yoon, Jinho [Pacific Northwest National Laboratory, Richland Washington USA; Now at Gwangju Institute of Science and Technology, Gwangju Korea; Zhang, Kai [Pacific Northwest National Laboratory, Richland Washington USA; Max Planck Institute for Meteorology, Hamburg Germany

    2016-06-27

    The ability of eleven models in simulating the aerosol vertical distribution from regional to global scales, as part of the second phase of the AeroCom model inter-comparison initiative (AeroCom II) is assessed and compared to results of the first phase. The evaluation is performed using a global monthly gridded dataset of aerosol extinction profiles built on purpose from the CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) Layer Product 3.01. Results over 12 sub-continental regions show that five models improved whereas three degraded in reproducing the Zα 0-6 km mean extinction height diagnostic, which is computed over the 0-6 km altitude range for each studied region and season. While the models’ performance remains highly variable, it has generally improved in terms of inter-regional diversity and seasonality. The biases in Zα 0-6 km have notably decreased in the U.S. and European industrial and downwind maritime regions, whereas the timing of the Zα 0-6 km peak season has improved for all but two models. However, most of the models now show a Zα 0-6 km underestimation over land, notably in the dust and biomass burning regions in Asia and Africa. At global scale, the AeroCom II models better reproduce the Zα 0-6 km latitudinal variability over ocean than over land. Hypotheses for the (changes in the) the performance of the individual models and for the inter-model diversity are discussed. We also provide an analysis of the CALIOP limitations and uncertainties that can contribute to the differences between the simulations and observations.

  12. 间冷回热循环发动机电子样机设计%Digital mock- up design of the intercooled recuperated cycle aero- engine

    Institute of Scientific and Technical Information of China (English)

    曾庆万; 冯松涛; 马健

    2016-01-01

    Based on the tracking and analysis of the application of intercooled recuperated technology on aero-engine overseas, according to the domestic research status, experiment research of intercooler and re⁃cuperator was carried out. The general structure of the intercooled recuperated aero-engine was primarily studied and built as digital mock-up. The layout rules of components, systems, and special intercooler pipe⁃line and recuperator pipeline were summarized. By building the mock-up, the characteristics of project de⁃sign for the intercooled recuperated aero-engine were grasped, and the layout of components and systems were explored, which provide a basement for the optimization of engineering design.%在追踪和分析国外间冷回热技术在航空发动机领域应用的基础上,根据国内研究现状,对间冷器和回热器进行了模拟实验研究。初步拟定了间冷回热发动机总体结构方案,并将此结构方案建立为电子样机。总结了间冷回热发动机中各部件、系统,以及特有的间冷器管路系统和回热器管路系统的布局规律。通过样机建模,初步掌握了间冷回热发动机总体结构方案设计特点,探索了各部件、系统的布局,为间冷回热发动机的进一步研究积累了经验。

  13. Two-Phase Air/Oil Flow in Aero-Engine Bearing Chambers – Assessment of an Analytical Prediction Method for the Internal Wall Heat Transfer

    Directory of Open Access Journals (Sweden)

    A. Glahn

    1999-01-01

    Full Text Available The present paper gives a theoretical outline on liquid film flows driven by superimposed effects of interfacial shear and gravity forces and discusses related heat transfer processes which are relevant for lubrication oil systems of aero engines. It is shown that a simple analytical approach is able to predict measured heat transfer data fairly well. Therefore, it offers scope for improvements within the analysis of bearing chamber heat transfer characteristics as well as for appropriate studies with respect to other components of the lubrication oil system such as vent pipeline elements.

  14. On the aero-elastic design of the DTU 10MW wind turbine blade for the LIFES50+ wind tunnel scale model

    Science.gov (United States)

    Bayati, I.; Belloli, M.; Bernini, L.; Mikkelsen, R.; Zasso, A.

    2016-09-01

    This paper illustrates the aero-elastic optimal design, the realization and the verification of the wind tunnel scale model blades for the DTU 10 MW wind turbine model, within LIFES50+ project. The aerodynamic design was focused on the minimization of the difference, in terms of thrust coefficient, with respect to the full scale reference. From the Selig low Reynolds database airfoils, the SD7032 was chosen for this purpose and a proper constant section wing was tested at DTU red wind tunnel, providing force and distributed pressure coefficients for the design, in the Reynolds range 30-250 E3 and for different angles of attack. The aero-elastic design algorithm was set to define the optimal spanwise thickness over chord ratio (t/c), the chord length and the twist to match the first flapwise scaled natural frequency. An aluminium mould for the carbon fibre was CNC manufactured based on B-Splines CAD definition of the external geometry. Then the wind tunnel tests at Politecnico di Milano confirmed successful design and manufacturing approaches.

  15. The effect of lactose, NaCl and an aero/anaerobic environment on the tyrosine decarboxylase activity of Lactococcus lactis subsp. cremoris and Lactococcus lactis subsp. lactis.

    Science.gov (United States)

    Buňková, Leona; Buňka, František; Pollaková, Eva; Podešvová, Tereza; Dráb, Vladimír

    2011-05-27

    The aim of this work was to study, under model conditions, combined effects of the concentration of lactose (0-1% w/v), NaCl (0-2% w/v) and aero/anaerobiosis on the growth and tyramine production in 3 strains of Lactococcus lactis subsp. lactis and 2 strains of L. lactis subsp. cremoris. The levels of the factors tested were chosen with respect to the conditions which can occur during the real process of natural cheese production, including the culture temperature (10 ± 1°C). In all strains tested, tyrosine decarboxylation was most influenced by NaCl concentration; the highest production of tyramine was obtained within the culture with the highest (2% w/v) salt concentration applied. Two of the strains L. lactis subsp. lactis produced tyramine only in broth with the highest NaCl concentration tested. In the remaining 3 strains of L. lactis, tyramine was detected under all conditions applied. The tested concentration of lactose and aero/anaerobiosis had a less significant effect on tyramine decarboxylation. However, it was also found that at the same concentrations of NaCl and lactose, a higher amount of tyramine was detected under anaerobic conditions. In all strains tested, tyramine decarboxylation started during the active growth phase of the cells.

  16. Study of Selective Gold Plating on Aero Electrical Connector Contacts%航空电连接器接触体局部镀金工艺研究

    Institute of Scientific and Technical Information of China (English)

    孙淼; 徐加有

    2015-01-01

    针对航空电连接器接触件电镀金成本高问题,研究高速局部镀金工艺。主要研究了不同金离子浓度、添加剂浓度和电源的选择对电流密度范围、沉积速率和镀层质量的影响。试验结果表明,采用局部镀金可以满足航空电连接器的产品性能,同时可以节约成本1/3~1/2。%Gold plating on aero electrical con-nector contacts is costly.In order to solve the problem, the selective gold plating is studied. The research of Au+con-centration, additive concentration and choice of power on current density range, deposition rate and coating quality are carried out. Results show that selective gold plating on aero electrical connector contacts can meet product perfor-mance requirements and save 1/3~1/2 of cost.

  17. The effects of plantar flexor static stretching and dynamic stretching using an aero-step on foot pressure during gait in healthy adults: a preliminary study.

    Science.gov (United States)

    Shim, Je-Myung; Jung, Ju-Hyeon; Kim, Hwan-Hee

    2015-07-01

    [Purpose] The aim of this study was to examine whether plantar flexor static stretching and dynamic stretching using an Aero-Step results in changes in foot pressure during gait in healthy adults. [Subjects] Eighteen normal adults were randomly allocated to either a dynamic stretching using an Aero-Step group (DSUAS) group (n = 8) or a static stretching (SS) group (n = 10). [Methods] The DSUAS and SS participants took part in an exercise program for 15 minutes. Outcome measures were foot plantar pressure, which was measured during the subject's gait stance phase; the asymmetric ratio of foot pressure for both feet; and the visual analogue scale (VAS) measured during the interventions. [Results] There were significant differences in the asymmetric ratio of foot pressure for both feet and VAS between the two groups after intervention. However, there were no significant differences in foot plantar pressure during the gait stance phase within both groups. [Conclusion] DSUSAS is an effective stretching method, as pain during it is lower than that with SS, which can minimize the asymmetric ratio of foot pressure for both feet during gait due to asymmetric postural alignment.

  18. Aero-gravity Assisted Manoeuvers within Preliminary Interplanetary Mission Design: a Multi-objective Evolutive Algorithm Approach

    Science.gov (United States)

    Povoleri, A.; Lavagna, M.; Finzi, A. E.

    The paper presents a new approach to deal with the preliminary space mission analysis design of particularly complex trajectories focused on interplanetary targets. According to an optimisation approach, a multi-objective strategy is selected on a mixed continuous and discrete state variables domain in order to deal with possible multi-gravity assist manoeuvres (GAM) as further degrees of freedom of the problem, in terms of both number and planets sequence selection to minimize both the ?v expense and the time trip time span. A further added value to the proposed algorithm stays in that, according to planets having an atmosphere, aero-gravity assist manoeuvres (AGAM) are considered too within the overall mission design optimisation, and the consequent optimal control problem related to the aerodynamic angles history, is solved. According to the target planet different capture strategies are managed by the algorithm, the aerocapture manoeuvre too, whenever possible (e.g. Venus, Mars target planets). In order not to be trapped in local solution the Evolutionary Algorithms (EAs) have been selected to solve such a complex problem. Simulations and comparison with already designed space missions showed the ability of the proposed architecture in correctly selecting both the sequences and the planets type of either GAMs or AGAMs to optimise the selected criteria vector, in a multidisciplinary environment, switching on the optimal control problem whenever the atmospheric interaction is involved in the optimisation by the search process. Symbols δ = semi-angular deviation for GAM between the v∞ -, v∞ + inoutcoming vectors [rad] φ = Angular deviation for AGAM between the v∞ -, v∞ + inoutcoming vectors [rad] ρ = Atmospheric density [kgm-3 ] γ = Flight path angle [rad] µ = Bank angle [rad] δ?ttransf j = j-th heliocentric transfer time variation with respect to the linked conics solution ?|v∞| = Relative velocity losses because of drag [ms-1 ] ωI = i

  19. 增升装置气动噪声研究现状与发展趋势%Current Status and Future Trend for Aero-acoustics Research on High-lift Devices

    Institute of Scientific and Technical Information of China (English)

    邓一菊; 段卓毅; 侯银珠

    2012-01-01

    在对绿色航空发展要求、噪声适航标准、机体噪声概念介绍的基础上,对增升装置气动噪声进行了详细论述,包括数值分析技术、试验研究、飞行试验、降噪设计等的研究现状;阐述了增升装置气动噪声研究的重要性,提出重视机理研究和数值分析方法验证工作的观点,指出增升装置气动与噪声一体化设计的发展趋势。%Based on the green aviation requirements, FAR noise standards, air frame noise sources, the state of the art of aero-acoustics techniques including CFD, wind tunnel test, flight test and noise reduction are discussed in details. The importance of aero-acoustics research on high-lift devices is described, the viewpoint of paying regard to mechanism research and verifying by digital analysis method is presented and the future trend of high- lift devices aero-acoustics, i.e. the aero acoustics and high-lift devices integrated design, is clearly pointed out.

  20. An intercomparison and evaluation of aerosol microphysical properties among AeroCom global aerosol models of a range of complexity.

    Science.gov (United States)

    Mann, Graham; Carslaw, Ken; Reddington, Carly; Pringle, Kirsty; Schulz, Michael; Asmi, Ari

    2013-04-01

    Many of the next generation of climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. Such aerosol microphysics schemes ensure that aerosol optical properties and cloud condensation nuclei concentrations are determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study, as part of the second phase of the international AeroCom initiative, examines how the particle size distribution is simulated in the current generation of global aerosol microphysics models. We use 12 models to quantify the mean and diversity of size-resolved particle concentrations on a global scale and map areas of particular model uncertainty (based on their central diversity) and identify biases through evaluation against observations. In regions of strong anthropogenic emissions, the diversity of simulated concentrations of particles larger than 30nm (N30) is large (factor 2 to 6), while the diversity of sulphate mass (factor 1.2 to 3) and N100 (factor 1.5 to 2) are lower. We attribute the higher N30 diversity in emissions regions to inter-model differences in nucleation and growth processes, and also to different size assumptions for primary emitted particles. In clean marine regions, the pattern of size-resolved diversity is opposite to polluted regions, with N30 diversity (factor 1.5 to 2) much lower than N100. At high latitudes, N30 has relatively low diversity (factor 2 to 7), compared to much higher diversity in simulated sulphate, black carbon and N100 (factor 5 to 30). The higher N30 diversity in polluted continental regions indicates that simulated CCN concentrations are more diverse among models than the >100nm sizes, which mainly determine aerosol optical properties. However, the relatively low N30 diversity in marine and remote regions gives confidence that current global aerosol microphysics

  1. Retrospective study of the evolution of nutritional, inflammatory and bacteriological profiles of patients suffering from inoperable aero-digestive duct tumour during sequential or concomitant chemo-radiotherapy; Etude retrospective de l'evolution des profils nutritionnels, inflammatoires et bacteriologiques des patients atteints de tumeur des voies aero digestives inoperable au cours des chimioradio-therapies sequentielles ou concomitantes

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L. [Centre Guillaume-le-Conquerant, 76 - Le Havre (France); Brocard, C. [CMC Ormeaux-Vauban, 76 - Le Havre (France); Coudray, C. [Hopital Monod, 76 - Montivilliers (France); Pavlovitch, J.M. [Clinique du Petit-Colmoulin, 76 - Harfleur (France)

    2010-10-15

    The authors report a retrospective study which aimed at analysing a cohort of consecutive patients in terms of clinic and biological aspects reflecting their nutritional and inflammatory status as well as the status of their buccal bacterial flora during a sequential or concomitant chemo-radiotherapy. The objective was to detect a possible difference between these both therapeutic modalities, and a possible relationship with toxicity. Several data have been collected for patients suffering from inoperable aero-digestive tract tumour: weight, body mass index, prealbumin, albumin, orosomucoid, C-reactive protein, PINI index, and buccal bacterial flora. The evolution of these nutritional biological criteria appears to depend on the treatment modality. Short communication

  2. Late xerostomia after intensity-modulated conformational radiotherapy of upper aero-digestive tract cancers: study 2004-03 by the head and neck oncology and radiotherapy Group (Gortec); Xerostomie tardive apres radiotherapie conformationnelle avec modulation d'intensite des cancers des voies aero-digestives superieures: etude 2004-03 du Groupe oncologie et radiotherapie de la tete et du cou (Gortec)

    Energy Technology Data Exchange (ETDEWEB)

    Toledano, I.; Lapeyre, M. [Centre Jean-Perrin, 63 - Clermont-Ferrand (France); Graff, P. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Serre, C. [Centre Val d' Aurelle, 34 - Montpellier (France); Bensadoun, R.J. [CHU La Miletrie, 86 - Poitiers (France); Bensadoun, R.J.; Ortholan, C. [Centre Antoine-Lacassagne, 06 - Nice (France); Calais, G. [CHU Bretonneau, 37 - Tours (France); Alfonsi, M. [Institut Sainte-Catherine, 84 - Avignon (France); Giraud, P. [Institut Curie, 75 - Paris (France); Hopital europeen Georges-Pompidou, 75 - Paris (France); Racadot, S. [Centre Leon-Berrard, 69 - Lyon (France)

    2010-10-15

    The authors report a retrospective assessment of late xerostomia according to the RTOG (Radiation Therapy Oncology Group) classification of the European Organization for Research and Treatment of Cancer (EORTC) among patients treated by intensity-modulated conformational radiotherapy (IMRT) and suffering from upper aero-digestive tract carcinomas of different stages. Some of these patients have bee operated, and some have been treated by chemotherapy. It appears that the IMRT results in a reduction of late xerostomia, and even in an absence of salivary toxicity. Short communication

  3. New aero-gravity results from the Arctic: Linking the latest Cretaceous-early Cenozoic plate kinematics of the North Atlantic and Arctic Ocean

    DEFF Research Database (Denmark)

    Døssing, Arne; Hopper, J.R.; Olesen, Arne Vestergaard

    2013-01-01

    The tectonic history of the Arctic Ocean remains poorly resolved and highly controversial. Details regarding break up of the Lomonosov Ridge from the Barents-Kara shelf margins and the establishment of seafloor spreading in the Cenozoic Eurasia Basin are unresolved. Significantly, the plate...... tectonic evolution of the Mesozoic Amerasia Basin is essentially unknown. The Arctic Ocean north of Greenland is at a critical juncture that formed at the locus of a Mesozoic three-plate setting between the Lomonosov Ridge, Greenland, and North America. In addition, the area is close to the European plate...... plateau against an important fault zone north of Greenland. Our results provide new constraints for Cretaceous-Cenozoic plate reconstructions of the Arctic. Key Points Presentation of the largest aero-gravity survey acquired over the Arctic Ocean Plate tectonic link between Atlantic and Arctic spreading...

  4. Real-time analysis of ambient organic aerosols using aerosol flowing atmospheric-pressure afterglow mass spectrometry (AeroFAPA-MS)

    Science.gov (United States)

    Brüggemann, Martin; Karu, Einar; Stelzer, Torsten; Hoffmann, Thorsten

    2015-04-01

    Organic aerosol accounts for a major fraction of atmospheric aerosols and has implications on the earth's climate and human health. However, due to the chemical complexity its measurement remains a major challenge for analytical instrumentation.1 Here, we present the development, characterization and application of a new soft ionization technique that allows mass spectrometric real-time detection of organic compounds in ambient aerosols. The aerosol flowing atmospheric-pressure afterglow (AeroFAPA) ion source utilizes a helium glow discharge plasma to produce excited helium species and primary reagent ions. Ionization of the analytes occurs in the afterglow region after thermal desorption and results mainly in intact molecular ions, facilitating the interpretation of the acquired mass spectra. In the past, similar approaches were used to detect pesticides, explosives or illicit drugs on a variety of surfaces.2,3 In contrast, the AeroFAPA source operates 'online' and allows the detection of organic compounds in aerosols without a prior precipitation or sampling step. To our knowledge, this is the first application of an atmospheric-pressure glow discharge ionization technique to ambient aerosol samples. We illustrate that changes in aerosol composition and concentration are detected on the time scale of seconds and in the ng-m-3 range. Additionally, the successful application of AeroFAPA-MS during a field study in a mixed forest region in Central Europe is presented. Several oxidation products of monoterpenes were clearly identified using the possibility to perform tandem MS experiments. The acquired data are in agreement with previous studies and demonstrate that AeroFAPA-MS is a suitable tool for organic aerosol analysis. Furthermore, these results reveal the potential of this technique to enable new insights into aerosol formation, growth and transformation in the atmosphere. References: 1) IPCC, 2013: Summary for Policymakers. In: Climate Change 2013: The

  5. 无人机航放测量新技术的示范应用%The applied demonstration of new drone aero-radiometric technique

    Institute of Scientific and Technical Information of China (English)

    高国林; 邱崇涛; 王景丹; 沈正新; 李江坤

    2016-01-01

    基于我国首套无人机平台的航放测量系统,简要介绍了无人机航放探测原理及校准、测量、数据处理等技术;通过在新疆克拉玛依和喀什等地区开展的应用示范工作,获取了内容丰富的无人机航放测量结果;结合地质、遥感资料以及岩石放射性参数、航放异常检查结果,对区域航放特征和局部航放异常进行综合分析评价,说明了该技术在基础地质调查、放射性矿产勘查和非放射性矿产调查中的有效性;最后对比有人机和无人机的航放测量效果并进行了简单评价.%Based on the first airborne gamma ray spectrometer on the drone in China,this paper briefly described related techniques such as principle,calibration, measurement,and data processing.Through the demonstration surveys in both Karamay and Kashi,rich re-sults of aero radiometric survey were obtained.Combined with regional geology,remote sensing data,radioactivity characteristics of rocks and the results of ground-checking,the authors analyzed and evaluated the regional features and the local anomalies of aero-radiometric survey comprehensively.The results show that the technique is an effective method in such aspects as basic geological investigation and exploration of radioactive and non-radioactive mineral resource.Finally,the measurement technique was evaluated briefly for the drone based on the fix-wing craft.

  6. AeroADL: applying the integration of the Suomi-NPP science algorithms with the Algorithm Development Library to the calibration and validation task

    Science.gov (United States)

    Houchin, J. S.

    2014-09-01

    A common problem for the off-line validation of the calibration algorithms and algorithm coefficients is being able to run science data through the exact same software used for on-line calibration of that data. The Joint Polar Satellite System (JPSS) program solved part of this problem by making the Algorithm Development Library (ADL) available, which allows the operational algorithm code to be compiled and run on a desktop Linux workstation using flat file input and output. However, this solved only part of the problem, as the toolkit and methods to initiate the processing of data through the algorithms were geared specifically toward the algorithm developer, not the calibration analyst. In algorithm development mode, a limited number of sets of test data are staged for the algorithm once, and then run through the algorithm over and over as the software is developed and debugged. In calibration analyst mode, we are continually running new data sets through the algorithm, which requires significant effort to stage each of those data sets for the algorithm without additional tools. AeroADL solves this second problem by providing a set of scripts that wrap the ADL tools, providing both efficient means to stage and process an input data set, to override static calibration coefficient look-up-tables (LUT) with experimental versions of those tables, and to manage a library containing multiple versions of each of the static LUT files in such a way that the correct set of LUTs required for each algorithm are automatically provided to the algorithm without analyst effort. Using AeroADL, The Aerospace Corporation's analyst team has demonstrated the ability to quickly and efficiently perform analysis tasks for both the VIIRS and OMPS sensors with minimal training on the software tools.

  7. Solar Tower Experiments for Radiometric Calibration and Validation of Infrared Imaging Assets and Analysis Tools for Entry Aero-Heating Measurements

    Science.gov (United States)

    Splinter, Scott C.; Daryabeigi, Kamran; Horvath, Thomas J.; Mercer, David C.; Ghanbari, Cheryl M.; Ross, Martin N.; Tietjen, Alan; Schwartz, Richard J.

    2008-01-01

    The NASA Engineering and Safety Center sponsored Hypersonic Thermodynamic Infrared Measurements assessment team has a task to perform radiometric calibration and validation of land-based and airborne infrared imaging assets and tools for remote thermographic imaging. The IR assets and tools will be used for thermographic imaging of the Space Shuttle Orbiter during entry aero-heating to provide flight boundary layer transition thermography data that could be utilized for calibration and validation of empirical and theoretical aero-heating tools. A series of tests at the Sandia National Laboratories National Solar Thermal Test Facility were designed for this task where reflected solar radiation from a field of heliostats was used to heat a 4 foot by 4 foot test panel consisting of LI 900 ceramic tiles located on top of the 200 foot tall Solar Tower. The test panel provided an Orbiter-like entry temperature for the purposes of radiometric calibration and validation. The Solar Tower provided an ideal test bed for this series of radiometric calibration and validation tests because it had the potential to rapidly heat the large test panel to spatially uniform and non-uniform elevated temperatures. Also, the unsheltered-open-air environment of the Solar Tower was conducive to obtaining unobstructed radiometric data by land-based and airborne IR imaging assets. Various thermocouples installed on the test panel and an infrared imager located in close proximity to the test panel were used to obtain surface temperature measurements for evaluation and calibration of the radiometric data from the infrared imaging assets. The overall test environment, test article, test approach, and typical test results are discussed.

  8. 竹群落空气负离子及空气质量评价%Bamboo Community Aero-anion and Air Quality Evaluation

    Institute of Scientific and Technical Information of China (English)

    崔会平; 张建国; 徐文俊; 卓庆卿

    2013-01-01

    During December, 2010~November,2011,this paper monitored the aero-anion concentration and inhalable particle con-centration of scattered born bamboo , bushes bamboo and cover bamboo by aero-anion measuring instrument .It also discussed the re-lationship between aero-anion concentration and temperature and humidity .The research results showed that the aero-anion concen-tration had evident daily changes characteristics with the changes of time .There was a single-peak curve with peaks and troughs ap-peared alternately , during 8∶00~18∶00, the aero-anion concentration was highest at 8∶00 am and was lowest at 12∶00 am.The aer-o-anion concentration showed a certain regularity that it was very low in spring ,increased quickly in Summer , and decreased in Au-tumn.The bamboo community inhalable particle concentration daily change was that the inhalable particle concentration began de -creasing at 8∶00 am slowly, and the minimum appeared at 16∶00 am and then increased slowly .The seasons change was winter >au-tumn>spring>summer.Air negative ions concentration overall levels were more than 700 ones· cm-3 , beneficial to human body health, had the health functions; the air quality evaluation coefficient CI mean value was 0.892, The levels of them respectively were A level ( clear degree ) .Aero-anion concentration , temperature and relative humidity appeared a quadratic curve .%于2010年12月-2011年11月,对散生竹、丛生竹、地被竹等3种竹群落的空气负离子浓度、可吸入颗粒物浓度进行监测,采用单极系数( q)、空气质量评价指数( CI)和森林空气离子评价指数( FCI)对空气质量进行评价,并探讨竹群落空气负离子浓度与温度、湿度的相关关系。结果表明:竹群落空气负离子浓度具有明显的日变化特征:波谷和波峰交替出现的单峰曲线,在8∶00-18∶00时段内,负离子浓度在8∶00处于最高水平,而在12∶00处于最低水平;空

  9. Improvement of Laval nozzle calculation model and simulative verification in aero-engine performance calculation%拉瓦尔喷管计算模型的改进及其整机仿真验证

    Institute of Scientific and Technical Information of China (English)

    周文祥; 黄金泉; 周人治

    2009-01-01

    根据拉瓦尔喷管的典型工作状态.建立了零维拉瓦尔喷管气体动力学模型,并将其集成到发动机整机部件级模型中,开展了发动机整机加速动态仿真.仿真结果表明:①随着喷口面积的不断收小,发动机低压转速加速曲线存在一段"先降后升"区域,这与实际试车结果吻合;②贴口正激波被推出管外的瞬间,出口马赫数从亚声速突变至超声速,但喷管出口流量、发动机推力变化连续,未见突变现象.%By analyzing typical operating regimes of Laval nozzle, a zero-dimensional pneumatic model was built to evaluate the influence of Laval nozzle on the performance of aero-engine. The Laval nozzle model was integrated into a whole aero-engine component-level model. Numerical simulations were performed to study transient performance of aero-engine when nozzle throat and outlet areas decreased during accelerating process from idle to middle state. Results show that low pressure rotor speed decreases during some specific regimes, along with the reduction of Laval nozzle area in accelerating process, which also exists in real aero-engine rig tests. Besides, after normal shock clinging to nozzle outlet section was pushed out, there was a mach number break from subsonic to supersonic in nozzle outlet section, however, both the outflow rate and thrust changed smoothly without any break at the accelerating curve.

  10. Sideband Difference Diagnostics of Local Defects for Aero-engine Intershaft Bearing%航空发动机中介轴承局部故障边带差值诊断法

    Institute of Scientific and Technical Information of China (English)

    邓巍; 廖明夫; 马振国

    2012-01-01

    Aiming at the problem of difficult to diagnose local defects of aero-engine intershaft bearing, a new diag- nosis approach of sideband difference diagnostics of local defects for aero-engine intershaft bearing was proposed in this paper. Based on operating characteristic of intershaft bearing for both inner and outer ring rotation, the ap- proach used signal modulation frequency sideband as the main fault information, and established a complete set of fault diagnosis procedure. Experiments of an aero-engine inter bearing with the outer ring failure were carried out. Using the proposed approach, the local defects of the bearing was judged accurately. The theoretical analysis and fault bearing diagnosis example showed that the method can identify local defects of intershaft bearing and is effec- tive in local defects diagnosis for the aero-engine intershaft bearing%针对航空发动机中介轴承局部故障难以诊断的问题,提出了航空发动机中介轴承局部故障边带差值诊断法。该方法利用中介轴承内外环均旋转的运转特点,将其故障振动信号的调制边频带分量作为故障信息,建立了一套完整的故障诊断步骤,在实验器上对具有外环剥落故障的某型中介轴承进行实验,准确判断了该轴承故障。理论分析和诊断实例表明,该方法可以识别中介轴承局部故障,是一种适合航空发动机中介轴承局部故障诊断的有效方法。

  11. Modeling, Analysis, and Control of a Hypersonic Vehicle with Significant Aero-Thermo-Elastic-Propulsion Interactions: Elastic, Thermal and Mass Uncertainty

    Science.gov (United States)

    Khatri, Jaidev

    This thesis examines themodeling, analysis, and control system design issues for scramjet powered hypersonic vehicles. A nonlinear three degrees of freedom longitudinal model which includes aero-propulsion-elasticity effects was used for all analyses. This model is based upon classical compressible flow and Euler-Bernouli structural concepts. Higher fidelity computational fluid dynamics and finite element methods are needed for more precise intermediate and final evaluations. The methods presented within this thesis were shown to be useful for guiding initial control relevant design. The model was used to examine the vehicle's static and dynamic characteristics over the vehicle's trimmable region. The vehicle has significant longitudinal coupling between the fuel equivalency ratio (FER) and the flight path angle (FPA). For control system design, a two-input two-output plant (FER - elevator to speed-FPA) with 11 states (including 3 flexible modes) was used. Velocity, FPA, and pitch were assumed to be available for feedback. Aerodynamic heat modeling and design for the assumed TPS was incorporated to original Bolender's model to study the change in static and dynamic properties. De-centralized control stability, feasibility and limitations issues were dealt with the change in TPS elasticity, mass and physical dimension. The impact of elasticity due to TPS mass, TPS physical dimension as well as prolonged heating was also analyzed to understand performance limitations of de-centralized control designed for nominal model.

