DOCSLIB.ORG

NREL Airfoil Families for Hawts

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
NREL Airfoil Families for Hawts January 1995 • NRELfTP-442-7109 NREL Airfoil F es forHAWTs J. L. Tangier D. M. Somers �L.•�I,E!.� �.J' National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 A national laboratory of the U.S. Department of Energy Managed by Midwest Research Institute for the U.S. Department of Energy under Contract No. DE-AC36-83CH10093 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, orassumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Available to DOE and DOE contractors from: Office of Scientific and Technical Information (OSTI) P.O. Box62 Oak Ridge, TN 37831 Prices available by calling {4 23) 576-8401 Available to the public from: National Technical Information Service {NTIS) U.S. Department of Commerce 5285 Port Royal Road Springfield, VA 22161 (703) 487 -4650 #. t.� Printed on paper containing at least 50% wastepaper, including 10% postconsumer waste NRELAirfoil Families for HAWTs J. L. Tangier National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 D. M. Somers Airfoils Incorporated 601 Cricklewood Drive State College, Pennsylvania 16803-2111 ABSTRACT The development of special-purpose airfoils for horizontal-axis wind turbines (HAWT�) began in 1984 as a joint effort between the National Renewable Energy Laboratory (NREL), formerly the Solar Energy Research Institute (SERI), and Airfoils, Incorporated. Since that time seven airfoil families have been designed for various size rotors using the Eppler Airfoil Design and Analysis Code. A general performancerequirement of thenew airfoilfamilies is thatthey exhibit a maximum 1iftcoefficient ( '1,rnaJ which is relatively insensitiveto roughness effects. Theairfoil families address the needs of stall-regulated, variable-pitch, andvariable-rpm wind turbines. For stall-regulated rotors, betterpeak-power controlis achieved through thedesign of tip airfoils that restrain themaximum 1iftcoefficient. Restrainedmaximum coefficient 1ift allows the useof more swept disc area for a given generator size. Also, for stall-regulated rotors, tip airfoils with high thickness are used to accommodate overspeed control devices. For variable-pitch and variable-rpm rotors, tip airfoils having a highmaximum lift coefficientlend themselves to lightweight blades with low solidity.Tip airfoils having low thickness result in less drag for blades having full-span pitch control Annual energy improvements from the NREL airfoil families are projected to be 23% to 35% for stall­ regulatedturbines, 8% to 20% for variable-pitchturbines, and8% to 10% for variable-rpmturbines. Theimprovement for stall-regulatedturbines has been verified in fieldtests. INTRODUCTION Over the past decade, commonly used airfoilfamilies for horizontal axis wind turbines (HAWTs) have includedthe NACA 44XX,NACA 23XXX,NACA 63XXX, andNASA LS( 1) series airfoils. Allthese airfoils suffer noticeable performancedegradation fromroughness effects resulting from leading-edge contamination. Annual energy losses due to leading-edge roughness are greatest for stall-regulated rotors. The loss is largelyproportional to thereduction in maximumlift coefficient ( <1,maJalong the blade. High blade-root twist helps reduce the loss by keeping the blade's angle-of. attack distnoutionaway from stallwhich delays the onset of '1.max. Roughness also degrades.the.. airfoil's1ift-curve slope andincreases the profile drag which contnoutesto further losses. For stall- 1 regulated rotors, whose angleof attack distributionincreases with wind speed, theannual energy loss istypic ally20% to 30%. Variable-pitchtoward stall would result in similar roughness losses as fixed­ pitch, stall-regulation,while variable-pitch toward feather would decrease the loss to around 10% at the expenseof the rotor being susceptibleto power spikesin turbulent highwinds. For variable-rpm rotors operating at constant tip-speed ratio and angle of attack distnbution, the loss is minimal at around5% to 10%. To minimize the energy losses due to roughness effects and to develop special­ pmpose airfoilsfor HAWTs, the National RenewableEnergy Laboratory (NREL ), formerlythe Solar EnergyResearch Institute (SERI), andAirfoils Inc. began a joint airfoil development effort in1984. Results of thiseffort are reported in References 1 and2. Estimated annual energyimprov ements and thecomp onent improvementsfrom the NREL airfoils for stall-regulated , variable-pitch, and variable­ rpmrotors are shownin Table 1. Table 1. Estimated Annual Energy Improvements from NREL Airfoil Families Roughness Correct Total Turbine Type Insensitive c�,mn Reynolds Low Tip c�,mn Improvement Number Stall-Regulated 10% to 15% 3% to 5% 10% to 15% 23% to 35% Variable-Pitch 5% to 15% 3% to 5% --- 8% to 20% Variable-RPM 5% 3% to 5% --- 8% to 10% By using the NREL airfoils, which are specifically designed for HAWTs, the annual energy production loss due to airfoilroughness effects can be cut in half relativeto previously used aircraft airfoils. Optimizing anairfoil's performance characteristics for the appropriate Reynolds number and thickness provides additional performance enhancement in the range of 3% to 5%. Aircraft airfoils used on wind-turbineblades are often used at a lower Reynolds number than that intended by their designers. In addition, the