Airfoil Design
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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. -
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. -
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. -
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. -
The Aerodynamic Design of Wings with Cambered Span Having Minimum Induced Drag
https://ntrs.nasa.gov/search.jsp?R=19640006060 2020-03-24T06:40:56+00:00Z View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NASA Technical Reports Server TR R-152 NASA- ..ZC_ L mm-4 -0-= I NATIONAL AERONAUTICS AND -----I- SPACE ADMINISTRATION LC)A~\c;i)p E AFW Wm* EP1 KIRTLANi =$= MS; TECHNICAL REPORT R-152 THE AERODYNAMIC DESIGN OF WINGS WITH CAMBERED SPAN HAVING MINIMUM INDUCED DRAG BY CLARENCE D. CONE, JR. 1963 ~ For -le by the Superintendent of Documents. US. Government Printing OIBce. Wasbingbn. D.C. 20402. Single copy price, 35 cents TECH LIBRARY KAFB, NM 00b8223 TECHNICAL REPORT R-152 THE AERODYNAMIC DESIGN OF WINGS WITH CAMBERED SPAN HAVING MINIMUM INDUCED DRAG By CLARENCE D. CONE, JR. Langley Research Center Langley Station, Hampton, Va. I CONTENTS Page SU~MMARY-________._...-.--..--.---------------------------------------- 1 INTRODUCTION __.._.._..__..___..~___.__._.._....~....~~-_--~~--~-------1 SYMBOLS___._____.___------.----------.---.--.---.---------------.--.--- 2 THE ])RAG POLAR OF CAMBERED-SPAN WINGS-_- - ...______________.__ 3 PROPERTIES OF CAMBERED WINGS HAVING MINIMUM INDUCED DRAG_._.._.___.~._.___~_._.___.._.____..__.__.-~~_-~---_---~~---------4 The Optimum Circulation IXstribution.. - -.- - -.- - - - - - - - - - - - - - - -.- - - - - - -.- - 4 The Effective Aspect Ratio ______________._._._____________________------5 THE DESIGN OF CAMBERED WINGS ____________________________________ 6 I>et,erininationof the Wing Shape for Maximum LID- - -.--_-___-___-___--__ 7 Specification of design requirements- - - - - - - - - - - - - - - -.-. - - - - - - - - - - - - - - - - 8 1)eterniination of minimum value of chord function- - - -.- - - - - - - - - - - - - - 8 Determination of wing profile-drag coefficient and optimum chord function- - 9 The optimum cruise altitude- -. -
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. -
10. Supersonic Aerodynamics
Grumman Tribody Concept featured on the 1978 company calendar. The basis for this idea will be explained below. 10. Supersonic Aerodynamics 10.1 Introduction There have actually only been a few truly supersonic airplanes. This means airplanes that can cruise supersonically. Before the F-22, classic “supersonic” fighters used brute force (afterburners) and had extremely limited duration. As an example, consider the two defined supersonic missions for the F-14A: F-14A Supersonic Missions CAP (Combat Air Patrol) • 150 miles subsonic cruise to station • Loiter • Accel, M = 0.7 to 1.35, then dash 25 nm - 4 1/2 minutes and 50 nm total • Then, must head home, or to a tanker! DLI (Deck Launch Intercept) • Energy climb to 35K ft, M = 1.5 (4 minutes) • 6 minutes at M = 1.5 (out 125-130 nm) • 2 minutes Combat (slows down fast) After 12 minutes, must head home or to a tanker. In this chapter we will explain the key supersonic aerodynamics issues facing the configuration aerodynamicist. We will start by reviewing the most significant airplanes that had substantial sustained supersonic capability. We will then examine the key physical underpinnings of supersonic gas dynamics and their implications for configuration design. Examples are presented showing applications of modern CFD and the application of MDO. We will see that developing a practical supersonic airplane is extremely demanding and requires careful integration of the various contributing technologies. Finally we discuss contemporary efforts to develop new supersonic airplanes. 10.2 Supersonic “Cruise” Airplanes The supersonic capability described above is typical of most of the so-called supersonic fighters, and obviously the supersonic performance is limited. -
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. -
N AL ADVISORY COMMITTEE for AERONAUTICS WASHINGTON July 12, 1957 NACA RM L57e24a
SOME FACTORS AFFECTING THE'STATIC LONGITU DIRECTIONAL STABILITY CHARACTEXISTICS OF SUPERSONIC AIRCRAFT CONFIGURATIONS By M. Leroy Spearman Langley Aeronautical Laboratory Langley Field, Va. N AL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON July 12, 1957 NACA RM L57E24a NATI SOME FACTORS AFFECTING TflE STATIC LONGITUDINAL AND DIRECTIONAL STABILITY CHARACTERISTICS OF SUPERSONIC AIRCRAFT CONFIGURATIO~S By M. kroy Spearman SUMMARY A survey is made of the problems introducei by Le ,,icreased -0ngi- tudinal stability and the reduced directional stability of aircraft operating in the low supersonic speed range. The longitudinal stability increases markedly at supersonic speeds and results in high drags due to trimming and in limited control for maneuvering. The large untrimmed pitching moments can be reduced and the control requirements alleviated to some extent through the use of fuselage camber. The use of canard configurations offers some promise of reducing the drag due to trimming and increasing the controllhbility. The directional stability generally deteriorates rapidly at super- sonic speeds because of the reduction in vertical-tail lift-curve slope coupled with the large unstable yawing moment of the fuselage. The vertical-tail contribution is shown to be affected by many factors including the wing position, the fuselage shape, and the horizontal-tail position. The directional stability can be increased, particularly at high angles of attack, by such devices as ventral fins and forebody strakes. In addition, indications are that the directional stability might be improved through modifications to the fuselage afterbody. INTRODUCTION Aircraft advancing from subsonic to low supersonic speeds frequently encounter performance and control problems as a result of significant changes in static stability characteristics. -
Further Devels'nent Ofthe Tunny
FURTHERDEVELS'NENT OF THETUNNY RIG E M H GIFFORDANO C PALNER Gi f ford and P art ners Carlton House Rlngwood Road Hoodl ands SouthamPton S04 2HT UK 360 1, lNTRODUCTION The idea of using a wing sail is not new, indeed the ancient junk rig is essentially a flat plate wing sail. The two essential characteristics are that the sail is stiffened so that ft does not flap in the wind and attached to the mast in an aerodynamically balanced way. These two features give several important advantages over so called 'soft sails' and have resulted in the junk rig being very successful on traditional craft. and modern short handed-cruising yachts. Unfortunately the standard junk rig is not every efficient in an aer odynamic sense, due to the presence of the mast beside the sai 1 and the flat shapewhich results from the numerousstiffening battens. The first of these problems can be overcomeby usi ng a double ski nned sail; effectively two junk sails, one on either side of the mast. This shields the mast from the airflow and improves efficiency, but it still leaves the problem of a flat sail. To obtain the maximumdrive from a sail it must be curved or cambered!, an effect which can produce over 5 more force than from a flat shape. Whilst the per'formanceadvantages of a cambered shape are obvious, the practical way of achieving it are far more elusive. One line of approach is to build the sail from ri gid componentswith articulated joints that allow the camberto be varied Ref 1!. -
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. -
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