  12. Application of computational fluid dynamics to the development of compressors for aero jet engines; Koku engine yo asshukuki kaihatsu eno CFD tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, K.; Suga, S.; Matsuoka, A.; Sakai, Y. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1997-07-20

    This paper describes studies on application of computational fluid dynamics (CFD) to the development of compressors for aero jet engines, and development of highly-loaded compressor cascade of blades. The compressor used for validation is a single-stage axial-flow transonic compressor using rotor blades with low aspect ratio, whose circumferential velocity at their tips is about 430 m/s and the relative inflow Mach number reaches 1.3. The numerical analysis used a three-dimensional viscosity analysis code based on a high-accuracy upwind scheme using as a governing equation the Navier-Stokes equation for time averaging of three-dimensional compressibility of ideal gas. The calculations were executed on models with two patterns of with or without clearance on the tip of a rotor blade. The calculations were conducted at the design rotation speed and with multiple number of flow rates. The estimation accuracy on the whole performance was evaluated by using the comparison with the test result. The calculations were found 2-4% higher than the experimental values. The maximum flow rate agreed well with the experimental value. A high-performance tandem cascade of rotor blades was developed newly by utilizing the CFD analysis. As a result, the pressure ratio has increased up to 2.7 far exceeding the conventional maximum value of 1.8. A pressure ratio as high as about 50% has been achieved. 9 figs., 1 tab.

  13. Forecasting olive crop yields based on long-term aero biological data series and bio climatic conditions for the southern Iberian Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera, F.; Ruiz-Valenzuela, L.

    2014-06-01

    In the present study, bio-meteorological models for predicting olive-crop production in the southern Iberian Peninsula were developed. These covered a 16-year period: 1994-2009. The forecasting models were constructed using the partial least-squares regression method, taking the annual olive yield as the dependent variable, and both aero biological and meteorological parameters as the independent variables. Two regression models were built for the prediction of crop production prior to the final harvest at two different times of the year: July and November. The percentage variance explained by the models was between 83% and 93%. Through these forecasting models, the main factors that influence olive-crop yield were identified. Pollen index and accumulated precipitation, especially as rain recorded during the pre-flowering months, were the most important parameters for providing an explanation of fluctuations in fruit production. The temperature recorded during the two months preceding budburst was another important variable, which showed positive effects on the final yield. The July model that provides accurate predictions of fruit production eight months prior to the final harvest is proposed as an optimal model to forecast fruit produced by olive trees in western Mediterranean areas. (Author)

  14. A-Train Aerosol Observations Preliminary Comparisons with AeroCom Models and Pathways to Observationally Based All-Sky Estimates

    Science.gov (United States)

    Redemann, J.; Livingston, J.; Shinozuka, Y.; Kacenelenbogen, M.; Russell, P.; LeBlanc, S.; Vaughan, M.; Ferrare, R.; Hostetler, C.; Rogers, R.; hide

    2014-01-01

    We have developed a technique for combining CALIOP aerosol backscatter, MODIS spectral AOD (aerosol optical depth), and OMI AAOD (absorption aerosol optical depth) retrievals for the purpose of estimating full spectral sets of aerosol radiative properties, and ultimately for calculating the 3-D distribution of direct aerosol radiative forcing. We present results using one year of data collected in 2007 and show comparisons of the aerosol radiative property estimates to collocated AERONET retrievals. Use of the recently released MODIS Collection 6 data for aerosol optical depths derived with the dark target and deep blue algorithms has extended the coverage of the multi-sensor estimates towards higher latitudes. We compare the spatio-temporal distribution of our multi-sensor aerosol retrievals and calculations of seasonal clear-sky aerosol radiative forcing based on the aerosol retrievals to values derived from four models that participated in the latest AeroCom model intercomparison initiative. We find significant inter-model differences, in particular for the aerosol single scattering albedo, which can be evaluated using the multi-sensor A-Train retrievals. We discuss the major challenges that exist in extending our clear-sky results to all-sky conditions. On the basis of comparisons to suborbital measurements, we present some of the limitations of the MODIS and CALIOP retrievals in the presence of adjacent or underlying clouds. Strategies for meeting these challenges are discussed.

  15. Application of the CALIOP Layer Product to Evaluate the Vertical Distribution of Aerosols Estimated by Global Models: AeroCom Phase I Results

    Science.gov (United States)

    Koffi, Brigitte; Schulz, Michael; Breon, Francois-Marie; Griesfeller, Jan; Winker, David; Balkanski, Yves; Bauer, Susanne; Berntsen, Terje; Chin, Mian; Collins, William D.; hide

    2012-01-01

    The CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution of aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub-continental regions representative of industrial, dust, and biomass burning pollution, from CALIOP 2007-2009 observations and from AeroCom (Aerosol Comparisons between Observations and Models) 2000 simulations. An extinction mean height diagnostic (Z-alpha) is defined to quantitatively assess the models' performance. It is calculated over the 0-6 km and 0-10 km altitude ranges by weighting the altitude of each 100 m altitude layer by its aerosol extinction coefficient. The mean extinction profiles derived from CALIOP layer products provide consistent regional and seasonal specificities and a low inter-annual variability. While the outputs from most models are significantly correlated with the observed Z-alpha climatologies, some do better than others, and 2 of the 12 models perform particularly well in all seasons. Over industrial and maritime regions, most models show higher Z-alpha than observed by CALIOP, whereas over the African and Chinese dust source regions, Z-alpha is underestimated during Northern Hemisphere Spring and Summer. The positive model bias in Z-alpha is mainly due to an overestimate of the extinction above 6 km. Potential CALIOP and model limitations, and methodological factors that might contribute to the differences are discussed.

  16. 气动-引力辅助轨道机动轨迹优化方法%Trajectory Optimization Method of Aero-Gravity Assist Orbital Maneuver

    Institute of Scientific and Technical Information of China (English)

    张万里; 王常虹; 夏红伟; 解伟男

    2011-01-01

    In order to achieve the orbit maneuver and save the fuel consumption in the space travel mission of spacecrafts, the dynamic equations and performance index functions of aero-gravity assist ( AGA) maneuver were established under the terminal constraints and path constraints. The continuous two-point boundary value problem was converted to the equivalent nonlinear programming problem using the pseudospectral method, and the optimal trajectories corresponding to the maximum and minimum heliocentric velocities of the spacecraft were obtained with SNOPT software. Finally, a simulation was made for the trajectory optimization algorithm, and the variation of optimal trajectories under the peak constraint of heat flow rate was obtained. The results show that the maximum velocity deviation is 0.009 m/s when the number of nodes is 40, which satisfy the convergence precision demand. In the AGA maneuver, the maximum heliocentric velocity increases by 8.02% , the minimum heliocentric velocity reduces by 32.26% , and the corresponding deflection angles increase by 42.74° and 68.40°, respectively, when compared with those in the gravity-assist orbit maneuver. When the peak heat flow rate is 500 W/( cm2 · s) , the depth of spacecraft into the atmosphere, the heliocentric velocity, and the deflection angle reduce 6.35 km, 93 m/s, and 6°, respectively, compared with those without heat flow rate constraint.%为使航天器在星际航行中实现轨道机动且有效节省燃料,建立了ACA( aero-gravity assist)机动的动力学方程和性能指标函数,给出终端约束和路径约束条件,用拟谱法将连续两点边值问题转换为等价的非线性规划问题,应用SNOPT软件求出飞行器最大化日心速度和最小化日心速度对应的最优轨迹,最后对轨迹优化算法进行了仿真,得出在热流速率峰值约束下的最优轨迹变化规律.结果表明,节点数为40时,最大速度偏差为0.009 m/s,满足收敛精度要求;与引力辅

  17. Impact of Clocking on the Aero-Thermodynamics of a Second Stator tested in a One and a Half Stage HP Turbine

    Institute of Scientific and Technical Information of China (English)

    N. Billiard; G. Paniagua; R. Dénos

    2008-01-01

    This paper focuses on the experimental investigation of the time-averaged and time-accurate aero-thermodynamics of a second stator tested in a 1.5 stage high-pressure turbine. The effect of clocking on aerodynamic and heat transfer are investigated. Tests are performed under engine representative conditions in the VKI compression tube CT3. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the first and the second stator. Probes located upstream and downstream of the second stator provide the thermodynamic conditions of the flow field. On the second stator airfoil, measurements are taken around the blade profile at 15, 50 and 85% span with pressure sensors and thin-film gauges. Both time-averaged and time-resolved aspects of the flow field are addressed. Regarding the time-averaged results, clocking effects are mainly observed within the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, hence affecting the overall airfoil performance. For one clocking position,the thermal load of the airfoil is noticeably reduced. Pressure fluctuations are attributed to the passage of the upstream transonic rotor and its associated pressure gradients. The pattern of these fluctuations changes noticeably as a function of docking. The time-resolved variations of heat flux and static pressure are analyzed together showing that the major effect is due to a potential interaction. The time-resolved pressure distribution integrated along the second stator surface yields the unsteady forces on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

  18. Long-Term Alcohol Consumption and Breast, Upper Aero-Digestive Tract and Colorectal Cancer Risk: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Jayasekara, Harindra; MacInnis, Robert J; Room, Robin; English, Dallas R

    2016-05-01

    Cancers of female breast, upper aero-digestive tract (UADT) (oral cavity, pharynx, larynx, oesophagus) and colorectum are causally related to alcohol consumption. Although alcohol consumption is likely to vary during life, the few studies that have explicitly measured lifetime consumption or intake over time have not been summarised. We therefore conducted a systematic review and meta-analysis. Studies were identified by searching the Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature) and Scopus databases through January 2015 using broad search criteria. Studies reporting relative risks (RR) for quantitatively defined categories of alcohol consumption over time for breast, UADT or colorectal cancer were eligible. A two-stage random-effects meta-analysis was used to estimate a dose-response relationship between alcohol intake and each cancer site. RRs were also calculated for the highest relative to the lowest intake category. Sixteen articles for breast, 16 for UADT and 7 for colorectal cancer met the eligibility criteria. We observed a weak non-linear dose-response relationship for breast cancer and positive linear dose-response relationships for UADT and colorectal cancer. The pooled RRs were 1.28 (95% confidence interval, CI: 1.07, 1.52) for breast, 2.83 (95% CI: 1.73, 4.62) for UADT, 4.84 (95% CI: 2.51, 9.32) for oral cavity and pharynx, 2.25 (95% CI: 1.49, 3.42) for larynx, 6.71 (95% CI: 4.21, 10.70) for oesophageal and 1.49 (95% CI: 1.27, 1.74) for colorectal cancer. Our findings confirm dose-dependent associations between long-term alcohol intake and breast, UADT and colorectal cancer. © The Author 2015. Medical Council on Alcohol and Oxford University Press. All rights reserved.

  19. 航空电机软轴磨削烧伤研究%Research on Grinding Burn of Flexible Shaft of Aero Dynamo

    Institute of Scientific and Technical Information of China (English)

    史晓阳

    2015-01-01

    为了避免电机软轴在磨削加工过程中产生表面“烧伤”缺陷,防止其在交变载荷下发生非正常断裂,造成严重故障。通过分析软轴加工过程中磨削烧伤产生的机理和磨削“烧伤”的检测方法,确定了影响软轴磨削“烧伤”的因素,并制定了针对性改进加工工艺措施和软轴磨削“烧伤”检测方法。经验证,改进措施可以提高软轴加工的质量,有效降低加工废品率,并避免微缺陷工件漏检。%The paper is to prevent flexible shaft of aero dynamo from being burned in the process of abrasive machining ,and avoid abnormal rupture under alternating load ,thus resulting in serious failures .T hrough analyzing the mechanism of grinding burn in the process of flexible shaft machining and the detection meth‐od of grinding burn ,the paper finds out the factors affecting the grinding burn of flexible shaft ,and works out the measures for improving the machining technique and the method for detecting grinding burn .Upon the verification ,the measures can enhancing the quality of flexible shaft machining ,reduce the rejection rate ,and avoid the missing inspection of slightly defective shafts .

  20. 航空发动机空气系统验算标定%Calibration of Calculation for Aero-Engine Air System

    Institute of Scientific and Technical Information of China (English)

    呼艳丽; 徐连强; 赵维维

    2014-01-01

    利用流量特性试验得到的相关流路元件的流阻计算模型,和旋转状态下阶梯齿风阻温升计算方法,通过调节封严篦齿间隙等参数,对航空发动机空气系统的压力、温度进行验算标定,并根据验算结果分析发现后续试验中存在和需要注意的问题。验算标定结果表明:通过对发动机试验工况的验算标定,可发现试验中存在的问题,较准确地模拟出后续试验中的问题和试验风险,确保发动机的工作安全,并为空气系统的进一步改进和优化提供依据。%A calibration method for aero-engine air system was presented, with the air system throttle ele-ments flow loss coefficient experiment data and the rotating step labyrinth seal windage temperature rise cal-culation method. The pressure and temperature of air system were calibrated by adjusting the labyrinth seal clearance. Some possible and noteworthy problems in the following tests were found out according to the cal-ibrated results. The results show that through the calibration of experimental conditions, the problems could be revealed and the risk of the following tests can be simulated perfectly to ensure the safety of engine work-ing which could be referential for the further improvements of engine's air system.

  1. Modeling and experimental study of the mechanism of electrification from aero-engine jet%航空发动机喷流起电机理建模与试验研究

    Institute of Scientific and Technical Information of China (English)

    朱利; 刘尚合; 郑会志; 魏明; 胡小锋; 索罗金·安德烈

    2013-01-01

    以研究航空发动机喷流起电的机理以及喷流起电对飞行器整体带电特性的影响为目的,对起电机理进行了建模和实验验证。首先以流体运动方程为基础,建立了航空发动机带电粒子浓度的动态仿真模型,仿真得到发动机燃烧过程中的各类粒子浓度变化情况。其次,设计了用于发动机喷流起电探测的静电感应传感器,对装配涡扇发动机的某型飞行器进行了地面试验测试,得到了发动机启动、稳定运行、加速、减速、停止等状态的动态电位。仿真及实验结果详细地描述了发动机喷流起电的机理,以及喷流起电会使飞行器带负电的结论,为进一步分析飞行器飞行过程中整体带电特性提供了指导。%To investigate the mechanism of electrification from aero-engine jet and the electrification effect on the overall charging charac-teristics of vehicle, a simulation model of concentration of charged particles in aero-engine is build based on the equations of fluid motion. And concentration changes of various particles are simulated. To verify the simulation result, a special electrostatic induction sensor for detecting the electrification of engine jet is designed, according to the principle of the Faraday cup, to measure the dynamic potential when the turbofan engine starts, operates steadily, accelerates, decelerates and stops. The simulation and experimental re-sults show that the aircraft is negatively charged by the electrification from aero-engine jet and the mechanism of electrification from aero-engine jet is described specifically. The research may provide a guidance to the further study on analyzing the overall charging characteristics of vehicle during the flight.

  2. Grey Comprehensive Evaluation of Cutting Tool Performance for Aero-engine Blisk%航空发动机整体叶盘刀具性能灰色综合评价

    Institute of Scientific and Technical Information of China (English)

    贾玉佩; 赵威; 李亮

    2016-01-01

    A grey comprehensive evaluation method of CNC milling tool performance was pro—posed for an aero-engine titanium alloy blisk with the CNC milling of a type of aero-engine blisk as the research obj ect.In this method,a benchmark with some typical difficult-to-machine features extracted from aero-engine blisk was designed,and the processing route was developed.In addition,grey com—prehensive evaluation models of cutting tool performance were established for roughing and finishing tools respectively.Finally,experiments of CNC milling the benchmark were carried out,and then the grey comprehensive evaluation models were used to evaluate the cutting tools.The results show that the method is convenient and effective to evaluate the cutting tool performance for aero-engine blisks.%以某型航空发动机钛合金整体叶盘的数控铣削为研究对象,提出了一种面向航空发动机整体叶盘的数控铣削刀具性能灰色综合评价方法。首先设计涵盖航空发动机整体叶盘难加工特征的基准件模型,然后基于灰色关联度分别构建了粗精加工刀具性能灰色综合评价模型,最后进行基准件的切削试验并应用所建立的灰色综合评价模型对刀具性能进行综合评价。研究结果表明,所构建的基准件模型和灰色综合评价模型可以快捷、有效地评价刀具性能。

  3. What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3-UKCA and inter-model variation from AeroCom Phase II

    Science.gov (United States)

    Kipling, Z.; Stier, P.; Johnson, C. E.; Mann, G. W.; Bellouin, N.; Bauer, S. E.; Bergman, T.; Chin, M.; Diehl, T.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Kokkola, H.; Liu, X.; Luo, G.; van Noije, T.; Pringle, K. J.; von Salzen, K.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Takemura, T.; Tsigaridis, K.; Zhang, K.

    2015-09-01

    The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors, we investigate the effects of individual processes in one particular model (HadGEM3-UKCA), and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment. In this way we show that (in this model at least) the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global mean profile and zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models. Convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulphate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter). The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea-salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only. In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number, while the profiles of larger particles are controlled by the same processes as the component mass profiles, plus the size distribution of

  4. What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3-UKCA and inter-model variation from AeroCom Phase II

    Science.gov (United States)

    Kipling, Zak; Stier, Philip; Johnson, Colin E.; Mann, Graham W.; Bellouin, Nicolas; Bauer, Susanne E.; Bergman, Tommi; Chin, Mian; Diehl, Thomas; Ghan, Steven J.; Iversen, Trond; Kirkevåg, Alf; Kokkola, Harri; Liu, Xiaohong; Luo, Gan; van Noije, Twan; Pringle, Kirsty J.; von Salzen, Knut; Schulz, Michael; Seland, Øyvind; Skeie, Ragnhild B.; Takemura, Toshihiko; Tsigaridis, Kostas; Zhang, Kai

    2016-02-01

    The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors in one particular model, we investigate the effects of individual processes in HadGEM3-UKCA and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment. In this way we show that (in this model at least) the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global-mean profile and, to a lesser extent, the zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models. In HadGEM3-UKCA, convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulfate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter). The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only. In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number (e.g. total CN > 3 nm), while the profiles of larger particles (e.g. CN > 100 nm) are controlled by the

  5. What Controls the Vertical Distribution of Aerosol? Relationships Between Process Sensitivity in HadGEM3-UKCA and Inter-Model Variation from AeroCom Phase II

    Science.gov (United States)

    Kipling, Zak; Stier, Philip; Johnson, Colin E.; Mann, Graham W.; Bellouin, Nicolas; Bauer, Susanne E.; Bergman, Tommi; Chin, Mian; Diehl, Thomas; Ghan, Steven J.; Tsigaridis, Kostas

    2016-01-01

    The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors in one particular model, we investigate the effects of individual processes in HadGEM3-UKCA and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment. In this way we show that (in this model at least) the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global-mean profile and, to a lesser extent, the zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models. In HadGEM3-UKCA, convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulfate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter). The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only. In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number (e.g. total CN >3 nm), while the profiles of larger particles (e.g. CN>100 nm) are controlled by the

  6. Advanced NDT&E Techniques for Aero-materials and Structures in China%我国航空材料和结构先进无损检测技术之应用与发展

    Institute of Scientific and Technical Information of China (English)

    刘松平; 刘菲菲; 郭恩明; 李乐刚; 史俊伟

    2013-01-01

    This paper was focused on the review of advanced NDT&E techniques for aero-materials and structures (AMS) because of the increasingly much high importance of NDT&E and the developments and applications of new advanced AMS.The new progress and practical applications of advanced NDT&E techniques for aero-raw materials,light-weight metal structures and composite materials,etc.,were summarized.Multi-channel ultrasonic automated scanning technique with high resolution is very effective for reliable NDT of aero-tubes.High resolution and high sensitivity ultrasonic method and PUDE provide powerful approaches for NDT&E of lightweight metal structures,such as solid state,electronic beam,TLP,braze and laser welded structures.The advanced automated ultrasonic scanning imaging technique,whose resolution and dead-zone can reach a single ply (approximately 0.125 mm),brings the very practical robust ability in fast NDT&E of aero-composite materials and large-scale structures.Its efficiency of NDT for large-scale structures can be increased 20 times compared with traditional single-channel ultrasonic scanning technique.The visual NDT&E techniques with high resolution,sensitivity,detectability and flexibility as well as reliability are the appreciate methods for aero-AMS at the present and in the future.%针对现代航空产品及其制造工艺等特点,结合航空材料结构工艺制造过程及缺陷成因与特征,以航空原材料、轻质金属结构和复合材料为例,通过对典型技术案例的研究与应用结果,介绍了先进航空材料和结构无损检测技术的新进展与应用,浅析了先进航空材料和结构无损检测现状与问题及发展趋势.分析指出,检测的灵敏度、分辨率、可靠性、可检性和充足的试验积累与验证是现代航空材料和结构无损检测技术的核心和应用基础,快速可靠、高灵敏度、高分辨率的可视化成像检测技术是今后先进航空材料和结构无损检测的重要发展方向.

  7. 基于折射率梯度门限的气动光学窗口光传输研究%Study on Optical Transmission of Aero-optical Window Based on Refractive Index Gradient Threshold

    Institute of Scientific and Technical Information of China (English)

    李庆波; 王业芳

    2012-01-01

    基于流场界面厚度(Interfacial—Fluid—Thickness,IFT)理论,建立了高折射率梯度门限模型来研究气动光学窗口光传输畸变。首先在光学窗口折射率梯度场基础上,提出高折射率梯度门限,忽略绝对值低于该门限的折射率梯度值,重构折射率场,并对其气动光学传输效应进行仿真。结果表明,当58.37%的梯度值被忽略时,得到的重构折射率场与原折射率场仿真光程差(OPD)最大相对误差不超过1.5%,验证了气动光学窗口高折射率梯度区域是产生光传输畸变的主要原因,也证实了该门限模型对气动光学窗口光传输效应进行仿真的可行性,对气动光学失真的机理、预测及校正有一定的指导意义。%Based on the interracial-fluid-thickness theory, a high refractive index gradient threshold model of the aero-optical window is established to study the optical distortion of the aero-optical window. Based on the refractive index gradient field of the aero-optical window, a high gradient threshold of refractive index is proposed. Refractive index gradients whose abso- lute values are below the threshold are set to zero and the refractive index field is reconstructed. Optical distortions of the o- riginai and reconstructed refractive index fields are simulated of the gradient values are set to zero, the maximum relative and analyzed. The comparisons reveal that when about 58. 37 error of the optical path difference(OPD) between the original and the reconstructed refractive index fields is less than 1.5%. The results show that the high refractive index gradient re- gions of the aero-optical window are the main cause of optical distortions of the window, and it also verifies the feasibility of the threshold in the simulation for optical propagation in the aero-optical window. The research is useful for the theory, and the forecast and correction of optical distortions.

  8. Superconducting Aero Propulsion Motor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Superconducting electric propulsion systems will yield improvements in total ownership costs due to the simplicity of electric drive when compared with gas turbine...

  9. Study on Aero-anion Concentration around Different Forest in Thousand-isles Lake Reservoir%千岛湖库区不同森林植被空气负离子状况

    Institute of Scientific and Technical Information of China (English)

    宋绪忠; 许利群; 徐高福; 杨华; 岳春雷; 罗小华

    2009-01-01

    Study on aero-anion concentration in 6 different forest communities and water surface in Qiandao reservoir, Zhejiang province showed that aero-anion concentration in the whole reservoir region averaged 6 238/cm~3, indicating good for human health and high quality forest tourism. The result demonstrated that riparian forest had the highest concentration of aero-anion, topped to 21 624/cm~3, while small negative ions in evergreen broad-leaf forest were 8.91 times than that in Pinus massoniana plantations. Air clean index(CI) in riparian forest, evergreen broad-leaf forest and street trees reached 1 400.2, 958.9 and 273.3, while that in P. Massoniana plantation and street trees in office areas was the lowest of 2.4. Ions component analysis indicated that the ion polarity ratio in each forest environment was ≤0.13.%对千岛湖库区湖面及马尾松林、常绿阔叶林等6种不同森林植被中的空气负离子进行了研究,结果表明:千岛湖库区空气负离子非常丰富,平均为6 238个/cm~3,环境整体对健康非常有利,适合开展以增进健康为目的的高质量森林旅游.河岸林负离子浓度最高达21 624个/cm~3,演替顶级植被常绿阔叶林空气小分子负离子含量是主体森林类型马尾松林的8.91倍.库区空气质量普遍达到很清洁的水平,其中河岸林、常绿阔叶林、库边行道树清洁度最高,CI指数分别达到1 400.2、958.9、273.3.混交林、湖面清洁度也较高,马尾松林、林场场部行道树空气清洁度量低CI指数2.4.空气离子组成分析显示,与水体相比森林环境空气负极性更具有整体性,空气离子单极系数均≤0.13.

  10. A coupled aero-structural model of a HAWT blade for dynamic load and response prediction in time-domain for health monitoring applications

    Science.gov (United States)

    Sauder, Heather Scot

    experience for fatigue life prediction procedures. To fill in the gaps in the existing knowledge and meet the overall goal of the proposed research, the following objectives were accomplished: (a) improve the existing aeroelastic (motion- and turbulence-induced) load models to predict the response of wind turbine blade airfoils to understand its behavior in turbulent wind, (b) understand, model and predict the response of wind turbine blades in transient or gusty wind, boundary-layer wind and incoherent wind over the span of the blade, (c) understand the effects of aero-structural coupling between the along-wind, cross-wind and torsional vibrations, and finally (d) develop a computational tool using the improved time-domain load model to predict the real-time load, stress distribution and response of a given wind turbine blade during operating and parked conditions subject to a specific wind environment both in a short and long term for damage, flutter and fatigue life predictions.

  11. Initial comments on the aero geophysical information present at the B and C areas of the Itatira (Brazil) project; Comentarios iniciais sobre as informacoes aerogeofisicas presentes nas areas B e C do Projeto Itatira

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Neivaldo Araujo de; Castelo Branco, Raimundo Mariano Gomes [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Geologia. Lab. de Geofisica de Prospeccao e Sensoriamento Remoto

    1999-07-01

    The aero geophysical project called Itatira,, accomplished by LASA Engenharia e Prospeccoes S.A., Between September and November/1977 through contract with NUCLEBRAS, corresponds to one of the first project of this gender accomplished in national territory. In this project were flight more than 80 000 km of linear lines, which covered approximately 38 000 km{sup 2} on the precambrian terrains of the Ceara State, NE Brazil. For several reasons, the total area of the project was subdivided in three sub-areas (A, B and C), each one covered by a different airship (LAS, 1977). This paper presents the geophysical information and preliminary interpretations of the areas B and C that were obtained through the integrated use of the soft wares AUTOCAD r. 14, OASIS MONTAJ r.4.2 and ERMAPPER r.5.5. (author)

  12. A Simple Exponent Extrapolation Method of Sub-idle Characteristics on Aero-engine%一种简便的叶轮部件低状态特性的指数扩展方法

    Institute of Scientific and Technical Information of China (English)

    徐鲁兵; 潘尚能; 陈竞炜

    2013-01-01

    A simple exponent extrapolation method of sub-idle characteristics on aero-engine was presented.Based on the basic theory of similarity of pump at low speed and taking the influence of air/gas compressibility into account,a correctional exponent extrapolation mathematic model was developed and was applied to supplement the sub-idle rotating component characteristics through selected two lowest speed line.The comparison between calculated results and original datas for a certain compressor and turbine characteristics indicated that this exponent extrapolation method is simple,general and has acceptable precision,and the supplemented sub-idle component characteristics can be applied to estimate the starting characteristics of aero-engine.%介绍了一种简便的航空发动机叶轮部件低状态特性的扩展方法.基于低转速泵相似理论,并考虑了空气/燃气的可压缩性影响,给出了修正的指数关系方程;针对已知的两条较低转速特性线外插得到更低转速状态的部件特性.结合已有叶轮部件特性进行有效性验证.结果表明方法具有较强的实用性、通用性和一定的精度,扩展得到的低状态部件特性可以满足发动机起动性能模拟的工程应用.