airfoils are often scaled to a greater thickness which often leads to undesirable performance characteristics. The performance characteristics of the NACA 23XX:X seriesof airfoils,for example, deteriorate quiterapidly with increasing airfoilthickness. Thisproblem is further compounded in the blade root area by combining a low Reynolds number with high thickness. Such a combination makes it difficultto achieve good airfoil performance characteristics. For stall-regulated rotors, further performance enhancement is achieved by usingblade tip airfoils withlow G,maxwhich helps controlpeak rotor power. Thisallows the use of 10% to 15% more swept rotor area for a givengenerator size. Desirable performancecharacteristics for wind-turbine airfoilsdepend on whether themachine is stall­ regulated, variable-pitch, or variable-rpm. For stall-regulated machines, restrained maximum lift coefficient inthe blade tip regionis desired to passivelycontrol peak rotor power. Thisfeature will also benefit machines withvariable-pitch blades that pitchtoward Stallto control peak power, such as the NedWind 500 kW. Variablepitch machinesthat pitch toward featherto control peak power have the option of using tip airfoils with either highor low maximum lift coefficient depend.i¥g,,�n whether machinethe is designedto operate at high or low rpm. However, pitching toward feather resultsin excessive turbulence-induced peak-power spikes (Reference 3) that create operation and 2 maintainanceproblems. Power spikesare effectivelyeliminated through variable-rotor-rpm operation which absorbs the power spikeswith an increase in rpm The sevenNREL airfoil families,which include over twenty different airfoils, have been designed usingthe Eppler code (References 4 and5) to accommodate the unique operating. requirements of . stall-regulated, variable-pitch, and variable-rpmwind turbines. Most of the existingNREL airfoil familiesaddress the needs of stall-regulatedwind turbines. Efforts currently underway are focusing on tipairfoils for variable-rpmwind turbines. This paper provides a summary of the existingNREL airfoilfamilies and those curr entlybeing designed. NREL AIRFOIL FAMILIES Seven airfoilfamilies consisting of 23 airfoils have beendesigned for various size rotors since1984� The appropriate blade lengthand generator sizefor each airfoilfamily along with thecorresponding airfoilscomprising each familyfrom blade root to tip are shown in Table 2. The airfoil designations starting with theS80 1 andending with the S823 represent thenumerical order in. which the airfoils were designedbetween 1984 and 1993. The"A" designation stands for an improved version of an airfoilbased on wind-tunnel testresults for a similarairfoil. Thethree airfoils havingunderlined bold lettering have undergone comprehensive tests in the Delft University low-turbulence windtunnel. Testresults for these three airfoils are covered inReferences 6, 7, and 8. Five of the airfoil families are designated "thick" (16% to 21 %) to indicate that the tip-region airfoils are thick enough to accommodate overspeed-control aerodynamic devices andto reduce theblade weight. These"thick" airfoilfamilies lendthemselves to stall-regulatedwind turbines. Thetwo airfoilfamilies labeled "thin" (11% to 15%) are more suited to variable-pitch or variable-rpm turbines that use full-span blade. pitch. Greater thicknessis desired for the blade-root airfoilsto accommodate structural and dynamic considerations. The blade-root airfoil thickness falls in the range of 18%
Load more

Recommended publications
  • Technology for Pressure-Instrumented Thin Airfoil Models
    NASA-CR-3891 19850015493 NASA Contractor Report 3891 i 1 Technology for Pressure-Instrumented Thin Airfoil Models David A. Wigley ., ..... " .... _' /, !..... .,L_. '' CONTRACT NAS1-17571 MAY 1985 ( • " " c _J ._._l._,.. ¸_ - j, ;_.. , r_ '._:i , _ . ; . ,. NIA NASA Contractor Report 3891 Technology for Pressure-Instrumented Thin Airfoil Models David A. Wigley Applied Cryogenics & Materials Consultants, Inc. New Castle, Delaware Prepared for Langley Research Center under Contract NAS1-17571 N//X National Aeronautics and Space Administration Scientific and Technical InformationBranch 1985 Use of trademarks or names of manufacturers in this report does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the National Aeronautics and Space Administration. FINAL REPORT ON PHASE 1 OF NASA CONTRACT NASI-17571 "TECHNOLOGY FOR PRESSURE-INSTRUMENTED THIN AIRFOIL MODELS" PROJECT SU_IARY The objective of Phase 1 of this research was to identify, then select and evaluate, the most appropriate combination of materials and fabrication techniques required to produce a Pressure Instrumented Thin Airfoil model for testing in a Cryogenic wind Tunnel ( PITACT ). Particular attention was to be given to proving the feasability and reliability of each sub-stage and ensuring that they could be combined together without compromising the quality of the resultant segment or model. In order to provide a sharp focus for this research, experimental samples were to be fabricated as if they were trailing edge segments of a 6% thick supercritical airfoil, number 0631X7, scaled to a 325mm (13in.) chord, the maximum likely to be tested in the 13in. x 13in. adaptive wall test section of the 0.3m Transonic Cryogenic Tunnel at NASA Langley Research Center.
    [Show full text]
  • Aerodynamics of High-Performance Wing Sails
    Aerodynamics of High-Performance Wing Sails J. otto Scherer^ Some of tfie primary requirements for tiie design of wing sails are discussed. In particular, ttie requirements for maximizing thrust when sailing to windward and tacking downwind are presented. The results of water channel tests on six sail section shapes are also presented. These test results Include the data for the double-slotted flapped wing sail designed by David Hubbard for A. F. Dl Mauro's lYRU "C" class catamaran Patient Lady II. Introduction The propulsion system is probably the single most neglect­ ed area of yacht design. The conventional triangular "soft" sails, while simple, practical, and traditional, are a long way from being aerodynamically desirable. The aerodynamic driving force of the sails is, of course, just as large and just as important as the hydrodynamic resistance of the hull. Yet, designers will go to great lengths to fair hull lines and tank test hull shapes, while simply drawing a triangle on the plans to define the sails. There is no question in my mind that the application of the wealth of available airfoil technology will yield enormous gains in yacht performance when applied to sail design. Re­ cent years have seen the application of some of this technolo­ gy in the form of wing sails on the lYRU "C" class catamar­ ans. In this paper, I will review some of the aerodynamic re­ quirements of yacht sails which have led to the development of the wing sails. For purposes of discussion, we can divide sail require­ ments into three points of sailing: • Upwind and close reaching.
    [Show full text]
  • Active Control of Flow Over an Oscillating NACA 0012 Airfoil
    Active Control of Flow over an Oscillating NACA 0012 Airfoil Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By David Armando Castañeda Vergara, M.S., B.S. Graduate Program in Aeronautical and Astronautical Engineering The Ohio State University 2020 Dissertation Committee: Dr. Mo Samimy, Advisor Dr. Datta Gaitonde Dr. Jim Gregory Dr. Miguel Visbal Dr. Nathan Webb c Copyright by David Armando Castañeda Vergara 2020 Abstract Dynamic stall (DS) is a time-dependent flow separation and stall phenomenon that occurs due to unsteady motion of a lifting surface. When the motion is sufficiently rapid, the flow can remain attached well beyond the static stall angle of attack. The eventual stall and dynamic stall vortex formation, convection, and shedding processes introduce large unsteady aerodynamic loads (lift, drag, and moment) which are undesirable. Dynamic stall occurs in many applications, including rotorcraft, micro aerial vehicles (MAVs), and wind turbines. This phenomenon typically occurs in rotorcraft applications over the rotor at high forward flight speeds or during maneuvers with high load factors. The primary adverse characteristic of dynamic stall is the onset of high torsional and vibrational loads on the rotor due to the associated unsteady aerodynamic forces. Nanosecond Dielectric Barrier Discharge (NS-DBD) actuators are flow control devices which can excite natural instabilities in the flow. These actuators have demonstrated the ability to delay or mitigate dynamic stall. To study the effect of an NS-DBD actuator on DS, a preliminary proof-of-concept experiment was conducted. This experiment examined the control of DS over a NACA 0015 airfoil; however, the setup had significant limitations.