  13. 航空活塞发动机接口模拟器快速开发新技术研究%The Research on the Rapid Development Techniques for Aero Piston Engine Interface Simulator

    Institute of Scientific and Technical Information of China (English)

    周彰毅; 于兵; 张天宏

    2014-01-01

    To overcome the deficiencies of the current aero engine interface simulator, a new joint development method is presented based on DSP and MATLAB/SIMULINK. The hardware platform is designed based on DSP. Modeling with MATLAB/SIMULINK,portable embedded engine model C code is generated through RTW,and the model C code is integrated into DSP. The engine model to the interface simulator is introduced quickly and effectively,therefore,the interface simulator can simulate the states of aero engine more accurately. Test showed that this new method is feasible and effective.%针对目前航空发动机接口模拟器设计中的不足,提出了一种基于DSP+MATLAB/SIMULINK的航空活塞发动机接口模拟器联合开发新方法,基于DSP设计接口模拟器硬件平台,利用SUMULINK建立发动机模型,使用RTW从发动机模型中生成可移植的嵌入式模型C代码,通过代码集成在DSP中加入发动机模型,高效快速地解决了如何在接口模拟器中融入发动机模型的难题。所设计接口模拟器能更真实准确地模拟航空活塞发动机工作状态,试验验证了接口模拟器的可靠性和该方法的可行性。

  14. Condition Assessment for Aero -Engine Rolling Bearings Based on Posterior Probability SVM%基于后验概率 SVM的航空发动机滚动轴承状态评估

    Institute of Scientific and Technical Information of China (English)

    汪瑾; 陈果; 王洪伟; 冯康佳; 陈立波

    2015-01-01

    为了准确地进行航空发动机滚动轴承状态评估,提出了一种基于后验概率支持向量机的航空发动机滚动轴承状态评估方法。首先利用仿真数据建立了后验支持向量机模型,进行了分类试验和后验概率预测验证,然后利用航空轴承失效监控试验系统进行了滚动轴承性能退化试验,得到轴承不同工作状态的振动数据,最后利用获取的试验数据进行了滚动轴承状态评估,充分验证了该评估方法的正确性。%For assessment of condition for aero -engine rolling bearings,a method is proposed based on posterior prob-ability SVM.Firstly,the posterior probability SVMmodel is established by using simulation data,and the classification experiment and posterior probability prediction verification are carried out.Then,the performance degradation experi-ments for rolling bearings are conducted by using the aero -engine bearing failure monitoring test system,the vibration data of bearings under different working conditions is obtained.Finally,the rolling bearing condition assessment is car-ried out by using collected experiment data,and the validity of assessment method is fully verified.

  15. A Multi-Thread Data Acquisition Module for Vibration Signal of Aero-Engine%一种航空发动机振动信号多线程采集模块设计

    Institute of Scientific and Technical Information of China (English)

    金路; 廖明夫; 黄巍

    2013-01-01

    A multi-thread data acquisition module based on the NI (National Instruments)' s DAQ card is designed for the vibration signal measurement of aero-engine.Data collection and extraction are placed in different threads in order to make them synchronous.This module is designed to be a dynamic link library(DLL).Many test systems programmed with different computer languages could use it.The aero-engine has two kinds of working states:steady state and transient state.The vibration signal acquisitions in these two states have different characteristic,so that two sub-modules are designed for the two states.Due to the widely use of double rotor in aero-engine,double speed acquisition module is programmed and the corresponding data processing method is designed.The module is examined by acquiring vibration signal on site.The results show that the data loss problem in transient process is solved,the rotor speed and vabrition signal in both steady process and transient process are collected accurately and real-time.The module has been sucessfully applied to fieldmeasurement.%开发了Windows环境下基于NI公司数据采集卡的航空发动机振动测试系统通用数据采集模块.该采集模块采用了多线程技术,将数据采集和提取置于不同的线程中,以达到两者同步的目的.将该模块制作为Windows动态链接库(DLL),利用DLL资源共享特点来满足多种测试系统的调用请求.同时根据航空发动机运行过程分为稳态运行及暂态过程的特点,分别设计了对应的振动信号采集子模块,以满足不同运行状态的测试要求.由于航空发动机多为双转子,针对这一特点设计了双转速采集及数据处理程序.经过测试,该模块较好地解决了暂态过程中的数据丢失问题,能够实时准确地采集稳态过程及暂态过程的转速和振动信号,并已成功运用于现场实测.

  16. 航空静止直-直变换器并联运行建模研究%Study on Modeling of Aero Static DC/DC Convertors' Parallel Operation

    Institute of Scientific and Technical Information of China (English)

    杨会敏; 郭庆

    2011-01-01

    The DC convertor equipment plays an important role in the aero static high voltage DC power supply system, which main development is miniaturization and modularization. Existing research methods of parallel operation are not based on model, which bring localization to design the control and repair tache. In allusion to this problem, modeling of aero static DC/DC convenors'parallel operation based on control transfer function presented. On the based of the single convertor model, the multi-convertor model constructed using linear system theory. After analysis the average current tache and convertor tache, the effect of parameters studied, which provided the basis for the control and error analysis of convertor parallel operation.%在高压直流供电体制下,航空静止直-直变换器起着十分重要的电压转换作用,小型化、模块化是其发展的主要方向.现有对直-直变换器并联运行研究的方法都是不基于模型的,为其控制和补偿环节的设计带来一定的局限性.针对此问题,提出了基于控制系统传递函数模型的多直-直变换器系统并联运行建模研究.在单台变换器模型的基础上,根据线性系统相关理论,建立了多直-直变换器并联系统的模型.通过对并联系统均流环节和变换器环节的详细分析,研究了模型各部分参数对系统并联特性的影响,为后续对变换器并联运行的控制及误差分析提供了模型基础.

  17. Partition optimization in the flight envelope for control design of aero-engines%用于控制器分区设计的发动机飞行包线区域最优划分

    Institute of Scientific and Technical Information of China (English)

    李述清; 张胜修; 胡卫红

    2012-01-01

    结合最优化理论和线性系统理论,对控制问题中航空发动机飞行包线区域划分方法展开了研究.首先基于小偏离线性动态模型,根据线性系统理论,将发动机动态特性的摄动归为线性模型的状态矩阵特征值和稳态增益的摄动来表征.然后在此基础上,定义了一种广义距离以表征发动机动态特性的摄动程度,并以定义了区域的划分原则.继而提出将飞行包线区域划分问题转化为一个基于该广义距离的最优化问题.最后就某型涡扇发动机情形,对其飞行包线区域进行了划分计算,并对划分区域内发动机线性模型摄动进行了比较。结果表明该区域划分和标称点选择方法的有效性.%According to the optimization theory and linear system theory, the method of flight-envelop optimization partition for aero-engines is researched. First, linear state variable mode (LSVM) was used to describe aero-engine's dynamic characteristic of small perturbation on steady operating point, and the perturbation between LSVMs was denoted by the perturbation of coefficient matrix eigenvalues and low-frequency gains of the LSVMs. Then, a general distance based on the perturbation of eigenvalues and low-frequency gains of the LSVMs was put forward. And the problem of dividing the flight envelope and selecting the nominal points in a flight envelope was translated into a most overlay problem. Thus, based on the general distance, a set of least number of nominal points could be found to divide the flight envelope by using optimizing method. Last, a flight envelope area of a turbofan engine was divided by using this method, and the results indicated that this method was proper.

  18. Abrupt fault diagnosis of aero-engine based on affinity propagation clustering%基于相似性传播聚类的航空发动机突发故障诊断

    Institute of Scientific and Technical Information of China (English)

    李丽敏; 王仲生; 姜洪开

    2014-01-01

    针对航空发动机突发故障,构建了一种基于相似性传播聚类的突发故障诊断方法。首先利用突发故障历史监测数据建立突发故障数据库,通过相似性传播聚类找到数据库中所有突发故障数据的中心,当诊断新采集数据的突发故障类型时,通过相似性传播聚类找到当前新采集数据的中心,经过与突发故障数据库中的数据中心进行匹配判断该新采集数据所对应的突发故障类型。将该突发故障诊断方法应用到发动机转子实验台的突发故障诊断中,仿真和实验结果表明该方法的可行性,并通过与其他方法比较,表明该方法具有诊断时间短和误差小的优点。%Aiming at aero-engine faults,an abrupt fault diagnosis method based on affinity propagation clustering was proposed.Abrupt fault historical monitoring data were used to establish faults database.Through affinity propagation clustering,all the exemplars of abrupt faults in the database were found and the affinity propagation clustering was applied once again to find the exemplar of the new collected data.The fault type was then identified by matching the center with the centers obtained from the faults database.The method was used in the aero-engine abrupt fault diagnosis.The simulation and experiment results show that the method is feasible to diagnose abrupt fault,and compared with other methods,it needs shorter time consuming and produces lower error.

  19. 欧盟间冷回热循环燃气涡轮发动机发展综述%The development of intercooled recuperated cycle aero- engine in Europe Union

    Institute of Scientific and Technical Information of China (English)

    沈虹; 周军; 陈玉洁; 李茜

    2016-01-01

    As a new concept of power technology, the intercooled recuperated gas turbine engine could meet demands of cost, environmental-friendliness and fuel efficiency from future propulsion system. Struc⁃ture features and performance advantages of intercooled recuperated aero-engines (IRA) were presented;IRA engine development carried out and results achieved by EU according to 5th and 6th frameworks were al⁃so introduced in detail. Based on the characteristics of aero-engine, the key to develop new IRA engine was pointed out, that is the compact intercooler with high heat exchange efficiency and light weight as well as in⁃novative design of recuperator, and the application of intercooled recuperated cycle in aviation still faces a lot of challenges.%作为一种新概念动力技术,间冷回热循环燃气涡轮发动机可满足未来推进装置对成本控制、环境友好性和燃料高效利用等方面的要求。概述了间冷回热发动机的结构特点和性能优势,并详细介绍了欧盟根据第5和第6框架协议所开展的间冷回热涡扇发动机研发工作及取得的成果。结合航空发动机的特点,指出研制和发展新型间冷回热航空发动机的关键,在于结构紧凑、换热效率高、质量轻的间冷器和回热器的创新设计,间冷回热循环在航空领域的应用还将面临一系列挑战。

  20. 发动机吊挂与机翼连接接头强度分析与试验%Strength Analysis and Test on Connecting Joints between Aero Engine Pylon and Wing

    Institute of Scientific and Technical Information of China (English)

    孙滨; 林鸿志; 谭伟; 薛彩军

    2012-01-01

    The connecting joints between aircraft pylon and wing which are mainly used for transferring loads from aero engine are critical parts of aircraft structure and strength design. In order to analyze the joint strength as well as stress and strain distribution accurately, a static test system is established, and a finite element mod- eling method for the connecting joints is studied. Detailed finite element model is built based on the joint loads obtaining from the overall finite element model, and two serious load cases for the joints are analyzed. Compari- son of computing results and test results demonstrates that the finite element modeling method of joint strength is reasonable, which is of an application and reference value for the joint design between aero engine pylon and wing.%飞机吊挂与机翼连接接头主要用于传递来自动力装置的载荷,是飞机结构强度设计的关键件。为了精确分析吊挂与机翼连接接头强度及应力应变分布规律,设计了一套接头强度静力试验系统,研究了接头强度有限元建模方法。以总体有限元分析得到吊挂与机翼连接接头载荷为基础,建立了接头的细节有限元模型,分析了对接头强度影响较为严重的两种工况。有限元分析结果与试验结果对比,验证了接头强度有限元建模方法合理,对民机发动机吊挂与机翼接头设计具有应用参考价值。

  1. 套齿联轴器对航空发动机振动特性的影响%Effects of Gear Coupling on Aero-engine Vibration Characteristics

    Institute of Scientific and Technical Information of China (English)

    廖仲坤; 陈果; 王海飞

    2015-01-01

    The aero-engine gear coupling stiffness was studied herein ,and the coupling dynamic gearing forces were deduced ,the relationship among the gear coupling gearing forces and the torque , misalignment ,and the dynamic relative displacements was analyzed .According to aero-engine gearing structure characteristics ,a rotor dynamic model including gear coupling and the three supports was es-tablished ,and the effects of gear coupling stiffness on the system frequency response function were an-alyzed;under the conditions of considering the angle misalignment between two rotors ,the effects of gear stiffness on the misalignment responses were studied .The results show that the dynamic gearing stiffness model can simulate the gear coupling dynamic stiffness very correctly ,but the dynamic change range of the stiffness is not enough to change obviously the system dynamic characteristics , however ,the effects of the angle stiffness of gear coupling on the system vibration characteristics are very great .%研究了航空发动机套齿联轴器的连接刚度,推导了套齿动态啮合力计算模型,分析了随扭矩、套齿不对中和动态相对位移变化的套齿啮合力和啮合刚度。依据航空发动机套齿连接结构,建立了含套齿联轴器的三支点转子动力学模型,分析了套齿连接刚度对系统频率响应特性的影响,在考虑转轴间角度不对中的情况下,分析了套齿连接刚度对系统不对中响应的影响规律。结果发现,动态啮合力模型能够更加真实地模拟套齿连接刚度的变化,但是,当其径向啮合刚度变化不大时,其计算结果与等效刚度模型的计算结果相同,套齿角向刚度对系统动力性能影响很大,在套齿设计、装配和使用中需要重视。

  2. Numerical Investigation of Aerodynamic and Aero-Thermal Effects for Hypersonic Vehicles%典型外形高超声速气动力/气动热数值计算研究

    Institute of Scientific and Technical Information of China (English)

    刘毅; 王刚; 叶正寅

    2014-01-01

    Hypersonic flow field has been numerically investigated for two different configurations, to study the aer-odynamic / aero-thermal effects. Simulations were performed using an in-house hybrid unstructured Reynolds-aver-aged Navier-Stokes solver ( HUNS3D) . Four different flux differencing schemes ( central scheme and three upwind schemes AUSM+, AUSM+up, Roe) were employed for spatial discretization. The accuracy of all the schemes was compared with each other and with the available experimental data. Different levels of meshes were generated to in-vestigate the effect of grid resolution. The pressure distribution was not much influenced by the mesh resolution;however the predicted heat flux was greatly affected by the change in the mesh resolution. The shock position has been accurately captured by the Central, AUSM+and AUSM+up schemes. The predicted pressure distribution was in good agreement with the experimental data but some difference was observed in the robustness of flux differencing schemes. The increase in the wall temperature gives rise to flow separation which eventually affects the aerodynamic/ aero-thermal heating. After the separation zone the flow reattachment enhances the surface heat transfer dramatic-ally.%通过数值模拟和理论分析的综合研究,比较了网格密度不同对计算的影响,研究了中心格式和3种迎风格式( AUSM+格式、AUSM+up格式、Roe格式)的计算性能,探讨了壁面温度变化对气动力/气动热计算的影响。结果表明:网格密度变化对气动力计算影响不大,但却在很大程度上影响热流的计算及流动分离的模拟;各空间格式都能准确地计算出流场压力分布,有较高的激波分辨率,但鲁棒性有所差异,其中AUSM+up格式在高超声速流场计算中鲁棒性较好;壁面温度升高会导致所得分离区增大,气动力/气动热分布也会相应发生变化;在分离区后的流动再附会很大程度上增大该区域的热流值。

  3. 航空发动机对转涡轮气动设计技术研究进展%Aerodynamic Design of Counter-rotating Turbine for Aero-engine

    Institute of Scientific and Technical Information of China (English)

    周琨; 邹正平; 刘火星; 王雷

    2012-01-01

    随着航空工业的发展,民用或者军用飞行器都对航空发动机要求越来越高,对转涡轮由于其气动布局上的优势能成为未来航空发动机的关键技术之一.本文通过对国内外文献的调研,结合课题组多年研究工作,分析了对转涡轮内部的特征,并从对转涡轮速度三角形参数分析和气动设计准则、内部复杂流动机制、激波组织技术和收扩叶型造型方法等方面对其研究进展进行了论述;在此基础上考虑加工工艺、结构强度、传热冷却等多学科耦合因素,探讨了转涡轮技术在工程应用中面临的挑战及可能的解决方向,展望了转涡轮技术的发展趋势.%With the development of aviation industry, more and more requirements are submitted during the design of civil and military aero-engines, such as higher thrust-weight ratio, lower fuel consumption, more affordability, etc. The counter-rotating turbine technology provides a powerful solution for the problems. The relevant literatures are reviewed from the aspects of velocity triangle parametric analyses, aerodynamic design criteria, internal (low mechanisms, Shockwave control methods, and design techniques of convergent-divergent airfoils, respectively. By combining literature review with the research carried out in many years by authors, the characteristics of counter-rotating turbine are analyzed. However some challenges are also encountered when the counter-rotation turbine technology is applied to the aero-engines. These challenges in terms of processing technology, structural strength, heal transfer/cooling as well as their possible solutions are considered. Finally, the development trends of the technology are predicted.

  4. Phased Array Ultrasonic Nondestructive Testing for Aero-engine Turbine Blade%航空发动机涡轮叶片相控阵超声检测研究

    Institute of Scientific and Technical Information of China (English)

    江文文; 柏逢明

    2011-01-01

    超声波无损检测技术(UNT)是航空工件检测中应用较多的一种检测方法.本文对航空发动机涡轮叶片进行了超声波无损检测;传统检测是用反射波形和波幅特征分析检测出发动机涡轮叶片缺陷;相控阵超声检测(PAUT)是利用相位延迟达到相控效果,形成清晰的图像,和传统超声波检测相比,更能直观的显示缺陷的位置和形状.%Ultrasonic Nondestructive Testing (UNT) is widely used in aviation component test .This paper adopts UNT in aero-engine turbine blade .Traditional detection uses reflection waveform and amplitude characteristic to check out flaw in engine turbine blade . Phased Array Ultrasonic nondestructive Testing (PAUT) takes advantage of phased delay to obtain phased effect and product clear image .Comparing with traditional ultrasonic detection, PAUT shows position and sharp of flaw more directly.

  5. 飞机航向对航空磁探仪搜潜概率影响的仿真%Simulation Study on Effect of Aero Flight Orientation on Searching Submarine Probability of Airborne Magnetic Anomaly Detector

    Institute of Scientific and Technical Information of China (English)

    曲晓慧; 陈建勇; 单志超

    2014-01-01

    The submarine is looked upon as a magnetic dipole possessing three axis magnetic moment in this paper and the factor of its course is considered. The expression of magnetic field based on submarine as the center of orthogonal reference frame is educed and mathematics model of airborne Magnetic Anomaly Detector (MAD) searching submarine is established. The effect of aero flight orientation on searching submarine probability of airborne MAD is simulated by using of Monte Carlo method. The simulation result shows that aeroplane should fly from south to north or contrarily when MAD is used to searching submarine.%将潜艇作为一个具有三轴磁矩的磁偶极子,并考虑其航向因素,根据理论分析得出了以潜艇为中心的直角坐标系下的磁场表达式,在此基础上建立了航空磁探仪搜潜的数学模型。利用蒙特卡洛法仿真了飞机航向对磁探仪搜潜概率的影响。仿真结果表明利用磁探仪搜潜时飞机应尽量南北飞行。

  6. Test-system Design of Nozzle Solenoid Valve for the Certain Aero-engine%某型飞机发动机喷口电磁阀测试系统的设计

    Institute of Scientific and Technical Information of China (English)

    张伟; 任再青

    2015-01-01

    Based on the test requirement of hydraulic solenoid valve of exhaust nozzle exit of a certain aero-engine, the test-system of the hy-draulic solenoid valve is designed. The test-system consists of hydraulic measurement and control unit, a electronic measurement unit and a software control unit. It can be used to perform the performance parameter test of the hydraulic solenoid valve.The test-system is fulfilled the needs of fighter repair factories and worked in good condition.%根据飞机发动机喷口电磁阀的测试需求,设计了电磁阀的测试系统.该系统由液压测控单元,电子测量单元,软件控制单元组成.可以对喷口电磁阀密封性能、溢流性能、工作性能参数测量.试验结果表明:测试系统满足航修厂对喷口电磁阀的测试需求,在应用中取得良好效果.

  7. 航空无刷同步起动/发电机单相交流励磁系统研究%Research on Single-Phase AC Excitation System of Aero Brushless Synchronous Starter/Generator System

    Institute of Scientific and Technical Information of China (English)

    王铮; 刘卫国; 焦宁飞; 杨南方

    2012-01-01

    In allusion to aero brushless synchronous starter/generator system, the characteristics of the excitation system were researched under the single-phase AC excitation condition. Under the single-phase AC excitation condition, the output voltage characteristic of the magnetizing exciter was analyzed in stationary state by using the finite element analysis method. The main generator excitation characteristic was also studied, and the generator optimal excitation condition was found and verified by experiment. In rotating state, the characteristic of the main generator excitation was analyzed under the single-phase AC excitation condition and DC excitation condition respectively. By comparing the DC and AC excitation characteristic curve, the optimal speed range for AC/DC switching was obtained.%针对航空无刷同步起动/发电机,进行了单相交流励磁下励磁系统的特性研究.利用有限元仿真分析方法,对单相励磁下励磁机静止时的电压输出特性进行研究,并探讨主发电机的励磁特性,寻求主发电机最优励磁条件并通过试验进行验证;开展旋转状态下交流和直流励磁时主发电机励磁特性分析;通过对比直流励磁特性曲线与交流励磁特性曲线,得到励磁机交/直流励磁最优切换区间.

  8. Study on thermodynamic cycle parameter matching for intercooled recuperated aero-engine%间冷回热循环航空发动机参数匹配研究

    Institute of Scientific and Technical Information of China (English)

    龚昊; 王占学; 刘增文

    2012-01-01

    The intercooled and recuperated processes were incorporated into the conventional high bypass turbofan engine thermodynamic cycle. Consequently, the intercooled recuperated aero-engine (IRA) simulation model was built and an overall performance simulation program was developed. Then, analysis on choosing and matching the thermodynamic cycle parameters of IRA was conducted. The result indicates that there are some thermody- namic cycle parameters such as intercooler effectiveness, recuperator effectiveness, bypass intercooling split, pressure ratio assignment between booster and high pressure compressor, overall pressure ratio and bypass ratio, which have significant influence on IRA performance. The turbofan engine performance can be improved with the proper use of intercooling, recuperation and the optimized matching of the thermodynamic cycle parameters.%在常规大涵道比涡扇发动机热力循环基础上增加间冷过程和回热过程,发展了间冷回热循环航空发动机(IRA)的计算模型和相应的性能仿真程序.分析了采用间冷回热技术的分排大涵道比涡扇发动机的热力循环参数选择与匹配.结果表明:间冷度、回热度、外涵道间冷用气量、增压级和高压压气机压比分配、总增压比、涵道比等热力循环参数对IRA的性能有很大影响;合理应用间冷回热技术,并优化发动机热力循环参数匹配可以显著改善发动机的性能.

  9. Experiment of Kerosene/Air Pulse Detonation Engine with Aero-valve Structure%气动阀门结构煤油/空气脉冲爆震发动机试验

    Institute of Scientific and Technical Information of China (English)

    何小明; 王家骅; 张靖周

    2011-01-01

    以煤油为燃料、空气为氧化剂,采用气动阀门结构进气,组合结构障碍物强化燃烧和双半V型障碍物加强激波反射,在内径100 mm,长为1 340 mm的爆震管内进行大量的爆震试验,实现工作频率58.8 Hz协调工作.研究爆震室内主要部件在不同工作阶段的功能,并分析主要部件的工作机理,分析了煤油/空气两相可燃混气形成过程,研究煤油/空气脉冲爆震发动机爆震波特性,获得煤油/空气脉冲爆震发动机协调工作关键技术.研究结果为煤油/空气脉冲爆震发动机原理样机设计提供了理论基础.%Multi-cycle pulse detonation experiments with heated air filled and liquid kerosene fuel injected by aero-valve and accelerating combustion by combined intensifying combustion assembly are carried out in a detonation tube with 100 mm in inner diameter and 1 340 mm in length, and the pulse detonation engine can operate at a frequency up to 58-8 Hz. The function and principle of main parts in the detonation chamber are analyzed with different operation process of pulse detonation engine. The formation mechanism of two-phase combustible mixture and the detonation wave properties are investigated. The key technologies of harmony operation of kerosene/air pulse detonation engine are obtained.

  10. 模糊自整定PID的航空发动机转速控制研究%Rotating Speed Control for Aero-engine Based on Fuzzy Serf-tuning PID Controller

    Institute of Scientific and Technical Information of China (English)

    乔伯真; 缑林峰

    2013-01-01

    Due to the strong nonlinearity and time - variation of aero - engine, it is difficult for the rotating speed control system based on the method of fixed parameters PID to possess the consistent performance. In consideration of this problem, a fuzzy self - tuning PID controller was proposed. On the base of the input errors and its changing rate, a group of online self - tuning rules were built for PID parameters. And the fuzzy reasoning methods were used to calculate the new parameters in real - time. Then combining with the nonlinear real - time model of an core - engine, the rotating speed cascade control hardware system was simulated in the loop. The result indicates that the fuzzy self - tuning PID controller realizes the online tuning of parameters with a small switchover disturbance and meets the requirements of the rotate speed control in the full envelope.%航空发动机具有强非线性和强时变性的特点,使用定参数PID方法的转速控制系统的性能在全飞行包线内难以保证.针对上述问题,提出设计模糊自整定PID控制器,利用输入误差及变化率建立一组PID参数在线调整规则,运用模糊推理方法实时进行参数自整定.结合某型航空发动机核心机非线性实时模型,进行转速串级控制硬件在回路仿真.结果表明,提出的模糊自整定PID控制方法实现了控制器参数在线调整,参数切换扰动小,满足全包线内转速控制的指标要求.

  11. 间冷回热循环发动机回热器套管结构优化%Structural optimization on recuperator guide vane of intercooled recuperated aero- engine

    Institute of Scientific and Technical Information of China (English)

    周雷; 娄德仓; 郭文; 童传琛

    2016-01-01

    以减小回热器管束内流量分配不均匀度和套管质量为目的,利用Isight集成CFD建模和仿真流程,优化间冷回热循环发动机回热器套管结构尺寸,同时还分析了单个及多个套管结构对回热器流量均匀度的影响。结果表明,单套管长度为135 mm时,回热器内不均匀度最低,为0.27422;两套管结构套管长度分别为75 mm和203 mm时,不均匀度最低;三套管结构套管长度分别为23 mm、121 mm和78 mm时,不均匀度最低。前端套管对回热器不均匀度的影响最大,回热器中套管数目越多其不均匀度越大。%In order to reduce the mass flow non-uniformity and the weight of guide vane in recuperator, CFD modeling and simulation integrated by Isight was used to optimize the size of recuperator guide vane of intercooled recuperated aero-engine (IRA), and the influence of single and multiple guide vane struc⁃ture on mass flow non-uniformity was analyzed at the same time. The results show that when the length equals to 135 mm, the mass flow non-uniformity of single guide vane structure is the least; that’s the same for the double guide vane structure with 75 mm and 203 mm long and the three guide vane structure with 23 mm, 121 mm and 78 mm long. The optimization results show that the front guide vane of recupera⁃tor has most influence on mass flow non-uniformity. The more guide vanes in recuperator, the worse non-uniformity will be.