    [Show full text]
  • Development of Numerical Algorithm Based on a Modified Equation of Fluid Motion with Application to Turbomachinery Flow
    Development of Numerical Algorithm Based on a Modified Equation of Fluid Motion with Application to Turbomachinery Flow Von der Fakultät für Ingenieurwissenschaften, Abteilung Maschinenbau der Universität Duisburg-Essen zur Erlangung des akademischen Grades DOKTOR-INGENIEUR genehmigte Dissertation von Bo Wan aus Jiangsu, China Referent: Prof. Dr.-Ing. F.-K. Benra Korreferent: Prof. Dr. S. H. Sohrab Tag der mündlichen Prüfung: 03. September 2012 Abstract On the basis of the scale-invariant theory of statistical mechanics, Sohrab introduced a linear equation termed the “modified equation of fluid motion.” Preliminary investigations have shown that this modified equation can be extended to solve flow problems. Analytical solutions of basic flow problems were derived using this equation. In all cases the match between estimated and experimental data was good. These results stimulated further applications of this modified equation in the development of a CFD code to obtain numerical solutions of turbomachinery flow problems. In the present work, a novel numerical algorithm based on the aforementioned modified equation has been developed to solve turbomachinery flow problems. In order to avoid dealing with more technical conditions on the scale–invariant form of the energy equation, this investigation is restricted to incompressible flow. On the basis of the work done by Sohrab, the derivation process of the modified equation for incompressible flow is presented with more emphasis on its linear property as compared to the Navier–Stokes equation for incompressible flow. Furthermore, a detailed analysis of the present discretisation technique for the modified equation is performed. As compared with the Navier–Stokes equation, the numerical errors resulted from the discretisation of the modified equation, including the truncation and discretisation errors are discussed as well as the stability conditions.
    [Show full text]
  • Upwind Sail Aerodynamics : a RANS Numerical Investigation Validated with Wind Tunnel Pressure Measurements I.M Viola, Patrick Bot, M
    Upwind sail aerodynamics : A RANS numerical investigation validated with wind tunnel pressure measurements I.M Viola, Patrick Bot, M. Riotte To cite this version: I.M Viola, Patrick Bot, M. Riotte. Upwind sail aerodynamics : A RANS numerical investigation validated with wind tunnel pressure measurements. International Journal of Heat and Fluid Flow, Elsevier, 2012, 39, pp.90-101. 10.1016/j.ijheatfluidflow.2012.10.004. hal-01071323 HAL Id: hal-01071323 https://hal.archives-ouvertes.fr/hal-01071323 Submitted on 8 Oct 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. I.M. Viola, P. Bot, M. Riotte Upwind Sail Aerodynamics: a RANS numerical investigation validated with wind tunnel pressure measurements International Journal of Heat and Fluid Flow 39 (2013) 90–101 http://dx.doi.org/10.1016/j.ijheatfluidflow.2012.10.004 Keywords: sail aerodynamics, CFD, RANS, yacht, laminar separation bubble, viscous drag. Abstract The aerodynamics of a sailing yacht with different sail trims are presented, derived from simulations performed using Computational Fluid Dynamics. A Reynolds-averaged Navier- Stokes approach was used to model sixteen sail trims first tested in a wind tunnel, where the pressure distributions on the sails were measured.
    [Show full text]
  • Chapter 1: Introduction
    AIRFOIL OPTIMIZATION FOR MORPHING AIRCRAFT A Thesis Submitted to the Faculty of Purdue University by Howoong Namgoong In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2005 ii I dedicate this thesis to my father, Young Kyu Namgoong in heaven. iii ACKNOWLEDGMENTS Thanks to God for being my guidance of the journey of life. It has been a privilege to be a student of Drs. William A. Crossley and Anastasios S. Lyrintzis. I was able to open my eyes toward the world of design optimization and morphing aircraft with a tremendous help from Dr. Crossley. I learned great knowledge about aerodynamics and received precious advice from Dr. Lyrintzis. I will cherish and miss the moments that we met together for five years. Special thanks to my committee members, Dr. Scott D. King, Dr. Marc H. Williams and Dr. Terrence A. Weisshaar for their invaluable comments and lectures. I also thank to my colleagues and staffs in Purdue AAE department. This work was partially supported by the Air Force Research Laboratory, contract F33615-00-C-3051, and by a Purdue Research Foundation grant. I would like to share this great moment with my lovely wife, Miran who completes my life, and my beautiful son, Young who gives me another reason for living. I will not forget the support from my three sisters, Ran, Eun and Yoon and my brothers in law. I also like to thank my father and mother in law for their support and prayer. Lastly, my deep appreciation goes to my mother, Mal Soon Park who showed me the meaning of true love.
    [Show full text]
  • Airfoil Services
    Airfoil Services Airfoil Services has been jointly owned in equal shares by Lufthansa Technik and MTU Aero Engines since 2003. Part of Lufthansa Technik’s Engine Parts & Accessories Repair (EPAR) network, Airfoil Services specializes in the repair of blades from major aircraft engine manufacturers, including General Electric, CFM International and International Aero Engines. Service spectrum Located in Kota Damansara in Malaysia’s state of Selangor, Airfoil Services merges the leading-edge competencies of both parent companies. Airfoil Services is specializing in the repair of engine airfoils for low-pressure turbines and high-pressure compressors of CF6-50, CF6-80, CF34 engines as well as the CFM56 engine family Ȝ Kuala Lumpur and the V2500. The ultra-modern facility is equipped with state-of-the- art machinery and has installed the most advanced repair techniques such as the Advanced Recontouring Process (ARP), also offering special repair methods such as aluminide bronze coating and high velocity oxygen fuel spraying (HVOF). Organized according to the philosophy of lean production, the repairs follow the flow line principle. Key facts Customers benefit from optimized processes and very competitive turnaround times offered at cost-conscious conditions. At the same Founded 1991 time, the quality of work reflects the high standards of the two German Personnel 420 joint venture partners. Capacity 6,000 m2 In focus: Advanced Recontouring Process (ARP) The Advanced Recontouring Process (ARP) is unique worldwide. Worn compressor blades are first electronically analyzed and then re-contoured in a precision method using robot technology. The restored profile of the engine compressor blades is calculated as a factor of the reduced chord-length of the worn blades so that the best possible aerodynamic profile is obtained.
    [Show full text]
  • SSA Phase II Final Report.Book
    Solid State Aircraft Phase II Project NAS5-03110 Final Report Prepared for: Robert A. Cassanova, Director NASA Institute for Advanced Concepts May 31, 2005 Table of Contents Table of Contents List of Tables .............................................................................................................. iii List of Figures ............................................................................................................. v List of Contributors .................................................................................................. xv Executive Summary ................................................................................................ xvii Chapter 1.0 Introduction ............................................................................................ 1 1.1 SSA Concept Description ..........................................................................................................1 1.2 Flapping Wing Flight ..................................................................................................................4 1.2.1 Insect Flight .........................................................................................................................5 1.2.2 Bird, Mammal and Dinosaur Flight ......................................................................................8 1.2.3 Wing Shape .......................................................................................................................12 1.3 Mission Capabilities .................................................................................................................15
    [Show full text]
  • Airfoil Self-Noise and Prediction
    NASA Reference Publication 1218 July 1989 Airfoil Self-Noise and Prediction Thomas F. Brooks, D. Stuart Pope, and Michael A. Marcolini Uncla s I-/1/71 01£77 17 I NASA Reference Publication 1218 1989 Airfoil Self-Noise and Prediction Thomas F. Brooks Langley Research Center Hampton, Virginia D. Stuart Pope PRC Kentron, Inc. Aerospace Technologies Division Hampton, Virginia Michael A. Marcolini Langley Research Center Hampton, Virginia National Aeronautics and Space Administration Office of Management Scientific and Technical Information Division Contents Suminary .................................. 1 1. Introduction ................................ 2 1.1. Noise Sources and Background ...................... 2 1.1.1. Turbulent-Boundary-Layer Trailing-Edge (TBL-TE) Noise ........ 2 1.1.2. Separation-Stall Noise ........................ 3 1.1.3. Laminar-Boundary-Layer-Vortex-Shedding (LBL VS) Noise ....... 3 1.1.4. Tip Vortex Formation Noise ..................... 4 1.1.5. Trailing-Edge-Bluntness Vortex-Shedding Noise ............. 4 1.2. Overview of Report ........................... 4 2. Description of Experiments ......................... 5 2.1. Models and Facility ........................... 5 2.2. Instrumentation ............................ 5 2.3. Test Conditions ............................. 5 2.4. Wind Tunnel Corrections ........................ 5 3. Boundary-Layer Parameters at the Trailing Edge ................ 9 3.1. Scaled Data .............................. 9 3.2. Calculation Procedures ......................... 9 . Acoustic Measurements
    [Show full text]