  12. What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3–UKCA and inter-model variation from AeroCom Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Kipling, Zak; Stier, Philip; Johnson, Colin E.; Mann, Graham W.; Bellouin, Nicolas; Bauer, Susanne E.; Bergman, Tommi; Chin, Mian; Diehl, Thomas; Ghan, Steven J.; Iversen, Trond; Kirkevåg, Alf; Kokkola, Harri; Liu, Xiaohong; Luo, Gan; van Noije, Twan; Pringle, Kirsty J.; von Salzen, Knut; Schulz, Michael; Seland, Øyvind; Skeie, Ragnhild B.; Takemura, Toshihiko; Tsigaridis, Kostas; Zhang, Kai

    2016-02-01

    The vertical profile of aerosol is important for its radiative effects, but weakly constrained by observations on the global scale, and highly variable among different models. To investigate the controlling factors in one particular model, we investigate the effects of individual processes in HadGEM3–UKCA and compare the resulting diversity of aerosol vertical profiles with the inter-model diversity from the AeroCom Phase II control experiment.

    In this way we show that (in this model at least) the vertical profile is controlled by a relatively small number of processes, although these vary among aerosol components and particle sizes. We also show that sufficiently coarse variations in these processes can produce a similar diversity to that among different models in terms of the global-mean profile and, to a lesser extent, the zonal-mean vertical position. However, there are features of certain models' profiles that cannot be reproduced, suggesting the influence of further structural differences between models.

    In HadGEM3–UKCA, convective transport is found to be very important in controlling the vertical profile of all aerosol components by mass. In-cloud scavenging is very important for all except mineral dust. Growth by condensation is important for sulfate and carbonaceous aerosol (along with aqueous oxidation for the former and ageing by soluble material for the latter). The vertical extent of biomass-burning emissions into the free troposphere is also important for the profile of carbonaceous aerosol. Boundary-layer mixing plays a dominant role for sea salt and mineral dust, which are emitted only from the surface. Dry deposition and below-cloud scavenging are important for the profile of mineral dust only.

    In this model, the microphysical processes of nucleation, condensation and coagulation dominate the vertical profile of the smallest particles by number (e.g. total CN > 3 nm), while the profiles of larger particles (e

  13. High Performance Magnetic Bearings for Aero Applications

    Science.gov (United States)

    Allaire, P. E.; Knospe, C. R.; Williams, R. D.; Lewis, D. W.; Barrett, L. E.; Maslen, E. H.; Humphris, R. R.

    1997-01-01

    Several previous annual reports were written and numerous papers published on the topics for this grant. That work is not repeated here in this final report. Only the work completed in the final year of the grant is presented in this final report. This final year effort concentrated on power loss measurements in magnetic bearing rotors. The effect of rotor power losses in magnetic bearings are very important for many applications. In some cases, these losses must be minimized to maximize the length of time the rotating machine can operate on a fixed energy or power supply. Examples include aircraft gas turbine engines, space devices, or energy storage flywheels. In other applications, the heating caused by the magnetic bearing must be removed. Excessive heating can be a significant problem in machines as diverse as large compressors, electric motors, textile spindles, and artificial heart pumps.

  14. The aero- and hydromechanics of keel yachts

    CERN Document Server

    Slooff, J W

    2015-01-01

    How and why does sail boat performance depend on the configuration and trim of boat and sails? This book provides the yachtsman with answers in a relatively straightforward account of the physical mechanisms of sailing. It presents an accessible overview of the fluid dynamic aspects of sailing and sailing technology, addressing both aeromechanics and hydromechanics.  Readers are provided with the basic principles of physics and general mechanics that will assist their understanding of the fluid mechanics of sailing yachts. Rich appendices cover not only in-depth, mathematical-physical treatments and derivations for those wishing to explore further, but also helpful summaries of basic mathematical notions for those wishing to refresh their knowledge.  This work explores keel yachts, specifically single-masted mono-hulls with ‘fore-and-aft’, Bermuda-rigged sails. However, much of it is applicable to other types of sailing vessels such as multi-hulls, yachts with multiple masts, windsurf boards and the li...

  15. Reflexive Aero Structures for Enhanced Survivability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) proposes to develop an advanced reflexive structure system to increase the survivability of aerostructures. This reflexive...

  16. Aero-Thermo-Dynamic Mass Analysis

    National Research Council Canada - National Science Library

    Shiba, Kota; Yoshikawa, Genki

    2016-01-01

    .... ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events...

  17. Aero-Hydroacoustics for Ships. Volume 1

    Science.gov (United States)

    1984-06-01

    Report) 10. SUPPLEMENTARY NOTES 19. KEY WORDS (Corl,t.’iu on ree a ide if necessary and Identify by block number) Aeroacoutics Lifting Surface Noise...A at Reynolds numbers near 105 by Davies, Fisher, and Barratt I1 2 1 1 7 . _. .. . and by Laurence also give 1 0.13 yl for D < v < 6D, independently...of radial location from the centerline. 117 A radial integral scale, given by Laurence , is A r 0.05 yl S where SA ; R(O,r ,0,O;y) drr r’ P ; r. . 0

  18. Reflexive Aero Structures for Enhanced Survivability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) will develop an advanced reflexive structure technology system to increase the survivability of future systems constructed of...

  19. Aero-tactile integration in speech perception

    OpenAIRE

    Gick, Bryan; Derrick, Donald

    2009-01-01

    Visual information from a speaker’s face can enhance1 or interfere with2 accurate auditory perception. This integration of information across auditory and visual streams has been observed in functional imaging studies3,4, and has typically been attributed to the frequency and robustness with which perceivers jointly encounter event-specific information from these two modalities5. Adding the tactile modality has long been considered a crucial next step in understanding multisensory integration...

  20. Aero-acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Michelsen, Jess; Sørensen, Jens Nørkær

    2002-01-01

    A numerical algorithm for acoustic noise generation is extended to 3D flows. The approach involves two parts comprising a viscous incompressible flow part and an inviscid acoustic part. In order to simulate noise generated from a wind turbine, the incompressible and acoustic equations are written...

  1. Aero-Acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Zhu, Wei Jun

    2008-01-01

    integration, the classical 4-stage Runge-Kutta scheme is applied. Non-centered high-order schemes at numerical boundaries and high-order filter schemes are also discussed due to their importance. The method was validated against a few test cases and further applied for flows around a cylinder and an airfoil...

  2. Aero-tactile integration in speech perception

    Science.gov (United States)

    Gick, Bryan; Derrick, Donald

    2013-01-01

    Visual information from a speaker’s face can enhance1 or interfere with2 accurate auditory perception. This integration of information across auditory and visual streams has been observed in functional imaging studies3,4, and has typically been attributed to the frequency and robustness with which perceivers jointly encounter event-specific information from these two modalities5. Adding the tactile modality has long been considered a crucial next step in understanding multisensory integration. However, previous studies have found an influence of tactile input on speech perception only under limited circumstances, either where perceivers were aware of the task6,7 or where they had received training to establish a cross-modal mapping8–10. Here we show that perceivers integrate naturalistic tactile information during auditory speech perception without previous training. Drawing on the observation that some speech sounds produce tiny bursts of aspiration (such as English ‘p’)11, we applied slight, inaudible air puffs on participants’ skin at one of two locations: the right hand or the neck. Syllables heard simultaneously with cutaneous air puffs were more likely to be heard as aspirated (for example, causing participants to mishear ‘b’ as ‘p’). These results demonstrate that perceivers integrate event-relevant tactile information in auditory perception in much the same way as they do visual information. PMID:19940925

  3. Aero-Acoustic Propulsion Lab (AAPL)

    Data.gov (United States)

    Federal Laboratory Consortium — This facility is an acoustically treated geodesic dome. The 130-ft-diameter dome is 65-ft high and acts as a noise barrier, protecting adjacent Glenn buildings and...

  4. Aero-Optics at Shorter Wavelengths.

    Science.gov (United States)

    1980-03-01

    heliostat 1.93 1788 60 coelostat 2.40 2161 60 Changing from a CO2 laser to an iodine laser gives a wavelength ratio of 1/8. Assuming S is fixed, the...thickness and velocity profile. When the wall is concave to the external flow, Gortler vortices may occur. Cooling or heating can alter boundary layer

  5. Aero-acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Michelsen, Jess; Sørensen, Jens Nørkær

    2002-01-01

    A numerical algorithm for acoustic noise generation is extended to 3D flows. The approach involves two parts comprising a viscous incompressible flow part and an inviscid acoustic part. In order to simulate noise generated from a wind turbine, the incompressible and acoustic equations are written...... in polar coordinates. The developed algorithm is combined with a so-called actuator-line technique in which the loading is distributed along lines representing the blade forces. Computations are carried out for the 500kW Nordtank wind turbine equipped with three LM19 blades. ©2001 The American Institute...

  6. Aero-Hydroacoustics for Ships. Volume 2

    Science.gov (United States)

    1984-06-01

    on the Ground Beneath a Turbulent Boundary Layer," N.B.S., Report 8942 (1966). 130. Dinklacker, A., M. Hessel , G.E.A. Meier and G. Schewe...was the approach used by Shioiri, Tsakonas and 179 180Jacobs, and Arnold et al. It now appears to have two shortcomings. First, a one-to-one...Tgakonas, S. and W.R. Jacobs, "Propeller Singing," Stevens Inst. of Tech., Davidson Lab Report R-1353 (1969). 180. Arnold , L. et al., "Propeller Singing

  7. 航空发动机高速电磁阀控制模式分析研究%Research on High Speed Duty Ratio Control Method of Solenoid on Aero-engine

    Institute of Scientific and Technical Information of China (English)

    王秋霞; 樊丁; 彭凯; 刘宇琦

    2013-01-01

    High speed solenoid is a key component of aero-engine electric control system. Two control methods applied in engineering are the variable frequency method and the steady frequency method. However, it is not easy to find the research on the comparison of these two methods both at home and abroad. To better understand the different effects these two methods have on the control of the system and offer some help on the choice of the control method in engineering, the model of high speed solenoid and typical mechanical—hydraulic control system was built with AMES-im. Based on this model, two comparisons have been made. One of them was between the settled frequency duty ratio (SFDR) control algorithm and the variable frequency duty ratio (VFDR) control algorithm. The other one was done according to the different frequency in the settled frequency control. The simulation shows that the VFDR has better quality than the SFDR in the response time, and they are nearly equal in other aspects. As the frequency grows, the response time slows down while the overshoot of the system decreases. As the frequency decreases, the result is completely opposite.%高速电磁阀是航空发动机实现电子控制部件,工程应用中通常采用定频与变频两种驱动方式,而应对控制效果方面进行对比研究.为比较两种方式对系统控制的影响,为相关控制模式选型提供参考,在AMESim环境下建立了电磁阀及典型航空发动机机械液压主燃油流量控制系统的数学模型,运用数字仿真方法,研究了定频变占空比及变频变占空比两种驱动控制模式对系统性能的影响,以及定频控制模式下不同频率对系统性能的影响.结果表明:变频控制方式在快速性方面优于定频控制,其它性能相当.定频控制模式下,驱动频率增加,系统响应的超调量减小但响应速度变慢;驱动频率降低,系统的响应速度变快但超调量增大.

  8. 基于实数编码量子进化算法和模态区间数学的航空发动机设计%Aero-engine Design Based on Real-coded Quantum Evolutionary Algorithm and Modal Interval Analysis

    Institute of Scientific and Technical Information of China (English)

    陈思兵; 张凯; 潘率诚; 杨冬卫

    2014-01-01

    Real-coded quantum evolutionary algorithm and Modal Interval Analysis were combined to solve dififcult problems in Modal Interval Analysis. Used real-coded quantum evolutionary algorithm to solve modal interval liner equations and inverse matrix of modal interval matrix. And then used real-coded quantum evolutionary algorithm and Modal Interval Analysis in overall performance design of aero-engine. Design method of overall performance of aero-engine based on Modal Interval Analysis wass presented , which can analysis design uncertainty. Took a certain type of turbojet engine as an example to calculate and design the results are more in line with the actual situation.%本文将实数编码量子进化算法和模态区间数学相结合用于解决模态区间数学中的某些难以求解的问题。应用量子进化算法进行了模态区间数学方程组的求解和模态区间矩阵的求逆,将量子进化算法和模态区间数学用于航空发动机的设计,给出了基于模态区间数学的航空发动机总体性能设计方法。这种设计方法能够考虑设计的不确定性。并以某型涡喷发动机为例进行计算,设计结果更符合实际情况。

  9. A finite element modeling method of aero-engine rotor without physical prototype%一种无样机的航空发动机转子有限元建模方法

    Institute of Scientific and Technical Information of China (English)

    边杰; 梅庆; 臧朝平; 杨海

    2015-01-01

    established. As the frequency error of the reference model and tested model is within 3%, the reference model can be used to update the simplified model. Finally, a correlation was analyzed and frequency response functions between the tested model and updated simplified model were com-pared. The frequency differences of them are in 2%, and matching values of modal assurance criteri-on are higher than 81%, which verified the correctness and effectiveness of the updated simplified model updated by the reference model. When this method is used to establish finite element model of a real aero-engine without physical prototype, the calculation accuracy can be improved and the a-mount of calculation can be reduced, also the period of research and development can be shortened.

  10. Implementation of the AeroRP and AeroNP in Python

    Science.gov (United States)

    2013-02-19

    world experiments conducted in ad- hoc networks with emphasis on MANET (mo- bile ad- hoc network) routing protocols is presented [11]. Our work is... hoc network environment. Also, a hybrid protocol that uses ARQ mechanism as an extension to FEC mechanism [18] in the case of loss of packets and/or... Hoc Wireless Networks,” in Proceedings of the 10th IEEE International Conference on Network Protocols, pp. 216–225, November 2002. [10] Z. Fu, P. Zerfos

  11. Aero-elastic vibration analysis based on a tower-blade coupled model of wind turbine in yaw condition%偏航状态下风力机塔架-叶片耦合结构气弹响应分析

    Institute of Scientific and Technical Information of China (English)

    柯世堂; 王同光

    2015-01-01

    A fast method to calculate aero-elastic responses of wind turbine based on a tower-blade coupled structure model was proposed.By taking the 5 MW wind turbine system designed by Nanjing University of Aeronautics and Astronautics as an example,a finite element model for investigating the wind turbine tower-blade coupled vibration was established to obtain the information of its dynamic characteristics.The harmonic superposition method and the modified blade element momentum theory were applied to calculate the aerodynamic load,considering the influence of yaw conditions.The mode superposition method was used to solve the kinetic equation of wind turbine system,the blade velocity and dynamic load were updated through iterative loop,and then the aero-elastic responses of wind turbine system were calculated.The influence of yaw angle on wind-induced responses was discussed.The research contributes a scientific basis to the wind-resistant structure design for the tower-blade system of large-scale wind turbines.%提出一套快速预测偏航状态下风力机全机结构气弹响应的分析方法。以南京航空航天大学自主研发的5MW特大型概念风力机为例,建立风力机塔架-叶片耦合模型获取模态信息;采用谐波叠加法和改进的叶素-动量理论计算气动荷载,并考虑了偏航角对诱导速度的影响;再运用模态叠加法求解风力机耦合动力学方程,通过迭代循环更新叶片速度和气动力,对风力机塔架-叶片耦合结构进行气动载荷和气弹响应计算,并通过参数分析归纳出偏航角和气动弹性对风力机全机动态响应的影响规律。研究结论可为此类特大型风力机塔架-叶片耦合结构的抗风设计提供科学依据。

  12. 2D-C/[SiC-(B-C)]复合材料在航空发动机燃烧室中的自愈合行为研究%Self-healing Behavior of 2D-C/[SiC-(B-C)] Composite in Aero-engine Combustion Chamber

    Institute of Scientific and Technical Information of China (English)

    刘光海; 成来飞; 栾新刚; 刘永胜

    2011-01-01

    采用以B-C陶瓷为基体自愈合改性组元的2D-C/[SiC-(B-C)]以及经过硅硼玻璃改性的2D-C/[SiC-(B-C)]制备浮壁瓦片,分别在1000、1200、1350℃下对其进行发动机燃烧室环境考核.对考核后的浮壁瓦片进行取样,并在室温下进行拉伸强度以及三点弯曲强度测试.结果发现:经过环境考核试样的力学性能都有不同程度的提高,拉伸强度和三点弯曲强度随着考核温度的升高而提高,其中三点弯曲强度的升高速率更快.通过SEM观察,B-C自愈合组元氧化生成的玻璃相以及改性硅硼玻璃相在考核过程中有效地封填了试样的孔隙和裂纹.最后通过力学性能测试结合SEM观察,初步分析了两种复合材料在航空发动机燃烧室中的愈合机制.%2D-C/[SiC-(B-C)] samples modified by B-C ceramic as self-healing component and boron-silicon glass phase were assessed by environmental engine experiments at 1000℃, 1200℃, 1350℃. Furthermore, tensile strength and three point bending strength of the samples were tested at room temperature after assessment. The results showed that the tensile strength and three point bending strength increased with the increase of assessment temperature, however, three point bending mechanical properties increased at a higher rate. SEM results showed that the glass phase generated by oxidization of B-C self-healing component and the boron oxide glass phase filled pores and cracks effectively. According to the experiments results, the self-healing mechanisms in aero-engine combustion chamber of such two samples were discussed.

  13. Za prezidentom v Jevrosojuz

    Index Scriptorium Estoniae

    2001-01-01

    Presidendi Euroopa Liitu astumist toetavad avaldused mõjutavad vanemat ja vaesemat elanikkonnakihti. Pealk. ajalehes Narvskaja Gazeta (2001/Nov/20): "Prezident Estonii privlekajet narod k Jevrosojuzu", lk. 2

  14. Gibraltar kurssi ei muuda / Allan Espenberg

    Index Scriptorium Estoniae

    Espenberg, Allan

    2007-01-01

    Gibraltar, Suurbritannia ja Hispaania kavandavad kolmepoolset kohtumist Gibraltari kuuluvuse arutamiseks, kuigi riigi elanikud toetavad senist valitsust juba neljandal valimisperioodil ja pooldavad senise staatuse jätkumist

  15. Za prezidentom v Jevrosojuz

    Index Scriptorium Estoniae

    2001-01-01

    Presidendi Euroopa Liitu astumist toetavad avaldused mõjutavad vanemat ja vaesemat elanikkonnakihti. Pealk. ajalehes Narvskaja Gazeta (2001/Nov/20): "Prezident Estonii privlekajet narod k Jevrosojuzu", lk. 2

  16. Receding-horizon adaptive contyrol of aero-optical wavefronts

    NARCIS (Netherlands)

    Tesch, J.; Gibson, S.; Verhaegen, M.

    2013-01-01

    A new method for adaptive prediction and correction of wavefront errors in adaptive optics (AO) is introduced. The new method is based on receding-horizon control design and an adaptive lattice filter. Experimental results presented illustrate the capability of the new adaptive controller to predict

  17. Aero-Acoustic-Structural Optimization Analysis and Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal effort is concerned with the development of a novel multidisciplinary optimization scheme and computer software for the effective design of advanced...

  18. LMI-BASED AERO-ENGINE CONTROLLER DESIGN

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The problem of analysis and synthesis of robust control is addressed in this work. The approach transferring the robust control design into Linear Matrix Inequality(LMI) is provided. The LMI standard structure of robust controller is also given and the controller is obtained through solving three LMIs. As an example, a robust control law is designed to the twin-spool turbojet engine system using the given approach. The result shows that LMI approach is feasible.

  19. Aero-Mechanical Coupling in a High-Speed Compressor

    Science.gov (United States)

    2010-02-01

    compressor flow environment (cf. Wernet (1997), Gorrell and Copenhaver (2006) and chapter 14 of Tropea et al. (2007)), primarily because of its ability to...axial compressor facility for fundamental research and flow control development. In 44th AIAA Aerospace sciences meeting and exhibit, Reno, NV. AIAA...Springer. Gorrell, S. and Copenhaver , W. (2006). Dpiv measurements of the flow field between a transonic rotor and an upstream stator. In Hall, K

  20. Predicting vibratory stresses from aero-acoustic loads

    Science.gov (United States)

    Shaw, Matthew D.

    Sonic fatigue has been a concern of jet aircraft engineers for many years. As engines become more powerful, structures become more lightly damped and complex, and materials become lighter, stiffer, and more complicated, the need to understand and predict structural response to aeroacoustic loads becomes more important. Despite decades of research, vibration in panels caused by random pressure loads, such as those found in a supersonic jet, is still difficult to predict. The work in this research improves on current prediction methods in several ways, in particular for the structural response due to wall pressures induced by supersonic turbulent flows. First, solutions are calculated using time-domain input pressure loads that include shock cells and their interaction with turbulent flow. The solutions include both mean (static) and oscillatory components. Second, the time series of stresses are required for many fatigue assessment counting algorithms. To do this, a method is developed to compute time-dependent solutions in the frequency domain. The method is first applied to a single-degree-of-freedom system. The equations of motion are derived and solved in both the frequency domain and the time domain. The pressure input is a random (broadband) signal representative of jet flow. The method is then applied to a simply-supported beam vibrating in flexure using a line of pressure inputs computed with computational fluid dynamics (CFD). A modal summation approach is used to compute structural response. The coupling between the pressure field and the structure, through the joint acceptance, is reviewed and discussed for its application to more complicated structures. Results from the new method and from a direct time domain method are compared for method verification. Because the match is good and the new frequency domain method is faster computationally, it is chosen for use in a more complicated structure. The vibration of a two-dimensional panel loaded by jet nozzle discharge flow is addressed. The surface pressures calculated at Pratt and Whitney using viscous and compressible CFD are analyzed and compared to surface pressure measurements made at the United Technologies Research Center (UTRC). A structural finite element model is constructed to represent a flexible panel also used in the UTRC setup. The mode shapes, resonance frequencies, modal loss factors, and surface pressures are input into the solution method. Displacement time series and power spectral densities are computed and compared to measurement and show good agreement. The concept of joint acceptance is further addressed for two-dimensional plates excited by supersonic jet flow. Static and alternating stresses in the panel are also computed, and the most highly stressed modes are identified. The surface pressures are further analyzed in the wavenumber domain for insight into the physics of sonic fatigue. Most of the energy in the wall pressure wavenumber-frequency spectrum at subsonic speeds is in turbulent structures near the convective wavenumber. In supersonic flow, however, the shock region dominates the spectrum at low frequencies, but convective behavior is still dominant at higher frequencies. When the forcing function wavenumber energy overlaps the modal wavenumbers, the acceptance of energy by the structure from the flow field is greatest. The wavenumber analysis suggests a means of designing structures to minimize overlap of excitation and structural wavenumber peaks to minimize vibration and sonic fatigue.

  1. Advanced materials and protective coatings in aero-engines application

    OpenAIRE

    M. Hetmańczyk; L. Swadźba; B. Mendala

    2007-01-01

    Purpose: The following article demonstrates the characteristics of the materials applied as parts of aircraft engine turbines and the stationary gas turbines. The principal technologies for manufacturing the heat resistant coatings and the erosion and corrosion resistant coatings were characterized. Sample applications for the aforementioned coatings are presented: on turbine blades, compressor blades and on parts of combustion chambers of aircraft engines.Design/methodology/approach: The nic...

  2. Performance optimization of grooved slippers for aero hydraulic pumps

    Institute of Scientific and Technical Information of China (English)

    Chen Juan; Ma Jiming; Li Jia; Fu Yongling

    2016-01-01

    A computational fluid dynamics (CFD) simulation method based on 3-D Navier–Stokes equation and Arbitrary Lagrangian–Eulerian (ALE) method is presented to analyze the grooved slip-per performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry (groove width and radius, orifice size) on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

  3. Performance optimization of grooved slippers for aero hydraulic pumps

    Directory of Open Access Journals (Sweden)

    Juan Chen

    2016-06-01

    Full Text Available A computational fluid dynamics (CFD simulation method based on 3-D Navier–Stokes equation and Arbitrary Lagrangian–Eulerian (ALE method is presented to analyze the grooved slipper performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry (groove width and radius, orifice size on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

  4. Common indoor and outdoor aero-allergens in South Africa

    African Journals Online (AJOL)

    .1 In 1971, in his survey of 67 towns in South Africa, he reported that mite numbers ... Studies from inland towns and cities at higher altitudes showed a ... coastal areas, with some of the strongest reactions .... rhinitis population in the Free State.

  5. Combined Aero and Underhood Thermal Analysis for Heavy Duty Trucks

    Energy Technology Data Exchange (ETDEWEB)

    Vegendla, Prasad [Argonne National Lab. (ANL), Argonne, IL (United States); Sofu, Tanju [Argonne National Lab. (ANL), Argonne, IL (United States); Saha, Rohit [Cummins Inc., Columbus, IN (United States); Madurai Kumar, Mahesh [Cummins Inc., Columbus, IN (United States); Hwang, L. K [Cummins Inc., Columbus, IN (United States)

    2017-01-31

    Aerodynamic analysis of the medium-duty delivery truck was performed to achieve vehicle design optimization. Three dimensional CFD simulations were carried out for several improved designs, with a detailed external component analysis of wheel covers, side skirts, roof fairings, and rounded trailer corners. The overall averaged aerodynamics drag reduction through the design modifications were shown up to 22.3% through aerodynamic considerations alone, which is equivalent to 11.16% fuel savings. The main identified fuel efficiencies were based on second generation devices, including wheel covers, side skirts, roof fairings, and rounded trailer corners. The important findings of this work were; (i) the optimum curvature radius of the rounded trailer edges found to be 125 mm, with an arc length of 196.3 mm, (ii) aerodynamic drag reduction increases with dropping clearance of side skirts between wheels and ground, and (iii) aerodynamic drag reduction increases with an extension of front bumper towards the ground.

  6. Technology challenges for the National Aero-Space Plane

    Science.gov (United States)

    Piland, William M.

    1987-01-01

    The National Aerospace Plane (NASP) will require an exceptionally high degree of integration between propulsion and aerodynamic configuration, in order to achieve the requisite specific impulse and low structural weight. This is to be achieved through the use of forebody shock compression and afterbody exhaust expansion. Attention is presently given to the materials and structural concepts required for the realization of these NASP airframe functions, in view of the exceptionally high aerothermodynamic loads that will be experienced at hypersonic speeds. Active cooling will have to be used in certain critical airframe and propulsion components. CFD characterizations of these processes must be carefully developed and fully validated.

  7. Aero-Optical Investigation of a Pod Directed Energy System

    Science.gov (United States)

    2010-02-28

    VTT 2 2 −= (5) ( ) ( )zyxKzyxn GD ,,1,, ρ−= (6) KGD is the Gladstone-Dale constant for a 1 μm wavelength in air, KGD = 2.25 x 10-3 kg/m3...generated vortex wakes of subsonic transport air,” Progress in Aerospace Sciences (1999) 35: 507-660. [11] Zang, H.J., Zhou, Y., Whitelaw, J.H., “Near

  8. Aero Engine Fault Diagnosis Using an Optimized Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Xinyi Yang

    2016-01-01

    Full Text Available A new extreme learning machine optimized by quantum-behaved particle swarm optimization (QPSO is developed in this paper. It uses QPSO to select optimal network parameters including the number of hidden layer neurons according to both the root mean square error on validation data set and the norm of output weights. The proposed Q-ELM was applied to real-world classification applications and a gas turbine fan engine diagnostic problem and was compared with two other optimized ELM methods and original ELM, SVM, and BP method. Results show that the proposed Q-ELM is a more reliable and suitable method than conventional neural network and other ELM methods for the defect diagnosis of the gas turbine engine.

  9. Aero-Effected Flight Control Using Distributed Active Bleed

    Science.gov (United States)

    2012-01-30

    x/c ≤ 0.28. A better scheme is to use the actual net pressure distribution near the leading edge of a Clark-Y airfoil with no bleed as a measure...due to continuous, high-frequency actuation, 10° <  < 22°. work (e.g. Carta , 1967, Carta and Carlson, 1973) quantifies the extent of these enclosures...Layer Instability,” AIAA J, 39, 597-604, 2001. Carta , F. O., “An Analysis of the Stall Flutter Instability of Helicopter Rotor Blades,” Journal of the

  10. Aero-Elastic Optimization of a 10 MW Wind Turbine

    DEFF Research Database (Denmark)

    Zahle, Frederik; Tibaldi, Carlo; Verelst, David Robert;

    2015-01-01

    This article describes a multi-disciplinary optimization and analysis tool for wind turbines that is based on the open-source framework OpenMDAO. Interfaces to several simulation codes have been implemented which allows for a wide variety of problem formulations and combinations of models....... In this article concurrent aeroelastic optimization of a 10 MW wind turbine rotor is carried out with respect to material distribution distribution and planform. The optimizations achieve up to 13% mass reduction while maintaining the same power production compared to the baseline DTU 10MW RWT....

  11. An Aero-Acoustic Tool for Terminal Area Operations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this highly interconnected world, transportation systems must feature increased flexibility and shorter door-to-door trip times to be successful. Shorter...

  12. Control of Boundary Layers for Aero-optical Applications

    Science.gov (United States)

    2015-06-23

    fluctuating density cause initially planar optical wavefronts passing through them to be distorted ( Gladstone & Dale, 1863; Liepmann, 1952; Tatarski...8217),,( tyxOPLtyxOPLtyxOPD dytzyxKtyxOPL b a GD −= = ∫ ρ (1.1) where KGD is the Gladstone -Dale constant, the integration is...Ross, 2009; Porter, et al. 2013) Sutton ( 1969 ) introduced the most widely cited theoretical formulation for calculating the effect of turbulent

  13. Atmospheric Turbulence Modeling for Aero Vehicles: Fractional Order Fits

    Science.gov (United States)

    Kopasakis, George

    2015-01-01

    Atmospheric turbulence models are necessary for the design of both inlet/engine and flight controls, as well as for studying coupling between the propulsion and the vehicle structural dynamics for supersonic vehicles. Models based on the Kolmogorov spectrum have been previously utilized to model atmospheric turbulence. In this paper, a more accurate model is developed in its representative fractional order form, typical of atmospheric disturbances. This is accomplished by first scaling the Kolmogorov spectral to convert them into finite energy von Karman forms and then by deriving an explicit fractional circuit-filter type analog for this model. This circuit model is utilized to develop a generalized formulation in frequency domain to approximate the fractional order with the products of first order transfer functions, which enables accurate time domain simulations. The objective of this work is as follows. Given the parameters describing the conditions of atmospheric disturbances, and utilizing the derived formulations, directly compute the transfer function poles and zeros describing these disturbances for acoustic velocity, temperature, pressure, and density. Time domain simulations of representative atmospheric turbulence can then be developed by utilizing these computed transfer functions together with the disturbance frequencies of interest.

  14. Multidisciplinary Aerospace Systems Optimization: Computational AeroSciences (CAS) Project

    Science.gov (United States)

    Kodiyalam, S.; Sobieski, Jaroslaw S. (Technical Monitor)

    2001-01-01

    The report describes a method for performing optimization of a system whose analysis is so expensive that it is impractical to let the optimization code invoke it directly because excessive computational cost and elapsed time might result. In such situation it is imperative to have user control the number of times the analysis is invoked. The reported method achieves that by two techniques in the Design of Experiment category: a uniform dispersal of the trial design points over a n-dimensional hypersphere and a response surface fitting, and the technique of krigging. Analyses of all the trial designs whose number may be set by the user are performed before activation of the optimization code and the results are stored as a data base. That code is then executed and referred to the above data base. Two applications, one of the airborne laser system, and one of an aircraft optimization illustrate the method application.

  15. Aero-disaster in Port Harcourt, Nigeria: A case study

    African Journals Online (AJOL)

    include ages, sex, pattern of injuries and death as well as problems associated with identification ... only 16 (16.5%), severe head injury alone 11 (11.3%) and ruptured viscous 2 (2.1%) were the causes of death at .... 120 (9.5%) people, while 2006 had two disasters that ... implanted bombs, fear and panic during hijacking,.

  16. 76 FR 77108 - Airworthiness Directives; International Aero Engines Turbofan Engines

    Science.gov (United States)

    2011-12-12

    ... EGT margin abrupt trend shifts. We disagree. EGT margin allows the operator to use more of the... Changes One commenter, TAM Airlines, asked for guidance on how to manage engine position changes after... Exhaust gas seal segments hours- seal segments cycles- temperature margin Engine model since-new or since...

  17. Airborne Aero-Optics Laboratory - Transonic (AAOL-T)

    Science.gov (United States)

    2016-10-03

    The normalized spatial distributions of OPDRMS are shown in Figure 8. Both the M = 0.7 wavefronts, left and M = 0.8 wavefronts, right show an increase...IN 465565602 10/17/2016 Final Report DISTRIBUTION A: Distribution approved for public release. Air Force Research Laboratory AF Office Of...Randolph Arlington, VA 22203 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION /AVAILABILITY STATEMENT DISTRIBUTION

  18. Process Improvement Through Tool Integration in Aero-Mechanical Design

    Science.gov (United States)

    Briggs, Clark

    2010-01-01

    Emerging capabilities in commercial design tools promise to significantly improve the multi-disciplinary and inter-disciplinary design and analysis coverage for aerospace mechanical engineers. This paper explores the analysis process for two example problems of a wing and flap mechanical drive system and an aircraft landing gear door panel. The examples begin with the design solid models and include various analysis disciplines such as structural stress and aerodynamic loads. Analytical methods include CFD, multi-body dynamics with flexible bodies and structural analysis. Elements of analysis data management, data visualization and collaboration are also included.

  19. Organically Modified Aero-Sol Gel Silica for Elastomer Reinforcement

    Science.gov (United States)

    Pratsinis, S. E.; Kohls, D. J.; Beaucage, G.

    2000-03-01

    We have developed facilities to produce organically functionalized silicas using a novel, room-temperature, aerosol, chemical reactor (ASG reactor). This reactor can produce exceedingly high surface area nano-structured materials (up to 800 m2/g) with tuned interfacial chemistries. This poster will present our results on dynamic mechanical properties of elastomer compounds with ASG-organically modified silicas and comparison with conventional carbon black, conventional precipated and fumed silica as well as blends of the conventional materials. The mass-fractal structure as determined by SAXS and SALS, as well as conventional gas and DBP absorption measurements and microscopy will be presented. Hyeon-Lee, J.; Beaucage, G.; Pratsinis, S. E. (1997) Chem. of Mat. 9, 2400. Hyeon-Lee, J.; Beaucage, G.; Pratsinis, S. E.; Vemury, S. (1998) Langmuir 5751.

  20. Process fluids of aero-hydraulic systems and their properties

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2014-01-01

    Full Text Available The article considers process fluids, which are presently applied to aviation hydraulic systems in domestic and world practice. Aviation practice deals with rather wide list of fluids. Based on the technical specification a designer makes the choice of specific fluid for the specific aircraft. Process fluids have to possess the specified properties presented in the article, namely: lubricating properties; stability of physical and chemical characteristics at operation and storage; lowtemperature properties; acceptable congelation temperature; compatibility with materials of units and components of hydraulic systems; heat conductivity; high rigidity; minimum low coefficient of volume expansion; fire-explosion safety; low density. They should also have good dielectric properties, be good to resist to destruction of molecules, have good anticorrosion and antierosion properties, as well as not create conditions for emerging electro-kinetic erosion of spooltype and other precision devices, and a number of other properties.The article presents materials on the oil-based process fluids with + (200-320 °C boiling temperature, gelled by a polymer of vinyl butyl ether, with aging inhibitor and dye for hydraulic systems of the subsonic and transonic aircraft which are combustible, with a temperature interval of use from — 60oС до +125oС. It also describes materials on process fluids, which are based on the mix of polydialkylsiloxane oligomers with organic diester aging inhibitors, and wear-resistant additive to be applied to the hydraulic systems of supersonic aircrafts using a fluid within the temperature interval from - 6О oС to +175oС for a long duration. The fire-explosion safety process fluids representing a mix of phosphoric esters with additives to improve viscous, anti-oxidizing, anticorrosive and anti-erosive properties are considered as well. They are used within the temperature range from - 60оС to +125оС with overheats up to +150оС.The article shows experimentally attained properties of process fluids for the aviation hydraulic systems. These properties are essential in design engineering and operation of aircraft equipment.

  1. Designing aircraft in Italy; internship at Piaggio Aero Industries

    OpenAIRE

    Coosemans, J.

    2013-01-01

    From October 2012 to January 2013, I went to the south of Italy to do my internship at Piaggio, the company famous for manufacturing the P.180 Avanti business aircraft. The office where I was located was in Pozzuoli, a town just outside the city of Naples, in the shadow of Mount Vesuvius.

  2. Aero dynamical and mechanical behaviour of the Savonius rotor

    Energy Technology Data Exchange (ETDEWEB)

    Aouachria, Z. [Batna Univ., (Algeria). Applied Energetic Physics Laboratory

    2009-07-01

    Although the Savonius wind turbine is not as efficient as the traditional Darrieus wind turbine, its rotor design has many advantages such as simple construction; acceptance of wind from all directions; high starting torque; operation at relatively low speed; and easy adaptation to urban sites. These advantages may outweigh its low efficiency and make it suitable for small-scale power requirements such as pumping and rural electrification. This paper presented a study of the aerodynamic behaviour of a Savonius rotor, based on blade pressure measurements. A two-dimensional analysis method was used to determine the aerodynamic strengths, which leads to the Magnus effect and the generation of the vibrations on the rotor. The study explained the vibratory behaviour of the rotor and proposed an antivibration system to protect the machine. 14 refs., 1 tab., 9 figs.

  3. Reconstruction and calibration on aero-optical wavefront ab erration based on background oriented schlieren based wavefront sensing%基于背景纹影波前传感技术的气动光学波前重构与校正∗

    Institute of Scientific and Technical Information of China (English)

    张天天; 易仕和; 朱杨柱; 何霖

    2015-01-01

    Background oriented schlieren based wavefront sensing (BOS-WS) is a new experimental technique for measuring the two-dimensional distribution of optical wavefronts and the optical path differences (OPDs) induced by the flow-field density variations. Background oriented schlieren (BOS) is traditionally used to test the flow-field density distribution, which restricts the obtaining of useful information since the obtained density information is integrated over the optical path. The OPD is very important for predicting the optical distortion when light travels through the flow field and it is tested by BOS-WS. In order to obtain the optical distortion generated by aero-optic effect, and restore the original image from the distortion known information so as to explore a new kind of supersonic imaging guidance method, theory analysis, numerical simulation and experimental methods are used based on BOS-WS. Through theoretical analysis, the wavefront measurement method based on BOS is verified and the calculation methods of using wavefront information known to predict distortion displacement field and using known displacement field to reconstruct wavefront are explored. By numerical simulation, the error sizes and the result rationalities of one stepped integral algorithm and Southwell method on the wavefront reconstruction are compared, and through the error analysis it is proved that the Southwell method is more accurate and reasonable. By a wavefront aberration experiment carried out in the flow field above the candle flame and a lens perturbation experiment, the methods of using OPD known to reconstruct distorted displacement field and correcting image distortion by the field are creatively explored. The verification experiments show the effectiveness of the correction method.%背景纹影波前传感(background oriented schlieren based wavefront sensing, BOS-WS)是利用背景纹影技术测量光学波前二维分布的新型实验手段,可定量测量光线通过

  4. Riigi eelarvepoliitika peab olema neutraalne / Joaquin Almunia ; interv. Piret Reiljan

    Index Scriptorium Estoniae

    Almunia, Joaquin, 1948-

    2008-01-01

    Euroopa Komisjoni rahandusvoliniku Joaquin Almunia sõnul peaks Eesti vältima järeleandmisi eelarvepoliitikas, samuti tuleks prioriteediks seada investeeringud, mis toetavad majanduskasvu ning kasutada ära maksimaalselt Euroopa Liidu struktuurifonde

  5. Pool Onistarist kuulub kütusefirma omanikele / Sirje Niitra

    Index Scriptorium Estoniae

    Niitra, Sirje, 1948-

    2001-01-01

    Alkoholikontserni Onistar kiiret tõusu Eesti alkoholiturul toetavad Vene rahvusest ärimeestele kuuluvate kütusefirmade Infast Oil ja Saurix Petroleum omanikud, kellele kuulub pool Eesti viinaturu liidri aktsiatest

  6. Juhtumikorraldus - see on võimalus võimaluste seas / Annely Tikerpuu-Kattel

    Index Scriptorium Estoniae

    Tikerpuu-Kattel, Annely

    2005-01-01

    Juhtumikorralduse abil seotakse kliendiga teda kõige enam toetavad personaalsed ja kogukonna ressursid, pakkudes kliendile vajalikku integreeritud ja individuaalset abi, eesmärgiga vältida sotsiaalsete probleemide süvenemist

  7. Internetipõhised virtuaal- ja kauglaborid tuuakse loodusainete õpetajateni / Virge Tamme

    Index Scriptorium Estoniae

    Tamme, Virge

    2015-01-01

    TÜ haridusuuenduskeskuses oli 16. märtsil uurimisõpet toetava rahvusvahelise projekti Go-Lab töökoosolek. Projektimeeskond soovib aastaks 2016 avada ligi sada kaugjuhitavat teadus- ja virtuaallaborit, mis toetavad loodusainete õppimist ja õpetamist

  8. Riigi eelarvepoliitika peab olema neutraalne / Joaquin Almunia ; interv. Piret Reiljan

    Index Scriptorium Estoniae

    Almunia, Joaquin, 1948-

    2008-01-01

    Euroopa Komisjoni rahandusvoliniku Joaquin Almunia sõnul peaks Eesti vältima järeleandmisi eelarvepoliitikas, samuti tuleks prioriteediks seada investeeringud, mis toetavad majanduskasvu ning kasutada ära maksimaalselt Euroopa Liidu struktuurifonde

  9. Küttimine võib septembris peatuda. Maaomanikud vs. jahimehed / Ain Alvela ; kommenteerinud Heiki Hepner, Val Rajasaar

    Index Scriptorium Estoniae

    Alvela, Ain, 1967-

    2011-01-01

    Maksumaksjad ja maaomanikud toetavad Eesti jahindust sisuliselt viie miljoni euroga aastas, kuigi keskkonnaspetsialistide hinnangul võiks asi olla vastupidi. Kehtiv jahiseadus ei aita kaasa metsa väärtuse parandamisele. Tabelid

  10. Tony Blairi pikk hüvastijätt / Tiina Tamman

    Index Scriptorium Estoniae

    Tamman, Tiina, 1948-

    2006-01-01

    Tony Blairi teade, et Manchesteris algav Suurbritannia leiboristide aastakonverents jääb talle peaministrina viimaseks, on põhjustanud erakonnas pahameele. Mitmed parlamendiliikmed toetavad rahandusminister Gordon Browni valitsusjuhiks saamist, kuid soovitakse ka juhi valimiste korraldamist

  11. Internetipõhised virtuaal- ja kauglaborid tuuakse loodusainete õpetajateni / Virge Tamme

    Index Scriptorium Estoniae

    Tamme, Virge

    2015-01-01

    TÜ haridusuuenduskeskuses oli 16. märtsil uurimisõpet toetava rahvusvahelise projekti Go-Lab töökoosolek. Projektimeeskond soovib aastaks 2016 avada ligi sada kaugjuhitavat teadus- ja virtuaallaborit, mis toetavad loodusainete õppimist ja õpetamist

  12. Tony Blairi pikk hüvastijätt / Tiina Tamman

    Index Scriptorium Estoniae

    Tamman, Tiina, 1948-

    2006-01-01

    Tony Blairi teade, et Manchesteris algav Suurbritannia leiboristide aastakonverents jääb talle peaministrina viimaseks, on põhjustanud erakonnas pahameele. Mitmed parlamendiliikmed toetavad rahandusminister Gordon Browni valitsusjuhiks saamist, kuid soovitakse ka juhi valimiste korraldamist

  13. Pool Onistarist kuulub kütusefirma omanikele / Sirje Niitra

    Index Scriptorium Estoniae

    Niitra, Sirje, 1948-

    2001-01-01

    Alkoholikontserni Onistar kiiret tõusu Eesti alkoholiturul toetavad Vene rahvusest ärimeestele kuuluvate kütusefirmade Infast Oil ja Saurix Petroleum omanikud, kellele kuulub pool Eesti viinaturu liidri aktsiatest

  14. Vastased üritavad koos Haloneni lüüa / Erkki Bahovski

    Index Scriptorium Estoniae

    Bahovski, Erkki, 1970-

    2006-01-01

    Soome presidendivalimistel teise vooru mitte pääsenud Koonderakonna kandidaat Matti Vanhanen, Rootsi rahvapartei kandidaat Henrik Lax ja kristlike demokraatide kandidaat Bjarne Kallis toetavad teise vooru pääsenud Koonderakonna kandidaati Sauli Niinistöd

  15. Euroopa Liidul aktiivsem välispoliitika / Marianne Mikko

    Index Scriptorium Estoniae

    Mikko, Marianne, 1961-

    2005-01-01

    Euroopa Parlamendi saadik Marianne Mikko koos Marek Siwieciga esitasid ühisavalduse, kus toetavad Moldova ja Ukraina presidentide taotlust, et Euroopa Liit asuks ühtse julgeoleku- ja kaitsepoliitika võimalusi kasutades kontrollima Transnistria piiri

  16. USA ärgitab Saddami eksiili saatma / Sten A Hankewitz

    Index Scriptorium Estoniae

    Hankewitz, Sten A., 1979-

    2003-01-01

    USA kaitseminister Donald Rumsfeld, välisminister Colin Powell ja riikliku julgeoleku nõunik Condoleezza Rice toetavad ideed saata Iraagi president Saddam Hussein eksiili. Iraagi erisaadik lükkas selle võimaluse tagasi

  17. Siseriiklikud programmid võrdsete võimaluste loomiseks / Jaan Õunapuu

    Index Scriptorium Estoniae

    Õunapuu, Jaan, 1958-

    2006-01-01

    Ilmunud ka: Peipsi Rannik = Tshudskoje Poberezhje nr. 12 lk. 6, Za narod! 6. jaan. nr. 1 2007 lk. 2. Regionaalminister Jaan Õunapuu riigieelarvest rahastatud programmidest, mis toetavad piirkondade tasakaalustatud arengut

  18. Noored ootavad revolutsiooni / Silver Meikar

    Index Scriptorium Estoniae

    Meikar, Silver, 1978-

    2006-01-01

    Valgevenes on noored tulnud tänavale, et protestida presidendivalimiste tulemuste vastu. Vt. samas: Venemaa võimud toetavad avalikult Valgevene presidenti Aleksandr Lukashenkat; Lukashenka ülisuur võit

  19. Baltics support Kosovo independence / Talis Saule Archdeacon

    Index Scriptorium Estoniae

    Archdeacon, Talis Saule

    2008-01-01

    Balti riigid teatasid päev pärast Kosovo iseseisvuse väljakuulutamist, et toetavad riigi iseseisvust. Eriarvamusi pretsedendi suhtes on venelaste esindajate hulgas ning Euroopa riikide vahel. Baltimaade liidrite põhjendused

  20. Siseriiklikud programmid võrdsete võimaluste loomiseks / Jaan Õunapuu

    Index Scriptorium Estoniae

    Õunapuu, Jaan, 1958-

    2006-01-01

    Ilmunud ka: Peipsi Rannik = Tshudskoje Poberezhje nr. 12 lk. 6, Za narod! 6. jaan. nr. 1 2007 lk. 2. Regionaalminister Jaan Õunapuu riigieelarvest rahastatud programmidest, mis toetavad piirkondade tasakaalustatud arengut

  1. USA ärgitab Saddami eksiili saatma / Sten A Hankewitz

    Index Scriptorium Estoniae

    Hankewitz, Sten A., 1979-

    2003-01-01

    USA kaitseminister Donald Rumsfeld, välisminister Colin Powell ja riikliku julgeoleku nõunik Condoleezza Rice toetavad ideed saata Iraagi president Saddam Hussein eksiili. Iraagi erisaadik lükkas selle võimaluse tagasi

  2. Baltics support Kosovo independence / Talis Saule Archdeacon

    Index Scriptorium Estoniae

    Archdeacon, Talis Saule

    2008-01-01

    Balti riigid teatasid päev pärast Kosovo iseseisvuse väljakuulutamist, et toetavad riigi iseseisvust. Eriarvamusi pretsedendi suhtes on venelaste esindajate hulgas ning Euroopa riikide vahel. Baltimaade liidrite põhjendused

  3. 76 FR 60396 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Airplanes

    Science.gov (United States)

    2011-09-29

    ... Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety..., certificated in any category. Subject (d) Air Transport Association of America (ATA) Code 52: Doors. Reason (e... the door handle for proper tightness and correct as necessary after applying a thread locker...

  4. 76 FR 77369 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Airplanes

    Science.gov (United States)

    2011-12-13

    ... Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety... Transport Association of America (ATA) Code 52: Doors. (e) Reason This AD was prompted by the baggage door... tightness and correct as necessary after applying a thread locker following Part D of the...

  5. System-Level Development of Fault-Tolerant Distributed Aero-Engine Control Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's vision for an "intelligent engine" will be realized with the development of a truly distributed control system and reliable smart transducer node components;...

  6. Confronting AeroCom models with particle size distribution data from surface in situ stations

    Science.gov (United States)

    Platt, Stephen; Fiebig, Markus; Mann, Graham; Schulz, Michael

    2016-04-01

    The size distribution is the most important property for describing any interaction of an aerosol particle population with its surroundings. In first order, it determines both, the aerosol optical properties quantifying the direct aerosol climate effect, and the fraction of aerosol particles acting as cloud condensation nuclei quantifying the indirect aerosol climate effect. Aerosol schemes of modern climate models resolve the aerosol particle size distribution (APSD) explicitly. In improving the skill of climate models, it is therefore highly useful to confront these models with precision APSD data observed at surface stations. Corresponding previous work focussed on comparing size integrated, seasonal particle concentrations at selected sites with ensemble model averages to assess overall model skill. Building on this work, this project intends to refine the approach by comparing median particle size and integral concentration of fitted modal size distributions. It will also look at skill differences between models in order to find reasons for matches and discrepancies. The presentation will outline the project, and will elaborate on input requested from modelling groups to participate in the exercise.

  7. Applications Study of Aero-Maneuvering Orbit-to-Orbit Shuttle (AMOOS), Executive Summary

    Science.gov (United States)

    White, J.

    1976-01-01

    Preliminary designs and the supporting analysis for both the Aeromaneuvering Orbit-to-Orbit Shuttle (AMOOS) and the Aeromaneuvering Recovery System (AMRS) are presented. The AMOOS design is shown to yield from twice to almost three times the high energy, round-trip payloads as a purely propulsive vehicle of the same weight. Typically AMOOS can perform a crew rotation mission to equatorial geosynchronous orbit in one space shuttle launch. The flight test program analysis modeled parameters such as maximum dynamic pressure, heating rates, guidance, stability and recovery. Two model flight schedules were developed, one consisting of four flights and the other of two flights. The former is considered a very low risk, high information return program whereas the latter is a minimal cost program consistent with reasonable data returns and chance of success. The AMOOS and AMRS guidance scheme developed using linear regulator theory proved a precise and accurate guidance scheme. Both it and a classical linear system's based scheme were evaluated using 65 simulated trajectories in which the position in the entry corridor and the atmospheric density were varied randomly.

  8. Theoretical investigaion of the performance of alternative aviation fuels in an aero-enginve combustion chamber

    OpenAIRE

    2009-01-01

    When considering alternative fuels for aviation, factors such as the overall efficiency of the combustion process and the levels of emissions emitted to the atmosphere, need to be critically evaluated. The physical and chemical properties of a fuel influence the combustion efficiency and emissions and therefore need to be considered. The energy content of a biofuel, which is influenced negatively by the presence of oxygen in the molecular structure (i.e. oxygenated chemical compounds), is rel...

  9. 78 FR 36691 - Airworthiness Directives; Piaggio Aero Industries S.p.A Airplanes

    Science.gov (United States)

    2013-06-19

    ... that the cracks were initiated by an unforeseen friction in the MLG wheel lever sub-assembly. This... follows: Authority: 49 U.S.C. 106(g), 40113, 44701. Sec. 39.13 0 2. The FAA amends Sec. 39.13 by...

  10. Aero particles characterization emitted by mobile sources;Caracterizacion de aeroparticulas emitidas por fuentes moviles

    Energy Technology Data Exchange (ETDEWEB)

    Rojas V, A.; Romero G, E. T.; Lopez G, H., E-mail: elizabeth.romero@inin.gob.m [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2009-07-01

    In our country, the mobile sources that conform most of the emissions at the atmosphere, are concentrated on the urban areas. For the present work, samples coming from the escapes of terrestrial transport were obtained, such as: passenger buses, load transport and particular vehicles of the Metropolitan area of the Toluca valley. The material was analyzed by means of scanning electron microscopy of low vacuum and X-ray diffraction. The objective was to characterize the emitted particles by mobile sources, morphological and chemically to know the structure, size and elements that compose them. (Author)

  11. Research on Aero-Thermodynamic Distortion Induced Structural Dynamic Response of Multi-Stage Compressor Blading.

    Science.gov (United States)

    1984-06-01

    8217 ." :’ ;’:::::. ====================================:: : " :.; :- ..’./.’ " """ ""..’’: : " ’. ’’. -. - ..: " ’] -’: ".."-".:"’. -" . . . .’.- .."... . . "".".".’.-.. . . . .. , Stlg30. Mach.• 6 .. - 2500- Ph oseO 8000- S • 30 C/S.*OO Phase

  12. Aero-elastic Stability Analysis for Large-Scale Wind Turbines

    NARCIS (Netherlands)

    Meng, F.

    2011-01-01

    Nowadays, many modern countries are relying heavily on non-renewable resources. One common example of non-renewable resources is fossil fuel. Non-renewable resources are finite resources that will eventually dwindle, becoming too expensive or too environmentally damaging to retrieve. In contrast, ren

  13. Performance of a Supercritical CO2 Bottoming Cycle for Aero Applications

    National Research Council Canada - National Science Library

    Florian Jacob; Andrew Martin Rolt; Joshua Marius Sebastiampillai; Vishal Sethi; Mathieu Belmonte; Pedro Cobas

    2017-01-01

    .... This could provide additional shaft power. Supercritical carbon dioxide closed-circuit power cycles are currently being investigated primarily for stationary power applications, but their high power density and efficiency, even for modest...

  14. Common Aero Vehicle Autonomous Reentry Trajectory Optimization Satisfying Waypoint and No-Fly Zone Constraints

    Science.gov (United States)

    2007-09-01

    Guidance, Control, and Dynamics, 21(2):193–207, March-April 1998. 7. Betts, John T. “A Direct Approach to Solving Optimal Control Problems ,” CSE in...Paul. “Jacobi Pseudospectral Method for Solving Optimal Control Problems ,” Journal of Guidance, Control, and Dynamics, 27(2):293–297, 2004. 117

  15. Impulse Based Substructuring for Coupling Offshore Structures and Wind Turbines in Aero-Elastic Simulations

    NARCIS (Netherlands)

    Van der Valk, P.L.C.; Rixen, D.J.

    2012-01-01

    In order to achieve the goal of 20% renewable energy in 2020, as set by the European Union, large offshore wind farms are either under construction or in development through-out Europe. As many of the "easy" locations are already under development, offshore wind farms are moving further offshore int

  16. Impulse Based Substructuring for Coupling Offshore Structures and Wind Turbines in Aero-Elastic Simulations

    NARCIS (Netherlands)

    Van der Valk, P.L.C.; Rixen, D.J.

    2012-01-01

    In order to achieve the goal of 20% renewable energy in 2020, as set by the European Union, large offshore wind farms are either under construction or in development through-out Europe. As many of the "easy" locations are already under development, offshore wind farms are moving further offshore

  17. Aero-elastic Stability Analysis for Large-Scale Wind Turbines

    NARCIS (Netherlands)

    Meng, F.