  • Compressor Airfoil Protective Coatings for Turbine Engine Fuel Efficiency (WP-201009) Objective
    Compressor Airfoil Protective Coatings for Turbine Engine Fuel Efficiency (WP-201009) Objective The objective of this project is to demonstrate potential fuel savings on fixed wing (transport and fighter aircraft) and ground vehicle weapon system platforms operating with an erosion-corrosion (E/C) resistant coating on compressor airfoils via model analysis, simulation/laboratory testing, and field service evaluation. Technology Description The E/C resistant coating is a multilayer ceramic-metallic matrix that is applied in a vacuum via a cathodic arc, physical vapor deposition (CAPVD) process. Design elements in the coating allow it to survive in the austere environments of a gas turbine engine and withstand specific failure mechanisms. The E/C resistant coating applied to stainless steel compressor airfoils is the first coating known in the industry to successfully pass corrosion tests on a repeatable basis while effectively providing erosion protection. The coatings for the transport aircraft will undergo field service evaluations comparing the performance of coated engines to uncoated engines. The coating for tank engines will undergo a back-to-back engine sand ingestion test. Laboratory erosion testing followed by computer performance modeling comparisons of coated and uncoated engines will be conducted on the fixed-wing engine applications. The fighter, fixed-wing engine will rely solely on modeling and analyses based on field data to determine potential fuel savings for aircraft such as the F/A-18. Benefits This project will demonstrate E/C resistant coatings applied to gas turbine engine compressor airfoils that can decrease fuel consumption, lower carbon emissions, and decrease maintenance support requirements across fixed-wing and land-based weapon system platforms.
    [Show full text]
  • Robot Dynamics Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling
    Robot Dynamics Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling 151-0851-00 V Marco Hutter, Roland Siegwart, and Thomas Stastny Autonomous Systems Lab Autonomous Systems Lab Robot Dynamics - Fixed Wing UAS: Basics of Aerodynamics | 20.12.2016 | 1 Contents | Fixed Wing UAS 1. Introduction/(brief) Historical Overivew 2. Basics of Aerodynamic 3. Aircraft Dynamic Modeling 4. Aircraft Performance (wrap-up) 5. Aircraft Stability 6. Simulation 7. Modeling for Control 8. Fixed-wing Control Autonomous Systems Lab Robot Dynamics – Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling | 20.12.2016 | 2 Historical Overview Autonomous Systems Lab Robot Dynamics – Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling | 20.12.2016 | 3 http://en.wikipedia.org/wiki/Montgolfier Historical Overview . First Flight: Montgolfier Brothers 1783 . Ballon filled with hot air . First unmanned demonstrations . Later with animals . Finally manned Autonomous Systems Lab Robot Dynamics – Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling | 20.12.2016 | 4 Historical Overview . Otto Lilienthal . First person to make repeated successful short flights . Used a fixed wing glider . Died after a crash in 1896, saying “Sacrifices must be made” http://en.wikipedia.org/wiki/Otto_Lilienthal Autonomous Systems Lab Robot Dynamics – Fixed Wing UAS: Basics of Aerodynamics & Dynamic Modeling | 20.12.2016 | 5 Historical overview . Wright brothers . Started as glider engineers and pilots . First engine powered flight in 1903 . First to actively manipulate the plane
    [Show full text]
  • External Burning in Supersonic Streams
    Combustion in the air stream adjacent to a body flying at supersonic speeds produces forces on the body, because the heated air layer acts as a volume source to deflect neighboring air layers. Net thrust can be produced by external burning near rearward facing surfaces of appropriately shaped bodies or wings. Both experimental and analytical results show that "external burning ramjets" could be used for hypersonic cruise (or simply for drag reduction) but are unattractive for primary propulsion systems that must provide a significant acceleration capability. However, substantial forces normal to a body can be produced efficiently, so that a promising application of external burning is for steering control systems. Fuel specific impulses may be F. S. Billig and G. L. Dugger four to ten times those achievable with simple jet reaction systems. EXTERNAL BURNING IN SUPERSONIC STREAMS wenty years ago, when ramjets were just fuels could indeed be burned in the supersonic flow T beginning to become useful devices and the fields around various body shapes. Meanwhile, at theory of subsonic heat release in their burners was the Forest Grove " Burner Lab " of APL, the still being developed, a few adventurous spirits writers had undertaken to prove that an "external were already looking ahead to the possibility of ramjet," i.e., burning beneath a flat-topped, tri­ burning in supersonic streams. 1, 2 By 1951 experi­ angular airfoil, could produce net thrust as well as ments on drag reduction of supersonic projectiles lift at Mach 5 (approximately 3500 mph). The first by burning in the projectile's wake had been con­ burning test in 1959 was successful in this regard.
    [Show full text]