    2011-01-01

    Nowadays, many modern countries are relying heavily on non-renewable resources. One common example of non-renewable resources is fossil fuel. Non-renewable resources are finite resources that will eventually dwindle, becoming too expensive or too environmentally damaging to retrieve. In contrast,

  18. Variable-fidelity and reduced-order models for aero data for loads predictions

    DEFF Research Database (Denmark)

    Goertz, Stefan; Zimmermann, Ralf; Han, Zhong Hua

    2013-01-01

    This paper summarizes recent progress in developing metamodels for efficiently predicting the aerodynamic loads acting on industrial aircraft configurations. We introduce a physics-based approach to reduced-order modeling based on proper orthogonal decomposition of snapshots of the full-order CFD...

  19. An integrated aerodynamic/propulsion study for generic aero-space planes based on waverider concepts

    Science.gov (United States)

    Emanuel, G.; Rasmussen, M. L.

    1991-01-01

    Research efforts related to the development of a unified aerospace plane analysis based on waverider technology are summarized. Viscous effects on the forebodies of cone-derived waverider configurations were studied. A simple means for determining the average skin friction coefficient of laminar boundary layers was established. This was incorporated into a computer program that provides lift and drag coefficients and lift/drag ratio for on-design waveriders when the temperature and Reynolds number based on length are specified. An effort was made to carry out parabolized Navier-Stokes (PNS) calculations for cone-derived waveriders. When the viscous terms were turned off (in the Euler mode) computations for elliptic cone-derived waveriders could be carried out for a wide range of on-design and off-design situations. Work related to waveriders derived from power law shocks is described in some detail.

  20. Numerical Computation of the Chemically Reacting Flow around the National Aero-Space Plane

    Science.gov (United States)

    Tannehill, J. C.

    1999-01-01

    This final report summarizes the research accomplished. The research performed during the grant period can be divided into the following major areas: (1) Computation of chemically reacting Supersonic combustion ramjet (scramjet) flowfields. (2) Application of a two-equation turbulence model to supersonic combustion flowfields. (3) Computation of the integrated aerodynamic and propulsive flowfields of a generic hypersonic space plane. (4) Computation of hypersonic flows with finite-catalytic walls. (5) Development of an upwind Parabolized Navier-Stokes (PNS) code for thermo-chemical nonequilibrium flows.

  1. The influence of turbulence on the aero-elastic instability of wind turbines

    DEFF Research Database (Denmark)

    Zhang, Zili; Nielsen, Søren R.K.

    2014-01-01

    aerodynamic damping. A 13-degree-of-freedom (13-DOF) wind turbine model is developed using Euler-Lagrange equations, which includes the couplings of the tower-blade-drivetrain vibration, the quasi-static aeroelasticity and a collective pitch controller. Numerical simulations are carried out using data...

  2. A Preliminary to War: The 1st Aero Squadron and the Mexican Punitive Expedition of 1916

    Science.gov (United States)

    2003-01-01

    some leaders, like Emiliano Zapata , and too liberal for others, like Pascual Orozco, Jr. Bloody fighting soon broke out across Mexico, and Madero...turned for support to Gen. Victoriano Huerta, a hard-drinking but competent soldier. Huerta crushed Orozco and kept Zapata at bay, but he had as little...Meanwhile, the state of Morelos provided a base for Zapata , the unconquered hero of the peon. The Constitutionalists forced Huerta into exile in mid

  3. MINIVER: Miniature version of real/ideal gas aero-heating and ablation computer program

    Science.gov (United States)

    Hendler, D. R.

    1976-01-01

    Computer code is used to determine heat transfer multiplication factors, special flow field simulation techniques, different heat transfer methods, different transition criteria, crossflow simulation, and more efficient thin skin thickness optimization procedure.

  4. 2007 Aero-Metric Inc. Topographic LiDAR: Valdez, Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project was completed under USGS Contract No. 07CRCN0002, Task Order No. 070020009. This delivery contains point cloud data in LAS 1.1 format, classified in the...

  5. Comparison of Aero-Propulsive Performance Predictions for Distributed Propulsion Configurations

    Science.gov (United States)

    Borer, Nicholas K.; Derlaga, Joseph M.; Deere, Karen A.; Carter, Melissa B.; Viken, Sally A.; Patterson, Michael D.; Litherland, Brandon L.; Stoll, Alex M.

    2017-01-01

    NASA's X-57 "Maxwell" flight demonstrator incorporates distributed electric propulsion technologies in a design that will achieve a significant reduction in energy used in cruise flight. A substantial portion of these energy savings come from beneficial aerodynamic-propulsion interaction. Previous research has shown the benefits of particular instantiations of distributed propulsion, such as the use of wingtip-mounted cruise propellers and leading edge high-lift propellers. However, these benefits have not been reduced to a generalized design or analysis approach suitable for large-scale design exploration. This paper discusses the rapid, "design-order" toolchains developed to investigate the large, complex tradespace of candidate geometries for the X-57. Due to the lack of an appropriate, rigorous set of validation data, the results of these tools were compared to three different computational flow solvers for selected wing and propulsion geometries. The comparisons were conducted using a common input geometry, but otherwise different input grids and, when appropriate, different flow assumptions to bound the comparisons. The results of these studies showed that the X-57 distributed propulsion wing should be able to meet the as-designed performance in cruise flight, while also meeting or exceeding targets for high-lift generation in low-speed flight.

  6. Aero-Effected Distributed Adaptive Control of Flexible Aircraft Using Active Bleed Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed research focuses on the development of a new adaptive control methodology for active control of wing aerodynamic shape to effect distributed aerodynamic...

  7. Aerotrace. Measurement of trace species in the exhaust of aero engines

    Energy Technology Data Exchange (ETDEWEB)

    Cottington, R.V. [DRA, Farnborough (United Kingdom)

    1997-12-31

    There is growing evidence that trace species, both gaseous and particulate, play an important role in the chemistry of the atmosphere. Very little is currently known about the nature and concentration of these species emitted by aircraft engines. The purpose of AEROTRACE, therefore, is to make representative measurements of trace species emissions, such as particulates, hydrocarbon constituents and various nitrogen compounds, from engine combustors over the entire flight altitude range from ground level to cruise conditions. An overview of the programme and progress to date is presented. (author)

  8. 78 FR 49662 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Airplanes

    Science.gov (United States)

    2013-08-15

    ... INDUSTRIES S.p.A Model P-180 airplanes, all serial numbers, certificated in any category. (d) Subject Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 54; Nacelles/Pylons...

  9. Attitude Control for an Aero-Vehicle Using Vector Thrusting and Variable Speed Control Moment Gyros

    Science.gov (United States)

    Shin, Jong-Yeob; Lim, K. B.; Moerder, D. D.

    2005-01-01

    Stabilization of passively unstable thrust-levitated vehicles can require significant control inputs. Although thrust vectoring is a straightforward choice for realizing these inputs, this may lead to difficulties discussed in the paper. This paper examines supplementing thrust vectoring with Variable-Speed Control Moment Gyroscopes (VSCMGs). The paper describes how to allocate VSCMGs and the vectored thrust mechanism for attitude stabilization in frequency domain and also shows trade-off between vectored thrust and VSCMGs. Using an H2 control synthesis methodology in LMI optimization, a feedback control law is designed for a thrust-levitated research vehicle and is simulated with the full nonlinear model. It is demonstrated that VSCMGs can reduce the use of vectored thrust variation for stabilizing the hovering platform in the presence of strong wind gusts.

  10. The Hypersonic Revolution. Volume 2. From Scramjet to the National Aero-Space Plane

    Science.gov (United States)

    1995-08-01

    available to the general public, including foreign nations. This technical report has been reviewed and is approved for publica - tion. PAUL C. FEItGUSON Staff...4LU U La- 4J LUz -J z z1 MJ 0 z +11 (2) +1 t E0 CO~ * Z5e. - 0 E. co p.- CD cc4 0 L 1130 Figure 127c UjU C.’ý U U. <Ie LMU I- Z ILj C.,j 0o co I- -4

  11. Aero-Hydro-Elastic Simulation Platform for Wave Energy Systems and floating Wind Turbines

    DEFF Research Database (Denmark)

    Kallesøe, Bjarne Skovmose

    conversion platform, Poseidon, is own and operated by Floating Power Plant A/S. The platform has been operating for two test periods; one period where it was operating as a wave energy conversion platform only and one period where the three turbines was mounted and the platform operated as a combined wind...... and wave energy platform. The PSO project has equipped the platform with comprehensive measurements equipment for measuring platform motion, wave and wind conditions and turbine loads. Data from the first test period has been used for determine if the turbine could be mounted on the platform. Preliminary...... analysis of data from the second test period indicates that the platform is suitable as wind turbine foundation and that the turbines reduce the platform motion....

  12. The Process of Technology Transfer: A Case Study of the National Aero-Space Plane Program.

    Science.gov (United States)

    1995-09-01

    develop theories and provide insight into an uncharted area of study ( Bryman , 1989:174). This research design, as noted by Kervin, involves the...often characterize qualitative research ( Bryman , 1989:173,178). A final advantage of the case study method is that it is used to develop hypotheses for...November 1992). Bryman , Alan. Research Methods and Organizational Studies. Winchester MA: Unwin Hyman Inc., 1989. Chapman, Richard L. "The Federal

  13. System safety activities supporting an aero-space plane ground support technology

    Science.gov (United States)

    Mattern, Steven F.

    1992-01-01

    An overview is presented of the specific system safety activities required to support the ground support technology program associated with the design of an aerospace plane. Safe zones must be assessed to ensure that explosive safety requirements are attained to protect the vehicle, personnel, and support and operational facilities. Attention is given to the specific and unique design requirements connected with the utilization of cryogenic fuels as they apply to the design and development of an aerospace plane.

  14. Computational Aero-Acoustic Using High-order Finite-Difference Schemes

    DEFF Research Database (Denmark)

    Zhu, Wei Jun; Shen, Wen Zhong; Sørensen, Jens Nørkær

    2007-01-01

    In this paper, a high-order technique to accurately predict flow-generated noise is introduced. The technique consists of solving the viscous incompressible flow equations and inviscid acoustic equations using a incompressible/compressible splitting technique. The incompressible flow equations ar...... discretizations of the acoustic equations. The classical fourth-order Runge-Kutta time scheme is applied to the acoustic equations for time discretization....

  15. STRUCTURAL SCALE LIFE PREDICTION OF AERO STRUCTURES EXPERIENCING COMBINED EXTREME ENVIRONMENTS

    Science.gov (United States)

    2017-07-01

    superiority of tomorrow’s USAF. These platforms experience long-duration, combined and intense, thermo-mechanical-acoustic loads over significant...analysts’ past experience , a heavy reliance on testing, and limited choices to tailor material attributes. 15. SUBJECT TERMS lifing, combined environment...6 Figure 3. Correlation Between Mean Life and Deviation of Mean life with the Addition of New Metallic Systems of

  16. Bridging aero-fracture evolution with the characteristics of the acoustic emissions in a porous medium

    Directory of Open Access Journals (Sweden)

    Semih eTurkaya

    2015-09-01

    Full Text Available The characterization and understanding of rock deformation processes due to fluid flow is a challenging problem with numerous applications. The signature of this problem can be found in Earth Science and Physics, notably with applications in natural hazard understanding, mitigation or forecast (e.g. earthquakes, landslides with hydrological control, volcanic eruptions, or in industrial applications such as hydraulic-fracturing, steam-assisted gravity drainage, CO₂ sequestration operations or soil remediation. Here we investigate the link between the visual deformation and the mechanical wave signals generated due to fluid injection into porous media. In a rectangular Hele-Shaw Cell, side air injection causes burst movement and compaction of grains along with channeling (creation of high permeability channels empty of grains. During the initial compaction and emergence of the main channel, the hydraulic fracturing in the medium generates a large non-impulsive low frequency signal in the frequency range 100 Hz - 10 kHz. When the channel network is established, the relaxation of the surrounding medium causes impulsive aftershock-like events, with high frequency (above 10 kHz acoustic emissions, the rate of which follows an Omori Law. These signals and observations are comparable to seismicity induced by fluid injection. Compared to the data obtained during hydraulic fracturing operations, low frequency seismicity with evolving spectral characteristics have also been observed. An Omori-like decay of microearthquake rates is also often observed after injection shut-in, with a similar exponent p≃0.5 as observed here, where the decay rate of aftershock follows a scaling law dN/dt ∝(t-t₀-p . The physical basis for this modified Omori law is explained by pore pressure diffusion affecting the stress relaxation.

  17. Particle image velocimetry of highly luminescent, pressurized combustion flows of aero engine combustors

    OpenAIRE

    Schroll, Michael; Klinner, Joachim; Lange, Lena; Willert, Christian

    2013-01-01

    This contribution describes recent efforts leading toward the successful application of particle image velocimetry (PIV) in highly luminescent flames avoiding saturation of the second frame of commonly available double shutter PIV cameras, which is usually inevitable when using their interline-transfer CCD sensors. Information on fuel placement, reaction zone and temperature field among other quantities can be provided by frequently used spectroscopic techniques. The velocity information is o...

  18. AeroSande - ein neuer Formstoff für Geißereianwendungen

    OpenAIRE

    2003-01-01

    In the present work, organic aerogels are used as a new binding material for mould and core production in foundry application. The work is motivated by the problems occurring during the mould and core removal in aluminium casting. In contrary to steel and iron casting the low casting temperatures lead to low temperatures in the mold and core material and therefore the bonding efficiency remains on a high level. Therefore a complete core removal is only possible by an increased mechanical effo...

  19. LSST summit enclosure-facility design optimization using aero-thermal modeling

    Science.gov (United States)

    Sebag, J.; Vogiatzis, K.; Barr, J.; Neill, D.

    2012-09-01

    This paper describes Computational Fluid Dynamic (CFD) analyses combined with thermal analyses for modeling the effects of passive ventilation, enclosure-building configuration and topography on the optical performance of the Large Synoptic Survey Telescope (LSST). The primary purpose of the analyses was to evaluate the seeing contribution of the major enclosure-facility elements and to select the features to be adopted in the baseline design from among various configurations being explored by the LSST project and the contracted architectural design team. In addition, one of several simulations for different telescope orientations is presented including various wind-telescope relative azimuth angles. Using a post-processing analysis, the effects of turbulence and thermal variations within the airflow around the buildings and inside the telescope-enclosure configuration were determined, and the optical performance due to the thermal seeing along the optical path was calculated.

  20. Dual use application of killer app FHE products for Mil/Aero

    Science.gov (United States)

    Hackler, R. Douglas

    2016-05-01

    The flexible electronics industry has adopted flexible hybrid electronic (FHE) systems as a go to market strategy. High volume products are emerging for body worn bio patches, conformal structural appliques and smart labels. These products were principally developed for volume consumer and industrial market solutions but are directly applicable to advanced defense systems. This article highlights the state of the art for bio patch, conformal and smart FHE products and identifies their dual use capability for defense systems. A discussion of the manufacturing base for FHE products is presented and current experimental prototype results and performance are shared.

  1. Aero-Acoustic Optimization of the Fans and Cooling Circuit on Sncf's X 72500 Railcar

    Science.gov (United States)

    CLEON, L.-M.; WILLAIME, A.

    2000-03-01

    This paper presents the results of studies concerning the fans on SNCF's X 72500 railcar with a view to reducing the level of ambient noise. The paper first describes the operation of an axial fan and then the main sources of noise generated by this type of fan. The interactions between acoustic emissions and mass output are then described to illustrate the advantages of an acoustic and pneumatic predictive device. Finally, a new design of axial wheel on the SNCF railcar is described which has reduced the acoustic emission by 10 db whilst still improving the initial ventilation performance.

  2. Analyses of the mechanisms of amplitude modulation of aero-acoustic wind turbine sound

    DEFF Research Database (Denmark)

    Fischer, Andreas; Aagaard Madsen, Helge; Kragh, Knud Abildgaard

    2014-01-01

    This paper explores the source mechanism which cause amplitude modulation of the emitted sound of a wind turbine at large distances from the turbine, named as other amplitude modulation. Measurements of the fluctuating surface pressure on a 2.3MW wind turbine showed a considerable variation over...... a blade revolution in the presence of angle of attack variations. If the blade undergoes transient stall, the variation of the surface pressure spectrum was enhanced and shifted to frequencies below 200Hz. The surface pressure spectra could be directly related to the emitted far eld sound. These ndings...

  3. Scalable, Lightweight, Low-Cost Aero/Electrodynamic Drag Deorbit Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will develop the "Terminator Tape Deorbit Module", a lightweight, low-cost, scalable de-orbit module that will utilize both aerodynamic drag...

  4. Delineation of a shallow subsurface aquiclude relief with aero electromagnetic data

    Science.gov (United States)

    Römer, A.; Winkler, E.; Bieber, G.; Motschka, K.; Reitner, H.

    2009-04-01

    Within a governmental groundwater remediation project in Austria, a new (overworked) characterization of a large catchment area (600 km2) with aeroelectromagnetics (AEM) was carried out. This catchment area is a large and important zone of subsurface water resources for currently and future municipal and rural water supply. Conflicts in future land use between e.g. agricultura, excavigation of mass materials, city and regional planning, ect. are preassigned and have impacts concerning the quality and quantity of available groundwater. The geology of the investigation area is a typical post-glacial region, characterized by aggradational deposition areas. The thickness of the wide-spread terrace gravels ranges from 10m to 40m, being the preferred ground water aquifer. The subsurface of the investigation area is built up by a Neogen basement, the so called Molasse and is acting as an aquiclude relative to the overlying quaternary sediments. Aeroelectromagnetic data from a former aerogeophysical survey were reinterpreted with a new processing and interpretation approach for the determination of this geological 3 layer case. This aeroelectromagnetic inversion integrates results from borehole data, ground geoelectric surveys and from geological mapping as a priori input information. The inversion result for a measured AEM data value is determined by a combination of geostatistically weighted additional information and likelihood weighted theoretical models. The primary aim of the study was the delineation of the aquiclude relief. The ground water circulation within the different terrace gravels is substantially affected by this Neogen relief. Depressions and prequaternary (tertiary) riverbeds within the Molasse often show other trends of water flow than the surficial, recent vales. The knowledge of the hydrogeological framework is essential for identification and definition of water protection and catchment areas as a decision base for national land use regulations. The result is a topographic model of the aquiclude with a depth resolution of ±5m.

  5. Auto-measuring system of aero-camera lens focus using linear CCD

    Science.gov (United States)

    Zhang, Yu-ye; Zhao, Yu-liang; Wang, Shu-juan

    2014-09-01

    The automatic and accurate focal length measurement of aviation camera lens is of great significance and practical value. The traditional measurement method depends on the human eye to read the scribed line on the focal plane of parallel light pipe by means of reading microscope. The method is of low efficiency and the measuring results are influenced by artificial factors easily. Our method used linear array solid-state image sensor instead of reading microscope to transfer the imaging size of specific object to be electrical signal pulse width, and used computer to measure the focal length automatically. In the process of measurement, the lens to be tested placed in front of the object lens of parallel light tube. A couple of scribed line on the surface of the parallel light pipe's focal plane were imaging on the focal plane of the lens to be tested. Placed the linear CCD drive circuit on the image plane, the linear CCD can convert the light intensity distribution of one dimension signal into time series of electrical signals. After converting, a path of electrical signals is directly brought to the video monitor by image acquisition card for optical path adjustment and focusing. The other path of electrical signals is processed to obtain the pulse width corresponding to the scribed line by electrical circuit. The computer processed the pulse width and output focal length measurement result. Practical measurement results showed that the relative error was about 0.10%, which was in good agreement with the theory.

  6. Planform, aero-structural, and flight control optimization for tailless morphing aircraft

    Science.gov (United States)

    Molinari, Giulio; Arrieta, Andres F.; Ermanni, Paolo

    2015-04-01

    Tailless airplanes with swept wings rely on variations of the spanwise lift distribution to provide controllability in roll, pitch and yaw. Conventionally, this is achieved utilizing multiple control surfaces, such as elevons, on the wing trailing edge. As every flight condition requires different control moments (e.g. to provide pitching moment equilibrium), these surfaces are practically permanently displaced. Due to their nature, causing discontinuities, corners and gaps, they bear aerodynamic penalties, mostly in terms of shape drag. Shape adaptation, by means of chordwise morphing, has the potential of varying the lift of a wing section by deforming its profile in a way that minimizes the resulting drag. Furthermore, as the shape can be varied differently along the wingspan, the lift distribution can be tailored to each specific flight condition. For this reason, tailless aircraft appear as a prime choice to apply morphing techniques, as the attainable benefits are potentially significant. In this work, we present a methodology to determine the optimal planform, profile shape, and morphing structure for a tailless aircraft. The employed morphing concept is based on a distributed compliance structure, actuated by Macro Fiber Composite (MFC) piezoelectric elements. The multidisciplinary optimization is performed considering the static and dynamic aeroelastic behavior of the resulting structure. The goal is the maximization of the aerodynamic efficiency while guaranteeing the controllability of the plane, by means of morphing, in a set of flight conditions.

  7. Research on Aero-Thermodynamic Distortion Induced Structural Dynamic Response of Multistage Compressor Blading

    Science.gov (United States)

    1992-03-01

    compresor operating point. Also, the reduced steady surface pressure distributions and steady lift for thesolidity has much higher pressure differences and...including stall flutter and dynamic stall , Received May 9. 198 revision received Oct. 10. 1988. Copyright also have been addressed. Thus, oscillating...function, with the last ’ 2Yashima. S., and Tanaka. H.. "Torsional Flutter in Stalled stage stator vane row replaced with isolated instrumented Cascade

  8. Foundational Aero Research for Development of Efficient Power Turbines With 50% Variable-speed Capability

    Science.gov (United States)

    2011-02-01

    profile (+ shock) loss coefficients as a function of incidence for L1M blading22 at Recx,2 = 620k and 62k and Mr,2 = 0.72: (a) loss bucket ; and (b...in, leading to chord Reynolds numbers associated with transitional suction -sides (Haselbach et al., 2002, and Praisner et al., 2007). 3.1.5 Design...selected strongly affected the location of transition on the suction side. The C-grids used were generated using the Grids About Airfoils Using

  9. 2009 Aero-Metric Inc. Topographic LiDAR: Yukon Flats, Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This delivery contains point cloud data in LAS 1.2 format, classified in the following manner. Class 1: Unclassified and Class 2: Ground. Overlap points have been...

  10. 2009 Aero-Metric Inc. Topographic LiDAR: North Slope Coastal Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This delivery contains point cloud data in LAS 1.2 format, with Absolute GPS Timestamps. No classification has been completed on these data. The nominal point...

  11. Individual hollow and mesoporous aero-graphitic microtube based devices for gas sensing applications

    Science.gov (United States)

    Lupan, Oleg; Postica, Vasile; Marx, Janik; Mecklenburg, Matthias; Mishra, Yogendra K.; Schulte, Karl; Fiedler, Bodo; Adelung, Rainer

    2017-06-01

    In this work, individual hollow and mesoporous graphitic microtubes were integrated into electronic devices using a FIB/SEM system and were investigated as gas and vapor sensors by applying different bias voltages (in the range of 10 mV-1 V). By increasing the bias voltage, a slight current enhancement is observed, which is mainly attributed to the self-heating effect. A different behavior of ammonia NH3 vapor sensing by increasing the applied bias voltage for hollow and mesoporous microtubes with diameters down to 300 nm is reported. In the case of the hollow microtube, an increase in the response was observed, while a reverse effect has been noticed for the mesoporous microtube. It might be explained on the basis of the higher specific surface area (SSA) of the mesoporous microtube compared to the hollow one. Thus, at room temperature when the surface chemical reaction rate (k) prevails on the gas diffusion rate (DK) the structures with a larger SSA possess a higher response. By increasing the bias voltage, i.e., the overall temperature of the structure, DK becomes a limiting step in the gas response. Therefore, at higher bias voltages the larger pores will facilitate an enhanced gas diffusion, i.e., a higher gas response. The present study demonstrates the importance of the material porosity towards gas sensing applications.

  12. Failure Prediction in Fiber Metal Laminates for Next Generation Aero Materials

    Science.gov (United States)

    Jeevan Rao, H.; Janaki Ramulu, Perumalla; Vishnu Vardhan, M.; Chandramouli, CH

    2016-09-01

    In aerospace industry, there is huge demand for low density and low cost materials with better mechanical properties. In this view, there are many researchers developed new materials interms of composites. Similar manner, the present paper also aimed to produce a new approach for cost effective materials of 3D weaved glass fiber metal laminates (FML) with different compositions using a numerical study. A method for the simulation of progressive delamination based on de-cohesion elements has been presented. De-cohesion elements are placed between layers of solid elements that open and shear in response to the loading situation. The onset of damage and the growth of delamination are simulated without previous knowledge about the location, the size, or the direction of propagation of the de-laminations. A softening law for mixed-mode delamination that can be applied to any interaction criterion is also proposed. The constitutive equation proposed uses a single variable, the maximum relative displacement, to track the damage at the interface under general loading conditions. The material properties required to define the element constitutive equation are the inter-laminar fracture toughness's, the penalty stiffness, and the strengths.

  13. Nonlinear AeroServoElastic Reduced Order Model for Active Structural Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the proposed effort is to develop and demonstrate rigorous model order reduction (MOR) technologies to automatically generate fully coupled,...

  14. Shock Response and Dynamic Failure of Spatially Tailored Aero-Thermal Structures

    Science.gov (United States)

    2012-09-15

    and Nanolayered Titanium Aluminum Carbide (a MAX phase material) under varying rates of loading and at different temperatures. The Johnson - Cook ...Development of Johnson - Cook constitutive model for Hastelloy X at different temperatures and strain rates.  Analytical development of steady...which it showed a peak at 900°C before beginning to decrease again as the temperature was further increased. The Johnson - Cook model was used to predict

  15. 77 FR 30371 - Airworthiness Directives; International Aero Engines AG Turbofan Engines

    Science.gov (United States)

    2012-05-23

    ... Jersey Avenue SE., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Carlos Fernandes, Aerospace... ceramic liner for staining or axial cracking, or, that we specify accept/reject criteria for staining and cracking of the ceramic liner. They also requested that we delay blending limit measurements of the...

  16. Mobile System for Precise Aero Delivery with Global Reach Network Capability

    Science.gov (United States)

    2009-08-30

    autonomous powered paraglider (LEAPP) developed under contract with DARPA (Fig.9b). a) b) Fig. 9. Onyx ML with mock sensor payload release...canister (a) and powered paraglider LEAPP (b). Compared to the Snowflake ADS / Arcturus UAS this system has: - Moth mode control for a parafoil

  17. Aerosols at the Poles: An AeroCom Phase II Multi-Model Evaluation

    Science.gov (United States)

    Sand, M.; Samset, B. H.

    2016-12-01

    Atmospheric aerosols from anthropogenic and natural sources reach the Polar Regions through long-range transport. By scattering and absorbing solar radiation, aerosols perturb the energy balance in the region and may have played a significant role in recent Arctic warming. Aerosols in Polar regions are however, poorly constrained in present day global climate models. Here we compare aerosol burdens from simulations with 16 global aerosol models from the Aerocom phase II model inter-comparison project with available observations at both Poles. We show that the annual mean multi-model median Aerosol Optical Depth (AOD) is not a bad representation of the measured AOD in Arctic, even though the model spread is large. The models tend to underestimate the spring maximum and overestimate the summer/autumn minimum. We also document the geographical distribution and seasonal cycle of aerosol burdens and shortwave anthropogenic direct radiative forcing (DRF) of the total aerosol and the individual aerosol species; black carbon (BC), sulfate, and primary organic aerosols from fossil/bio fuel and biomass burning, dust and sea-salt. A subset of models has also reported nitrate and secondary organic aerosols. The models produce an annual mean median AOD 0.07 in the Arctic and 0.01 the Antarctic. The Arctic modeled annual mean DRF is slightly negative -0.12 Wm-2, dominated by a positive black carbon DRF during spring and a negative sulfate DRF during summer. We perform sensitivity experiments with one of the Aerocom models (GISS modelE) to investigate how regional emissions of BC and sulfate and the lifetime of BC influence the Arctic and Antarctic aerosol burdens.

  18. Application of Weakest Link Probabilistic Framework for Fatigue Notch Factor to Aero Engine Materials

    Science.gov (United States)

    2014-08-25

    where m  is the density of mobile dislocation, b is the burgers vector and v  is the average velocity of the burgers vector. Using Equations...complicated interaction of dislocations created by cross slip which result in an increased dislocation density and restricts the motion of mobile ...137, pp. 173-210 , 2006. [150] McGinty R D , "Multiscale representation of polycrystaline inelasticity PhD Thesis," Georgia Institute of Technolgy , Atlanta USA , 2001.

  19. Aero Propulsion and Power Directorate The McCook Field Years (1917-1927)

    Science.gov (United States)

    1995-02-01

    and $3 million producing the Hispano- Suiza engine, and achieved only limited production. Similar results were experienced producing the Le Rhone, the...foreign types, mostly Hispano- Suiza and Le Rhones.79 The weight of the Liberty 12-cylinder varied depending on accessories and equipment. The basic engine...of Mercedes, Rolls-Royce, and Lorraine-Dietrich camshaft based on Mercedes, Hispano- Suiza , Rolls-Royce, Renault, Fiat, and Hall-Scott 45-degree angle

  20. A Post-Processing System for Physics Based Derived Rotorcraft Computational Aero-Acoustics Simulations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Light, the makers of the FIELDVIEW CFD post-processing software, in response to NASA SBIR Phase 1 solicitation, proposes an effort that addresses A2.10...

  1. A Post-Processing System for Physics Based Derived Rotorcraft Computational Aero-Acoustics Simulations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Light, the makers of the FIELDVIEW CFD post-processing software, in response to NASA SBIR Phase 2 solicitation, proposes an effort that addresses A2.10...

  2. AAtS over AeroMACS Technology Trials on the Airport Surface

    Science.gov (United States)

    Apaza, Rafael; Abraham, Biruk; Maeda, Toshihide

    2016-01-01

    Air-Ground component of SWIM; Enables enhanced two-way information exchanges between flight operators, aircrew, and ATSP (TFM); Used in all flight domains including pre-departure and post-arrival; Aircrew active in CDM; For strategic planning, advisory information; Not for command control (data voice) Wireless communications system for airport surface; Family member of Mobile WiMAX: (IEEE802.16e), Band 5091-5150 MHz, Bandwidth 5 MHz - TDDOFDMA - Adaptive Modulation and Coding - Quality of Service (QoS)

  3. Unsteady Aero Computation of a 1 1/2 Stage Large Scale Rotating Turbine

    Science.gov (United States)

    To, Wai-Ming

    2012-01-01

    This report is the documentation of the work performed for the Subsonic Rotary Wing Project under the NASA s Fundamental Aeronautics Program. It was funded through Task Number NNC10E420T under GESS-2 Contract NNC06BA07B in the period of 10/1/2010 to 8/31/2011. The objective of the task is to provide support for the development of variable speed power turbine technology through application of computational fluid dynamics analyses. This includes work elements in mesh generation, multistage URANS simulations, and post-processing of the simulation results for comparison with the experimental data. The unsteady CFD calculations were performed with the TURBO code running in multistage single passage (phase lag) mode. Meshes for the blade rows were generated with the NASA developed TCGRID code. The CFD performance is assessed and improvements are recommended for future research in this area. For that, the United Technologies Research Center's 1 1/2 stage Large Scale Rotating Turbine was selected to be the candidate engine configuration for this computational effort because of the completeness and availability of the data.

  4. 2009 Aero-Metric Inc. Topographic LiDAR: Yukon Flats, Alaska

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This delivery contains point cloud data in LAS 1.2 format, classified in the following manner. Class 1: Unclassified and Class 2: Ground. Overlap points have been...

  5. Experience with Aero- and Fluid-Dynamic Testing for Engineering and CFD Validation

    Science.gov (United States)

    Ross, James C.

    2016-01-01

    Ever since computations have been used to simulate aerodynamics the need to ensure that the computations adequately represent real life has followed. Many experiments have been performed specifically for validation and as computational methods have improved, so have the validation experiments. Validation is also a moving target because computational methods improve requiring validation for the new aspect of flow physics that the computations aim to capture. Concurrently, new measurement techniques are being developed that can help capture more detailed flow features pressure sensitive paint (PSP) and particle image velocimetry (PIV) come to mind. This paper will present various wind-tunnel tests the author has been involved with and how they were used for validation of various kinds of CFD. A particular focus is the application of advanced measurement techniques to flow fields (and geometries) that had proven to be difficult to predict computationally. Many of these difficult flow problems arose from engineering and development problems that needed to be solved for a particular vehicle or research program. In some cases the experiments required to solve the engineering problems were refined to provide valuable CFD validation data in addition to the primary engineering data. All of these experiments have provided physical insight and validation data for a wide range of aerodynamic and acoustic phenomena for vehicles ranging from tractor-trailers to crewed spacecraft.

  6. Clinical significance identification in the of aero-allergen western Cape

    African Journals Online (AJOL)

    1991-01-19

    Jan 19, 1991 ... A 7-day Burkard spore trap mounted at a height of 3 m from the ground at the Red ... forearm at 2 cm intervals. The skin was pricked ..... human immunogenic response - enhanced IgE-mediated reactivity to common inhaled ...

  7. Opto-mechanical design of optical window for aero-optics effect simulation instruments

    Science.gov (United States)

    Wang, Guo-ming; Dong, Dengfeng; Zhou, Weihu; Ming, Xing; Zhang, Yan

    2016-10-01

    A complete theory is established for opto-mechanical systems design of the window in this paper, which can make the design more rigorous .There are three steps about the design. First, the universal model of aerodynamic environment is established based on the theory of Computational Fluid Dynamics, and the pneumatic pressure distribution and temperature data of optical window surface is obtained when aircraft flies in 5-30km altitude, 0.5-3Ma speed and 0-30°angle of attack. The temperature and pressure distribution values for the maximum constraint is selected as the initial value of external conditions on the optical window surface. Then, the optical window and mechanical structure are designed, which is also divided into two parts: First, mechanical structure which meet requirements of the security and tightness is designed. Finally, rigorous analysis and evaluation are given about the structure of optics and mechanics we have designed. There are two parts to be analyzed. First, the Fluid-Solid-Heat Coupled Model is given based on finite element analysis. And the deformation of the glass and structure can be obtained by the model, which can assess the feasibility of the designed optical windows and ancillary structure; Second, the new optical surface is fitted by Zernike polynomials according to the deformation of the surface of the optical window, which can evaluate imaging quality impact of spectral camera by the deformation of window.

  8. Trajectories to the outer planets using aero-gravity assist flybys of Venus and Mars

    Science.gov (United States)

    Bender, David F.

    1992-01-01

    The trajectory concept used here is to flyby Venus and then Mars with moderately high speeds expecting to use both gravity and aeroassisted (wave rider) turns in the atmospheres of the planets in order to form fast trajectories to the planets beyond Jupiter. The first part of the paper contains a description of the development of earth-Venus-Mars trajectories yielding the required speeds at Mars in the interval 2001 to 2015. The second part consists in identifying cases in which Mars is at the proper longitude for each target and obtaining trajectories. Trajectories to Saturn, Uranus, Neptune, and Pluto have been found.

  9. Aero-Mechanical Design Methodology for Subsonic Civil Transport High-Lift Systems

    Science.gov (United States)

    vanDam, C. P.; Shaw, S. G.; VanderKam, J. C.; Brodeur, R. R.; Rudolph, P. K. C.; Kinney, D.

    2000-01-01

    In today's highly competitive and economically driven commercial aviation market, the trend is to make aircraft systems simpler and to shorten their design cycle which reduces recurring, non-recurring and operating costs. One such system is the high-lift system. A methodology has been developed which merges aerodynamic data with kinematic analysis of the trailing-edge flap mechanism with minimum mechanism definition required. This methodology provides quick and accurate aerodynamic performance prediction for a given flap deployment mechanism early on in the high-lift system preliminary design stage. Sample analysis results for four different deployment mechanisms are presented as well as descriptions of the aerodynamic and mechanism data required for evaluation. Extensions to interactive design capabilities are also discussed.

  10. Processing of Advanced Ceramics Which Have Potential for Use in Gas Turbine Aero Engines

    Science.gov (United States)

    1989-02-01

    des agents de densification, bien que cela ait pu avoir des effets n.fastes z,-r lcz propridtes du mat~riau A hautes temp6ratures. Finalement, on...6 sous iridc sans agent de densificatioi., puibse etre une methode attrayante de fabrication de mathriaux composites A base de c~ramiques, et d’autre

  11. Design, techno-economic and environmental risk assessment of aero-derivative industrial gas turbine

    OpenAIRE

    Abaad, Abdelmanam Abaad Abdelsalam

    2012-01-01

    Increased availability of natural gas has boosted research and development efforts to further increase gas turbine performance. Performance has been increased remarkably and unit cost reduced due to achievements gained in improving thermodynamic cycles and cooling technologies. However, increased complexity in power industry regulations and fluctuations in fuel price have indicated that all the aforementioned improvements in gas turbine performance could not cope with the in...

  12. The Aero-Resonator Power Plant of the V-1 Flying Bomb

    Science.gov (United States)

    1948-06-30

    shows the design proposal of Lorin, which was described in 1908. This scheme depended on Otto - engine construction, the exhaust gases passing through...of the Otto engine or explosion turbine as shown in Figures 1 and 2. Their technical pedigree lies much closer to that of acoustic machines, which...valve using parts from an Otto engine . The machine was used to give a comparison of flap endurances under various loads

  13. Active Flutter Suppression Using Cooperative, High Frequency, Dynamic-Resonant Aero-Effectors

    Science.gov (United States)

    2006-12-13

    no person shall be subject to any penalty for failing to comply with a collection of infornation if it does not display a currently valid OMO ...initially are of the same dimension as the fence. Subsequent tracking of these structures indicate that they diminish in strength and are differentially...characterized by a vortex strength , K. Additionally, the advection velocity ratio (for a vortex in an inviscid fluid adjacent to a boundary) is proportional

  14. Bridging aero-fracture evolution with the characteristics of the acoustic emissions in a porous medium

    Science.gov (United States)

    Turkaya, Semih; Toussaint, Renaud; Eriksen, Fredrik; Zecevic, Megan; Daniel, Guillaume; Flekkøy, Eirik; Måløy, Knut Jørgen

    2015-09-01

    The characterization and understanding of rock deformation processes due to fluid flow is a challenging problem with numerous applications. The signature of this problem can be found in Earth Science and Physics, notably with applications in natural hazard understanding, mitigation or forecast (e.g. earthquakes, landslides with hydrological control, volcanic eruptions), or in industrial applications such as hydraulic-fracturing, steam-assisted gravity drainage, CO sequestration operations or soil remediation. Here we investigate the link between the visual deformation and the mechanical wave signals generated due to fluid injection into porous media. In a rectangular Hele-Shaw Cell, side air injection causes burst movement and compaction of grains along with channeling (creation of high permeability channels empty of grains). During the initial compaction and emergence of the main channel, the hydraulic fracturing in the medium generates a large non-impulsive low frequency signal in the frequency range 100 Hz - 10 kHz. When the channel network is established, the relaxation of the surrounding medium causes impulsive aftershock-like events, with high frequency (above 10 kHz) acoustic emissions, the rate of which follows an Omori Law. These signals and observations are comparable to seismicity induced by fluid injection. Compared to the data obtained during hydraulic fracturing operations, low frequency seismicity with evolving spectral characteristics have also been observed. An Omori-like decay of microearthquake rates is also often observed after injection shut-in, with a similar exponent p≃0.5 as observed here, where the decay rate of aftershock follows a scaling law dN/dt ∝(t-t₀ )-p . The physical basis for this modified Omori law is explained by pore pressure diffusion affecting the stress relaxation.

  15. Collaborative Software Development in Support of Fast Adaptive AeroSpace Tools (FAAST)

    Science.gov (United States)

    Kleb, William L.; Nielsen, Eric J.; Gnoffo, Peter A.; Park, Michael A.; Wood, William A.

    2003-01-01

    A collaborative software development approach is described. The software product is an adaptation of proven computational capabilities combined with new capabilities to form the Agency's next generation aerothermodynamic and aerodynamic analysis and design tools. To efficiently produce a cohesive, robust, and extensible software suite, the approach uses agile software development techniques; specifically, project retrospectives, the Scrum status meeting format, and a subset of Extreme Programming's coding practices are employed. Examples are provided which demonstrate the substantial benefits derived from employing these practices. Also included is a discussion of issues encountered when porting legacy Fortran 77 code to Fortran 95 and a Fortran 95 coding standard.

  16. Presentations from the Aeroelastic Workshop – latest results from AeroOpt

    DEFF Research Database (Denmark)

    Hansen, Morten Hartvig

    This report contains the slides of the presentations at the Aeroelastic Workshop held at Risø-DTU for the wind energy industry in Denmark on January 27, 2011. The scientific part of the agenda at this workshop was • Anisotropic beam element in HAWC2 for modelling of composite lay-ups (Taeseong Kim...... (Robert Mikkelsen) • Potential of fatigue and extreme load reductions on swept blades using HAWC2 (David Verelst) • Aeroelastic modal analysis of backward swept blades using HAWCStab2 (Morten H. Hansen) • Aeroelastic rotor design minimizing the loads (Christian Bak) • A small study of flat back airfoils...

  17. Ultra-High Temperature Metallic Seal/Energizer Development for Aero Propulsion and Gas Turbine Applications

    Science.gov (United States)

    Cornett, Ken; Newman, Jesse; Datta, Amit

    2009-01-01

    The industry is requiring seals to operate at higher and higher temperatures. Traditional static seal designs and materials experience stress relaxation, losing their ability to maintain contact with moving flanges. Ultra High Temperature seal development program is a multiphase program with incremental increases in seal operating temperatures.

  18. Integrated Aero-Servo-Thermo-Propulso-Elasticity (ASTPE) for Hypersonic Scramjet Vehicle Design/Analysis

    Science.gov (United States)

    2009-12-04

    reaction mechanism used in this study is a subset of the full reaction mechanism from Kundu et. al [2.10]. The reaction mechanism consists of 17...of ASPE would be otherwise far too complex as a system to handle. To do so, however, requires in depth physical understanding of the mechanism and...geometric design variables, as shown in Figure 2.2. The computational fluid dynamics validation cases shown in Figure 2.3 show the power of the

  19. Design and Aero-elastic Simulation of a 5MW Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Vita, Luca; Schmidt Paulsen, Uwe; Aagaard Madsen, Helge;

    2013-01-01

    technology, which can be improved in the future with new dedicated technological solutions. The rotor uses curved blades, which are designed in order to minimize the gravitational loads and to be produced by the pultrusion process. The floating platform is a slender cylindrical structure rotating along......-DTU. The numerical simulations take into account the fully coupled aerodynamic and hydrodynamic loads on the structure, due to wind, waves and currents. The turbine is tested in operative conditions, at different sea states, selected according to the international offshore standards. The research is part...

  20. Evaluation of Aero Commander sidewall vibration and interior acoustic data: Static operations

    Science.gov (United States)

    Piersol, A. G.; Wilby, E. G.; Wilby, J. F.

    1980-01-01

    Results for the vibration measured at five locations on the fuselage structure during static operations are presented. The analysis was concerned with the magnitude of the vibration and the relative phase between different locations, the frequency response (inertance) functions between the exterior pressure field and the vibration, and the coherent output power functions at interior microphone locations based on sidewall vibration. Fuselage skin panels near the plane of rotation of the propeller accept propeller noise excitation more efficiently than they do exhaust noise.

  1. LES/RANS Modeling of Aero-Optical Effects in a Supersonic Cavity Flow

    Science.gov (United States)

    2016-06-13

    disturbances create eddy shocklets that propagate into the free-stream and create additional optical path disturbances. 15. SUBJECT TERMS 16. SECURITY ...Proceedings of the third AFOSR International Conference on DNS /LES, 2000 [19] Sirovich, L. “Turbulence and the dynamics of coherent structures.” I—III

  2. Intercomparison and Evaluation of Global Aerosol Microphysical Properties among AeroCom Models of a Range of Complexity

    Energy Technology Data Exchange (ETDEWEB)

    Mann, G. W.; Carslaw, K. S.; Reddington, C. L.; Pringle, K. J.; Schulz, M.; Asmi, A.; Spracklen, D. V.; Ridley, D. A.; Woodhouse, M. T.; Lee, L. A.; Zhang, Kai; Ghan, Steven J.; Easter, Richard C.; Liu, Xiaohong; Stier, P.; Lee, Y. H.; Adams, P. J.; Tost, H.; Lelieveld, J.; Bauer, S.; Tsigaridis, Kostas; van Noije, T.; Strunk, A.; Vignati, E.; Bellouin, N.; Dalvi, M.; Johnson, C. E.; Bergman, T.; Kokkola, H.; Von Salzen, Knut; Yu, Fangqun; Luo, Gan; Petzold, A.; Heintzenberg, J.; Clarke, A. D.; Ogren, J. A.; Gras, J.; Baltensperger, Urs; Kaminski, U.; Jennings, S. G.; O' Dowd, C. D.; Harrison, R. M.; Beddows, D. C.; Kulmala, M.; Viisanen, Y.; Ulevicius, V.; Mihalopoulos, Nikos; Zdimal, V.; Fiebig, M.; Hansson, H. C.; Swietlicki, E.; Henzing, J. S.

    2014-05-13

    Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical properties and cloud condensation nuclei (CCN) concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study examines the global variation in particle size distribution simulated by twelve global aerosol microphysics models to quantify model diversity and to identify any common biases against observations. Evaluation against size distribution measurements from a new European network of aerosol supersites shows that the mean model agrees quite well with the observations at many sites on the annual mean, but there are some seasonal biases common to many sites. In particular, at many of these European sites, the accumulation mode number concentration is biased low during winter and Aitken mode concentrations tend to be overestimated in winter and underestimated in summer. At high northern latitudes, the models strongly underpredict Aitken and accumulation particle concentrations compared to the measurements, consistent with previous studies that have highlighted the poor performance of global aerosol models in the Arctic. In the marine boundary layer, the models capture the observed meridional variation in the size distribution, which is dominated by the Aitken mode at high latitudes, with an increasing concentration of accumulation particles with decreasing latitude. Considering vertical profiles, the models reproduce the observed peak in total particle concentrations in the upper troposphere due to new particle formation, although modelled peak concentrations tend to be biased high over Europe. Overall, the results suggest that most global aerosol microphysics models simulate the global variation of the particle size distribution with a good degree of skill, but some models are in poor agreement with the observations. Further work is required to better constrain size-resolved primary and secondary particle number sources, and an improved understanding of nucleation and growth (e.g. the role of nitrate and secondary organics) will improve the fidelity of simulated particle size distributions.

  3. Optimization of Simplex Atomizer Inlet Port Configuration through Computational Fluid Dynamics and Experimental Study for Aero-Gas Turbine Applications

    Science.gov (United States)

    Marudhappan, Raja; Chandrasekhar, Udayagiri; Hemachandra Reddy, Koni

    2016-06-01

    The design of plain orifice simplex atomizer for use in the annular combustion system of 1100 kW turbo shaft engine is optimized. The discrete flow field of jet fuel inside the swirl chamber of the atomizer and up to 1.0 mm downstream of the atomizer exit are simulated using commercial Computational Fluid Dynamics (CFD) software. The Euler-Euler multiphase model is used to solve two sets of momentum equations for liquid and gaseous phases and the volume fraction of each phase is tracked throughout the computational domain. The atomizer design is optimized after performing several 2D axis symmetric analyses with swirl and the optimized inlet port design parameters are used for 3D simulation. The Volume Of Fluid (VOF) multiphase model is used in the simulation. The orifice exit diameter is 0.6 mm. The atomizer is fabricated with the optimized geometric parameters. The performance of the atomizer is tested in the laboratory. The experimental observations are compared with the results obtained from 2D and 3D CFD simulations. The simulated velocity components, pressure field, streamlines and air core dynamics along the atomizer axis are compared to previous research works and found satisfactory. The work has led to a novel approach in the design of pressure swirl atomizer.

  4. An Investigation into the Comparative Costs of Additive Manufacture vs. Machine from Solid for Aero Engine Parts

    Science.gov (United States)

    2006-05-01

    Shape Processing (Rentabilite de fabrication par un traitement de finition immediate), The original document contains color images. 14. ABSTRACT 15...removal of surface finish effects and to allow for slight thermal distortion effects on cooling. 1.2.2 Additive Manufacturing Process The method of...its forming temperature. A machining allowance is also provided to allow surface effects such as skin stresses and oxidation caused by the forging

  5. A Program of Research and Education to Advance the Design, Synthesis, and Optimization of Aero-Space System Concepts

    Science.gov (United States)

    Sandusky, Robert

    2002-01-01

    Since its inception in December 1999, the program has provided support for a total of 11 Graduate Research Scholar Assistants, of these, 6 have completed their MS degree program. The program has generated 3 MS theses and a total of 4 publications/presentations.

  6. The influence of fully nonlinear wave forces on aero-hydro-elastic calculations of monopile wind turbines

    DEFF Research Database (Denmark)

    Schløer, Signe; Bredmose, Henrik; Bingham, Harry B.

    2016-01-01

    and nonlinear irregular wave realizations are calculated using the fully nonlinear potential flow wave model OceanWave3D [1]. The linear and nonlinear wave realizations are compared using both a static analysis on a fixed monopile and dynamic calculations with the aeroelastic code Flex5 [2]. The conclusion from...... this analysis is that linear wave theory is generally sufficient for estimating the fatigue loading, but wave nonlinearity is important in determining the ultimate design loads.......The response of an offshore wind turbine tower and its monopile foundation has been investigated when exposed to linear and fully nonlinear irregular waves on four different water depths. The investigation focuses on the consequences of including full nonlinearity in the wave kinematics. The linear...

  7. Aero radiometric measurements in the framework of the ARM06 experiment; Aeroradiometrische Messungen im Rahmen der Uebung ARM06

    Energy Technology Data Exchange (ETDEWEB)

    Bucher, B.; Butterweck, G.; Rybach, L.; Schwarz, G

    2007-02-15

    The measurement flights of the exercise ARM06 were performed between 19th and 22nd of June 2006 under the direction of Y. Loertscher of the National Emergency Operations Centre (NAZ) and coordination by the Expert Group for Aeroradiometrics (FAR). According to the alternating schedule of the annual ARM exercises, the environs of the nuclear power plants Beznau (KKB) and Leibstadt (KKL), of the Paul Scherrer Institut (PSI) research facility and of the Intermediate Storage Facility for Nuclear Waste (ZWILAG) were inspected. The measurements showed similar results to those obtained in former years. Additionally, a neutron detector provided by the Kompetenzzentrum ABC Spiez was employed during these flights. With this detector, the neutron radiation of the proton accelerator of PSI was detected, whereas the nuclear power plants and ZWILAG showed no increase of neutron count rate. The measurements above cities were continued with the cities of Neuchatel and La Chaux-de-Fonds. Western Switzerland was largely spared from Chernobyl fallout, a fact which was reflected in the results of the airborne gamma spectroscopic (ARM) measurements. Training of the measuring teams was intensified with two dedicated training flights in the vicinity of Unteriberg (SZ) and Rothenthurm (SZ). A training search for radioactive sources was performed together with the local emergency response forces in the vicinity of Le Cerneux-Pequinot (NE). The calibration of the ARM equipment was checked with in-situ gamma spectroscopic and ambient dose equivalent rate measurements performed near Biaufond (NE, JU) by teams from Spiez Laboratory, Institut Universitaire de Radiophysique Appliquee (IRA), Sektion Ueberwachung der Radioaktivitaet (SueR) of the Federal Office of Public Health (FOPH) and the Swiss Federal Nuclear Safety Inspectorate (HSK) . The railway line between Berne and Zurich was inspected with airborne gamma spectroscopy due to a request from the Swiss National Railways (SBB). (author)

  8. Yip - Development and Application of a High-Speed Three-Dimensional Density Measurement Technique for Aero-Optic Applications

    Science.gov (United States)

    2011-03-25

    Fuel Distributions in an HCCI Engine ." (Proceedings of the Combustion Institute) 29, pp. 679-685 (2002). Ponder, Z.B., Rennie, R.M., Abado, S., and...Aerospace Engineering 211 Davis Hall Auburn University, AL 36849-5338 (334) 844-6827 thurow@auburn.edu http://www.eng.auburn.edu/users/thurobs/ 1...performed. (Nygren, et al. 2002) successfully performed 3-D acetone LIF (acetone mixed with ethanol) to study fuel location and concentration in an HCCI

  9. 75 FR 5695 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-02-04

    ... have the same cracks. Although calculations confirm the low stress level in that area, a reinforcement... inspection and a reinforcement--by installation of doublers--of the ``0'' pressure bulkhead. This AD also... economic impact, positive or negative, on a substantial number of small entities under the criteria of...

  10. Solid Oxide Fuel Cell/Turbine Hybrid Power System for Advanced Aero-propulsion and Power Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Solid oxide fuel cell (SOFC)/ gas turbine hybrid power systems (HPSs) have been recognized by federal agencies and other entities as having the potential to operate...

  11. Clinical Study of Aero-otitis Media%航空性中耳炎的临床探讨

    Institute of Scientific and Technical Information of China (English)

    郭庭梅

    2015-01-01

    Objective To study the clinical symptoms analysis of aviation otitis media.Methods Between January 2010 and January 2015 in our hospital 12 crew and passengers 8 diagnostic data were retrospectively analyzed, through to summarize the clinical data and the knowledge of aviation otitis media of the pathogenic factors and clinical symptoms.Results 20 cases, 2 cases diagnosed by aviation sex otitis media caused by eustachian tube dysfunction, 6 cases caused by upper respiratory tract infection aviation otitis media, 12 cases were caused by nasal and nasopharyngeal lesions aviation otitis media.Conclusion Through summary analysis of the diagnostic data, aviation otitis media of the upper respiratory tract infection were the major pathogenic factors, nasopharyngeal lesions and the decrease of the aircraft speed, etc.%目的 探讨分析航空性中耳炎的临床症状.方法 对2010年1月~ 2015年1月来我院就诊的12名空勤人员和8名旅客的诊断资料进行回顾性分析,通过对临床资料总结研究,了解航空性中耳炎的致病因素及临床症状.结果 20个病例中,初步诊断为2例因咽鼓管功能障碍导致航空性中耳炎,6例因上呼吸道感染导致航空性中耳炎,12例因鼻腔与鼻咽部病变导致航空性中耳炎.结论 通过对诊断资料的总结分析,航空性中耳炎的致病因素主要有上呼吸道感染、鼻咽部病变、飞机下降速度等.

  12. Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations

    Energy Technology Data Exchange (ETDEWEB)

    Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

    2014-11-27

    Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

  13. 75 FR 43105 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-07-23

    ... weaken the structure, compromising the fuselage structural integrity. The proposed AD would require... provide. We will also post a report summarizing each substantive verbal contact we receive about this... could locally weaken the structure, compromising the fuselage structural integrity. This AD requires...

  14. Optimization of Simplex Atomizer Inlet Port Configuration through Computational Fluid Dynamics and Experimental Study for Aero-Gas Turbine Applications

    Science.gov (United States)

    Marudhappan, Raja; Chandrasekhar, Udayagiri; Hemachandra Reddy, Koni

    2017-10-01

    The design of plain orifice simplex atomizer for use in the annular combustion system of 1100 kW turbo shaft engine is optimized. The discrete flow field of jet fuel inside the swirl chamber of the atomizer and up to 1.0 mm downstream of the atomizer exit are simulated using commercial Computational Fluid Dynamics (CFD) software. The Euler-Euler multiphase model is used to solve two sets of momentum equations for liquid and gaseous phases and the volume fraction of each phase is tracked throughout the computational domain. The atomizer design is optimized after performing several 2D axis symmetric analyses with swirl and the optimized inlet port design parameters are used for 3D simulation. The Volume Of Fluid (VOF) multiphase model is used in the simulation. The orifice exit diameter is 0.6 mm. The atomizer is fabricated with the optimized geometric parameters. The performance of the atomizer is tested in the laboratory. The experimental observations are compared with the results obtained from 2D and 3D CFD simulations. The simulated velocity components, pressure field, streamlines and air core dynamics along the atomizer axis are compared to previous research works and found satisfactory. The work has led to a novel approach in the design of pressure swirl atomizer.

  15. Nonlinear Parameter-Varying AeroServoElastic Reduced Order Model for Aerostructural Sensing and Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the project is to develop reliable reduced order modeling technologies to automatically generate nonlinear, parameter-varying (PV),...

  16. 发动机修理技术的研发现状%New Progress for Aero-Engine Repair

    Institute of Scientific and Technical Information of China (English)

    张小伟

    2014-01-01

    在飞机发动机变得日益高效的同时,所使用的材料和制造工艺也变得更复杂、更先进。维修企业在开展修理业务的同时也需要自行投资研发新的修理技术。

  17. Strouhal number dependency of the aero-acoustic response of wall perforations under combined grazing-bias flow

    Science.gov (United States)

    Moers, E. M. T.; Tonon, D.; Hirschberg, A.

    2017-02-01

    The influence of low Mach number grazing-bias flow on the linear acoustic response of slit shaped wall perforations is determined in terms of a dimensionless acoustical impedance for Strouhal numbers based on the perforation width of order unity. The influence of edge geometries is studied by experiments. In particular, slanted slits under an angle of 30° with respect to the grazing flow direction are considered. Sound production, i.e. whistling potentiality corresponding to a negative real part of the impedance, is observed for various geometries and flow conditions. Sound production restricts the largest perforation size which can be used in practice for acoustical liners. Whistling in the limit cases of purely bias and purely grazing flows can be explained qualitatively in terms of Vortex Sound Theory. For combined bias/grazing flow, most of the oscillations in the impedance as a function of the Strouhal number are related to these limit behaviours. A configuration with thin sharp edges both upstream and downstream corresponds to commonly used theoretical models assuming an infinite thin wall. This configuration displays a behaviour drastically different from a more realistic perforation geometry with sharp square edges.

  18. 75 FR 50850 - Special Conditions: AeroMech, Incorporated; Hawker Beechcraft Corporation, Model B200 and Other...

    Science.gov (United States)

    2010-08-18

    ... likely result in explosion, fire, or both. Certain types of Li-ion batteries pose a potential safety... explosion or fire in the event of those failures. (2) Li-ion batteries must be designed to preclude the... structure or essential systems that may be caused by the maximum amount of heat the battery can...

  19. A parametric study on supersonic/hypersonic flutter behavior of aero-thermo-elastic geometrically imperfect curved skin panel

    NARCIS (Netherlands)

    Abbas, L.K.; Rui, X.; Marzocca, P.; Abdalla, M.; De Breuker, R.

    2011-01-01

    In this paper, the effect of the system parameters on the flutter of a curved skin panel forced by a supersonic/hypersonic unsteady flow is numerically investigated. The aeroelastic model investigated includes the third-order piston theory aerodynamics for modeling the flow-induced forces and the V

  20. Numerical simulation of weld tab length influence on welding residual stress and distortion of aero-engine disk

    Institute of Scientific and Technical Information of China (English)

    Xue-qiu ZHANG; Jian-guo YANG; Xue-song LIU; Xu-hui CHEN; Hong-yuan FANG; Shen QU

    2009-01-01

    In order to control the welding residual stress and distortion to the greatest extent, based on the MSC. MARC software platform and adopting the impending critical value methods gradually, the welding residual stress and distortion are calculated through varying the weld tab length values. The results show that different weld tab lengths only have a slight effect on welding residual stress but a significant effect on welding distortion. According to the calculation results with different weld tab lengths, the critical length value for the 100 mm-length TC4 alloy weld for electron beam welding of an integral disk should be 50 mm or so.

  1. Enzymatic Synthesis of 5-Fluorouridine with Enterobacter Aero-genes%酶法合成5-氟尿苷

    Institute of Scientific and Technical Information of China (English)

    雷霆; 周长林; 窦洁; 吴梧桐

    2000-01-01

    采用产气肠杆菌(Enterobacter aerogenes) CPU 7856变异株的游离细胞,利用其中的嘧啶核苷磷酸化酶(Uridine Phosphorylase)通过碱基交换进行酶法合成目的物.试验以30mmol/L尿苷(UR),30mmol/L 5-氟尿嘧啶( FU),30mmol/L磷酸盐缓冲液(pH7.8)的混合物加入10%的产气肠杆菌湿菌体反应3h,底物UR的转化率可达50%.

  2. 75 FR 43095 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A. Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-07-23

    ... INDUSTRIES S.p.A. Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... failure of engine oil dipsticks, installed on Pratt & Whitney Canada (P&WC) PT6A66 and PT6A66B engines, were detected on P.180 aeroplanes; such failures, due to moisture penetration into the dipstick...

  3. 75 FR 7409 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-02-19

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of..., Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday... 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD,...

  4. 76 FR 36980 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2011-06-24

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the.... BILLING CODE 4910-13-P...

  5. 76 FR 4056 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2011-01-24

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), DOT. ACTION... 5 p.m., Monday through Friday, except Federal holidays. Examining the AD Docket You may examine the... Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket...

  6. 75 FR 43101 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-07-23

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except....regulations.gov ; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday...

  7. 75 FR 63060 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A. Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-10-14

    ... INDUSTRIES S.p.A. Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of..., installed on Pratt & Whitney Canada (P&WC) PT6A66 and PT6A66B engines, were detected on P.180 aeroplanes... & Whitney Canada (P&WC) PT6A66 and PT6A66B engines, were detected on P.180 aeroplanes; such failures, due...

  8. 75 FR 63062 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-10-14

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... Assembly (P/N 80-337284- 001), which allows better clearances and removes the problem of potential interference. PAI issued SB 80-0175 Revision 1, limiting the applicability to aeroplanes with the old...

  9. 75 FR 47734 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2010-08-09

    ... Industries S.p.A. Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of...-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through... http://www.regulations.gov ; or in person at the Docket Management Facility between 9 a.m. and 5...

  10. 76 FR 54403 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Science.gov (United States)

    2011-09-01

    ... INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes AGENCY: Federal Aviation Administration (FAA), Department of... sleeves (part number (P/N) 114146681), which were installed in some Main Landing Gear (MLG) actuators, had... Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday,...

  11. Radiative forcing by aerosols as derived from the AeroCom present-day and pre-industrial simulations

    Directory of Open Access Journals (Sweden)

    M. Schulz

    2006-01-01

    Full Text Available Nine different global models with detailed aerosol modules have independently produced instantaneous direct radiative forcing due to anthropogenic aerosols. The anthropogenic impact is derived from the difference of two model simulations with prescribed aerosol emissions, one for present-day and one for pre-industrial conditions. The difference in the solar energy budget at the top of the atmosphere (ToA yields a new harmonized estimate for the aerosol direct radiative forcing (RF under all-sky conditions. On a global annual basis RF is −0.22 Wm−2, ranging from +0.04 to −0.41 Wm−2, with a standard deviation of ±0.16 Wm−2. Anthropogenic nitrate and dust are not included in this estimate. No model shows a significant positive all-sky RF. The corresponding clear-sky RF is −0.68 Wm−2. The cloud-sky RF was derived based on all-sky and clear-sky RF and modelled cloud cover. It was significantly different from zero and ranged between −0.16 and +0.34 Wm−2. A sensitivity analysis shows that the total aerosol RF is influenced by considerable diversity in simulated residence times, mass extinction coefficients and most importantly forcing efficiencies (forcing per unit optical depth. The clear-sky forcing efficiency (forcing per unit optical depth has diversity comparable to that for the all-sky/ clear-sky forcing ratio. While the diversity in clear-sky forcing efficiency is impacted by factors such as aerosol absorption, size, and surface albedo, we can show that the all-sky/clear-sky forcing ratio is important because all-sky forcing estimates require proper representation of cloud fields and the correct relative altitude placement between absorbing aerosol and clouds. The analysis of the sulphate RF shows that long sulphate residence times are compensated by low mass extinction coefficients and vice versa. This is explained by more sulphate particle humidity growth and thus higher extinction in those models where short-lived sulphate is present at lower altitude and vice versa. Solar atmospheric forcing within the atmospheric column is estimated at +0.82±0.17 Wm−2. The local annual average maxima of atmospheric forcing exceed +5 Wm−2 confirming the regional character of aerosol impacts on climate. The annual average surface forcing is −1.02±0.23 Wm−2. With the current uncertainties in the modelling of the radiative forcing due to the direct aerosol effect we show here that an estimate from one model is not sufficient but a combination of several model estimates is necessary to provide a mean and to explore the uncertainty.

  12. Intercomparison and evaluation of global aerosol microphysical properties among AeroCom models of a range of complexity

    Directory of Open Access Journals (Sweden)

    G. W. Mann

    2014-05-01

    Full Text Available Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical properties and cloud condensation nuclei (CCN concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study examines the global variation in particle size distribution simulated by 12 global aerosol microphysics models to quantify model diversity and to identify any common biases against observations. Evaluation against size distribution measurements from a new European network of aerosol supersites shows that the mean model agrees quite well with the observations at many sites on the annual mean, but there are some seasonal biases common to many sites. In particular, at many of these European sites, the accumulation mode number concentration is biased low during winter and Aitken mode concentrations tend to be overestimated in winter and underestimated in summer. At high northern latitudes, the models strongly underpredict Aitken and accumulation particle concentrations compared to the measurements, consistent with previous studies that have highlighted the poor performance of global aerosol models in the Arctic. In the marine boundary layer, the models capture the observed meridional variation in the size distribution, which is dominated by the Aitken mode at high latitudes, with an increasing concentration of accumulation particles with decreasing latitude. Considering vertical profiles, the models reproduce the observed peak in total particle concentrations in the upper troposphere due to new particle formation, although modelled peak concentrations tend to be biased high over Europe. Overall, the multi-model-mean data set simulates the global variation of the particle size distribution with a good degree of skill, suggesting that most of the individual global aerosol microphysics models are performing well, although the large model diversity indicates that some models are in poor agreement with the observations. Further work is required to better constrain size-resolved primary and secondary particle number sources, and an improved understanding of nucleation and growth (e.g. the role of nitrate and secondary organics will improve the fidelity of simulated particle size distributions.

  13. Convergence Analysis of the Numerical Solution for Cathode Design of Aero-engine Blades in Electrochemical Machining

    Institute of Scientific and Technical Information of China (English)

    Li Zhiyong; Niu Zongwei

    2007-01-01

    As a main difficult problem encountered in electrochemical machining (ECM), the cathode design is tackled, at present, with various numerical analysis methods such as finite difference, finite element and boundary element methods. Among them, the finite element method presents more flexibility to deal with the irregularly shaped workpieces. However, it is very difficult to ensure the convergence of finite element numerical approach. This paper proposes an accurate model and a finite element numerical approach of cathode design based on the potential distribution in inter-electrode gap. In order to ensure the convergence of finite element numerical approach and increase the accuracy in cathode design, the cathode shape should be iterated to eliminate the design errors in computational process. Several experiments are conducted to verify the macbining accuracy of the designed cathode. The experimental results have proven perfect convergence and good computing accuracy of the proposed finite element numerical approach by the high surface quality and dimensional accuracy of the machined blades.

  14. Numerical modeling of separated flows at moderate Reynolds numbers appropriate for turbine blades and unmanned aero vehicles

    Science.gov (United States)

    Castiglioni, Giacomo

    Flows over airfoils and blades in rotating machinery, for unmanned and micro-aerial vehicles, wind turbines, and propellers consist of a laminar boundary layer near the leading edge that is often followed by a laminar separation bubble and transition to turbulence further downstream. Typical Reynolds averaged Navier-Stokes turbulence models are inadequate for such flows. Direct numerical simulation is the most reliable, but is also the most computationally expensive alternative. This work assesses the capability of immersed boundary methods and large eddy simulations to reduce the computational requirements for such flows and still provide high quality results. Two-dimensional and three-dimensional simulations of a laminar separation bubble on a NACA-0012 airfoil at Rec = 5x104 and at 5° of incidence have been performed with an immersed boundary code and a commercial code using body fitted grids. Several sub-grid scale models have been implemented in both codes and their performance evaluated. For the two-dimensional simulations with the immersed boundary method the results show good agreement with the direct numerical simulation benchmark data for the pressure coefficient Cp and the friction coefficient Cf, but only when using dissipative numerical schemes. There is evidence that this behavior can be attributed to the ability of dissipative schemes to damp numerical noise coming from the immersed boundary. For the three-dimensional simulations the results show a good prediction of the separation point, but an inaccurate prediction of the reattachment point unless full direct numerical simulation resolution is used. The commercial code shows good agreement with the direct numerical simulation benchmark data in both two and three-dimensional simulations, but the presence of significant, unquantified numerical dissipation prevents a conclusive assessment of the actual prediction capabilities of very coarse large eddy simulations with low order schemes in general cases. Additionally, a two-dimensional sweep of angles of attack from 0° to 5° is performed showing a qualitative prediction of the jump in lift and drag coefficients due to the appearance of the laminar separation bubble. The numerical dissipation inhibits the predictive capabilities of large eddy simulations whenever it is of the same order of magnitude or larger than the sub-grid scale dissipation. The need to estimate the numerical dissipation is most pressing for low-order methods employed by commercial computational fluid dynamics codes. Following the recent work of Schranner et al., the equations and procedure for estimating the numerical dissipation rate and the numerical viscosity in a commercial code are presented. The method allows for the computation of the numerical dissipation rate and numerical viscosity in the physical space for arbitrary sub-domains in a self-consistent way, using only information provided by the code in question. The method is first tested for a three-dimensional Taylor-Green vortex flow in a simple cubic domain and compared with benchmark results obtained using an accurate, incompressible spectral solver. Afterwards the same procedure is applied for the first time to a realistic flow configuration, specifically to the above discussed laminar separation bubble flow over a NACA 0012 airfoil. The method appears to be quite robust and its application reveals that for the code and the flow in question the numerical dissipation can be significantly larger than the viscous dissipation or the dissipation of the classical Smagorinsky sub-grid scale model, confirming the previously qualitative finding.

  15. 75 FR 33553 - Special Conditions: AeroMech, Incorporated; Hawker Beechcraft Corporation, Model B200 and Other...

    Science.gov (United States)

    2010-06-14

    ... batteries in general aviation airplanes, including Sec. 23.1353 were derived from Civil Air Regulations (CAR... affect safety of the ] battery installation and the reliability of the electrical power supply on the...); Installation of MD835 Lithium Ion Battery AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of...

  16. Aero-acoustic simulation of a subsonic hot jet; Simulation aeroacoustique d'un jet chaud subsonique

    Energy Technology Data Exchange (ETDEWEB)

    Biancherin, A.; Rahier, G.; Prieur, J.; Vuillot, F.; Lupoglazoff, N.

    2002-07-01

    This paper presents a numerical simulation of subsonic a hot jet (M 0,7) and its acoustic analysis. The MSD code of the ONERA is used to resolve the Navier-Stokes equations. A detailed study, parametric and theoretical is realized to analyze the influence of the formulation, the position, the part and the nature of the control surface on the acoustic calculation results. The acoustic predictions in far field are compared to measures realized by the ONERA in the anechoic CEPRA 19 wind tunnel. (A.L.B.)

  17. Surmanuhtlus kõrgeima võimaliku karistusmäärana : [bakalaureusetöö] / Katrin Roosmaa ; Tartu Ülikool, õigusteaduskond ; juhendaja: Silvia Kaugia

    Index Scriptorium Estoniae

    Roosmaa, Katrin, 1984-

    2007-01-01

    Surmanuhtluse olemus ja selle karistusliigiga sanktsioneeritud teod Eestis lähiminevikus, surmanuhtluse määramine ja täideviimine kuni 1998. a.-ni, surmanuhtluse kaotamise direktiiv ning seda toetavad ja mittetoetavad riigid, levinumad poolt- ja vastuargumendid, Eesti elanikkonna suhtumine

  18. "Ega Kruuda pole koi poiss old!" / Madis Jürgen

    Index Scriptorium Estoniae

    Jürgen, Madis, 1962-

    2007-01-01

    Mitmed ärimees Oliver Kruuda naabrid Helbe tänavas toetavad ärimehe tööd võsa muutmisel haljasalaks ning paluvad keskkonnaministeeriumile, Tallinna keskkonnaametile ja Nõmme linnaosa valitsusele saadetud kirjas abi O. Kruuda korrastustööde jätkamiseks Helbe tänava piirkonnas. Linnaosa vanema Rainer Vakra arvamus

  19. Saksamaal võidab toetust utoopia : raha jagamine ilma tööta / Külli-Riin Tigasson

    Index Scriptorium Estoniae

    Tigasson, Külli-Riin, 1975-

    2007-01-01

    Saksamaal toetavad mitmed poliitikud utoopilist ideed: ära kaotada kõik sotsiaaltoetused ning asendada need 700-1500-eurose riikliku kuusissetulekuga, mida makstaks kõigile Saksa kodanikele, sõltumata sellest, kas nad töötavad või mitte. Vt. samas: Kas Milton Friedman eksis?

  20. Tallinna lennujaam võib siiski saada Lennart Meri nime / Anneli Ammas

    Index Scriptorium Estoniae

    Ammas, Anneli, 1962-

    2007-01-01

    Mart Laar, Indrek Neivelt ja Urmas Paet toetavad ideed anda Tallinna lennujaamale Lennart Meri nimi. President Lennart Meri poja Mart Meri arvamus. Eelseisvast Lennart Merile pühendatud rahvusvahelisest julgeolekukonverentsist. Lisad: Esimene Lennart Meri mälestuskonverents; Ausamba idee ummikus

  1. Res Publica nõuab rea võimulubaduste täitmist / Rasmus Kagge

    Index Scriptorium Estoniae

    Kagge, Rasmus, 1977-

    2005-01-01

    Res Publica lubas koalitsioonipartneritele mitte minna koalitsioonileppe kallale, kui nad toetavad toppama jäänud lubaduste täitmist - haridusreformi, presidendi otsevalimiste seadustamist, riigikontrollile ka omavalitsuste kontrollimiseks õiguse andmist ja lapsevanema tulumaksuvaba miinimumi kahekordistamist alates pere teisest lapsest. Lisa: Võimuliitlaste soovid

  2. Valimistel põrunud Rootsi feministid loobuvad parteist / Triin Oppi

    Index Scriptorium Estoniae

    Oppi, Triin

    2007-01-01

    Ilmunud ka: Postimees : na russkom jazõke, 22. veebr. 2007, lk. 9. Rootsi 2006. aasta parlamendivalimistel sai feministlik partei Feministlik Initsiatiiv kõigest 0,68 % häältest ja keskendub nüüd rahvaliikumisena teavitustööle. Lisa: Tulemused. Vt. samas: Rootslased toetavad opositsiooni

  3. Märgakem probleemidega last! / Kristjan Paas, Kaire Tamm

    Index Scriptorium Estoniae

    Paas, Kristjan

    2003-01-01

    2002. a. viis Riigikontroll läbi auditi - koolides ja alaealiste komisjonides läbi viidud küsitlusuuringus selgitati koolikohustuse täitmisega seotud küsimusi, õpilaste koolist puudumist, klassikursuse kordamist. Koolikohustuse mittetäitmise põhjused, täitmist toetavad võimalused.

  4. IMF says to stay the course

    Index Scriptorium Estoniae

    2010-01-01

    Rahvusvaheline Valuutafond ja Euroopa Komisjon toetavad praegust Läti majanduskurssi. IMF-i kirjast, mis käsitleb lati devalveerimise teemat ja mis on väidetavalt võltsing. Läti keskpanga juht Ilmars Rimsevics leiab, et devalvatsioon oleks riigile väga kahjulik

  5. Teadlased katsetavad ettevõtlusega / Väinu Rozental

    Index Scriptorium Estoniae

    Rozental, Väinu, 1957-

    2004-01-01

    Tartu Ülikoolist välja kasvanud teadusmahukad spin-off-ettevõtted on üldjuhul edukad vaid siis, kui firmat juhib majandusharidusega tegevjuht, mitte teadlane. Diagramm. Vt. samas: Ärimehed toetavad meditsiinitehnikat. Tartu Ülikoolist võrsunud teadusmahukad ettevõtted

  6. Sakslased tulevad! Ärevad ajad Tallinnas Von Krahli Teatris

    Index Scriptorium Estoniae

    2001-01-01

    Von Krahli Teater ja Showcase Beat Le Mot valmistuvad oma esimeseks koostööprojektiks - lavastuseks "Pirates", kus osalevad mõlema teatri näitlejad ja tehnikud. Ühisprojekti toetavad Goethe Instituut, Hamburgi Linnavalitsus ja Eesti Kultuurkapital

  7. IT-firmad pääsevad pooleks aastaks Silicon Valleysse / Holger Roonemaa

    Index Scriptorium Estoniae

    Roonemaa, Holger

    2010-01-01

    Tehnopol ja EAS toetavad nn. start-up-firmade saatmist pooleks aastaks USA-sse Silicon Valleysse kogemusi omandama, programm on mõeldud eelkõige neile ettevõtetele, kel on oma toode või teenus valmis ja kes soovivad sellega maailmaturule minna

  8. Roheline plahvatus / Neeme Raud

    Index Scriptorium Estoniae

    Raud, Neeme, 1969-

    2007-01-01

    USA-s on populaarseks saamas roheline mõtteviis, mida jõudsalt toetavad ka osariikide ja suurlinna juhid. Kõige enam arendatakse säästlikku tehnoloogiat Silicon Valleys. Tabel: Investorite lemmikud. Vt. samas: Investeeringud rohelisse tehnoloogiasse; Prügimäed parkideks

  9. Eesti transpordi infrastruktuuri ootavad suured toetused / Tanel Tang

    Index Scriptorium Estoniae

    Tang, Tanel

    2003-01-01

    EL-iga liitumisel avanevad Eestile Euroopa Regionaalarengu fond (ERDF) ja Ühtekuuluvusfond, mis tähendab transpordisektorile miljardite kroonide suurust abi maanteede, raudteede, lennujaamade ning sadamate ehitamiseks ja rekonstrueerimiseks. Vt. samas: Eestile tulnud abi PHARE ja ISPA fondist ; Ühtekuuluvusfond ja Euroopa regionaalarengu fond (ERDF) toetavad Eestit miljonite kroonidega. Diagramm: EL-i abi Eesti transpordisektorile

  10. Märgakem probleemidega last! / Kristjan Paas, Kaire Tamm

    Index Scriptorium Estoniae

    Paas, Kristjan

    2003-01-01

    2002. a. viis Riigikontroll läbi auditi - koolides ja alaealiste komisjonides läbi viidud küsitlusuuringus selgitati koolikohustuse täitmisega seotud küsimusi, õpilaste koolist puudumist, klassikursuse kordamist. Koolikohustuse mittetäitmise põhjused, täitmist toetavad võimalused.

  11. Bush skazal ne sovsem to, tshto skazal

    Index Scriptorium Estoniae

    2006-01-01

    USA abivälisminister Euroopa ja Euraasia küsimustes Daniel Fried teatas, et NATO riigid toetavad Gruusia, Moldova ja Aserbaidžaani territoriaalset terviklikkust, kuid ei luba neil seda taastada relva abil. Abiminister selgitab, mida pidas USA president George W. Bush silmas, kui ta avaldas Riia tippkohtumisel toetust Gruusiale tema püüdlustes liituda NATO-ga

  12. Bush skazal ne sovsem to, tshto skazal

    Index Scriptorium Estoniae

    2006-01-01

    USA abivälisminister Euroopa ja Euraasia küsimustes Daniel Fried teatas, et NATO riigid toetavad Gruusia, Moldova ja Aserbaidžaani territoriaalset terviklikkust, kuid ei luba neil seda taastada relva abil. Abiminister selgitab, mida pidas USA president George W. Bush silmas, kui ta avaldas Riia tippkohtumisel toetust Gruusiale tema püüdlustes liituda NATO-ga

  13. Sotsiaalmajandus ja sotsiaalettevõtlus / Leonora Kraus

    Index Scriptorium Estoniae

    Kraus, Leonora

    2007-01-01

    EQUAL programmist ja HAPECO projektist, mis toetavad sotsiaalmajanduse ja sotsiaalettevõtluse arendamist Euroopa Liidus. Vt. samas: Annely T. Kattel. President tunnustas sotsiaalettevõtlust. Hiiumaa visiidi käigus külastas president T. H. Ilves MTÜ SIPEKO tegevustuba

  14. Eesti transpordi infrastruktuuri ootavad suured toetused / Tanel Tang

    Index Scriptorium Estoniae

    Tang, Tanel

    2003-01-01

    EL-iga liitumisel avanevad Eestile Euroopa Regionaalarengu fond (ERDF) ja Ühtekuuluvusfond, mis tähendab transpordisektorile miljardite kroonide suurust abi maanteede, raudteede, lennujaamade ning sadamate ehitamiseks ja rekonstrueerimiseks. Vt. samas: Eestile tulnud abi PHARE ja ISPA fondist ; Ühtekuuluvusfond ja Euroopa regionaalarengu fond (ERDF) toetavad Eestit miljonite kroonidega. Diagramm: EL-i abi Eesti transpordisektorile

  15. IT-firmad pääsevad pooleks aastaks Silicon Valleysse / Holger Roonemaa

    Index Scriptorium Estoniae

    Roonemaa, Holger

    2010-01-01

    Tehnopol ja EAS toetavad nn. start-up-firmade saatmist pooleks aastaks USA-sse Silicon Valleysse kogemusi omandama, programm on mõeldud eelkõige neile ettevõtetele, kel on oma toode või teenus valmis ja kes soovivad sellega maailmaturule minna

  16. Krizis islama mozhet porodit novõhh monstrov / Vladimir Rodin

    Index Scriptorium Estoniae

    Rodin, Vladimir

    2004-01-01

    Autor juhib tähelepanu nende terrorirühmituste hulga kasvule, mille liikmed ei ole islamistid. Tema sõnul ei ole olemas ühtse eesmärgiga rahvusvahelist terrorismi, al-Qaida aga pole nii võimas struktuur, nagu seda kujutatakse. Samas toetavad terroriorganisatsioonide eluvõimelisust USA-vastased meeleolud

  17. Roheline plahvatus / Neeme Raud

    Index Scriptorium Estoniae

    Raud, Neeme, 1969-

    2007-01-01

    USA-s on populaarseks saamas roheline mõtteviis, mida jõudsalt toetavad ka osariikide ja suurlinna juhid. Kõige enam arendatakse säästlikku tehnoloogiat Silicon Valleys. Tabel: Investorite lemmikud. Vt. samas: Investeeringud rohelisse tehnoloogiasse; Prügimäed parkideks

  18. Reinsalu: Maripuu, pane rahakott nõueteks valmis / Mirko Ojakivi ; kommenteerinud Eiki Nestor, Rauno Veri ja Taavi Rõivas

    Index Scriptorium Estoniae

    Ojakivi, Mirko

    2009-01-01

    Riigikogu põhiseaduskomisjoni liikme Urmas Reinsalu arvates tuleks puudega inimeste toetuse viibimisest tekitatud kahjud sotsiaalministeeriumil kindlasti hüvitada. Sotsiaalministeerium kavatseb arutada puudega inimeste katusorganisatsioonidega võimalikku kahju kompenseerimist. Eiki Nestor, Rauno Veri ja Taavi Rõivas vastavad küsimusele, kas nad toetavad umbusaldusavaldust Maret Maripuule

  19. Sotsiaalmajandus ja sotsiaalettevõtlus / Leonora Kraus

    Index Scriptorium Estoniae

    Kraus, Leonora

    2007-01-01

    EQUAL programmist ja HAPECO projektist, mis toetavad sotsiaalmajanduse ja sotsiaalettevõtluse arendamist Euroopa Liidus. Vt. samas: Annely T. Kattel. President tunnustas sotsiaalettevõtlust. Hiiumaa visiidi käigus külastas president T. H. Ilves MTÜ SIPEKO tegevustuba

  20. Ilvese konkurentide pink püsib tühjana / Argo Ideon

    Index Scriptorium Estoniae

    Ideon, Argo, 1966-

    2011-01-01

    21. mail Tallinnas toimuval Isamaa ja Res Publica Liidu volikogul vastab erakonna küsimustele 2011. aasta presidendivalimistel kandideeriv praegune president Toomas Hendrik Ilves, keda toetavad Reformierakond ja Sotsiaaldemokraatlik Erakond. Keskerakonna valikutest. Vt. ka juhtkiri lk. 2: Kampaaniata presidendiks. Lk. 2 ka Urmas Nemvaltsi karikatuur