Summary of Low-Speed Airfoil Data - University of Illinois ...

1 Summary of Low-Speed Airfoil data MichaelS. Selig, James J. Guglielmo, Andy P. Broeren and Philippe Giguere Volume 1 Summary of Low-Speed Airfoil data Volume 1 About the Authors DR. MICHAEL S. SELIG, an accomplished applied aerodynamicist and Airfoil designer, is an Assistant Professor of Aeronautical and Astronautical Engineering at the University of Illinois at Urbana-Champaign. He received his (1984) from the University of Illinois , his (1988) from Princeton University and his (1992) from the Pennsylvania State University . His current research areas include low Reynolds number Airfoil aerodynamics, multi-point inverse design of slot suction airfoils , horizontal-axis wind-turbine system design and analysis, and flight simulation. He teaches courses in applied aerodynamics and aircraft design. JAMES J. GUGLIELMO received his Bachelor of Science degree in Aeronautical and Astro-nautical Engineering from the University of Illinois at Urbana-Champaign in May 1992.

2 Remaining at the University of Illinois for graduate studies, his research has included such topics as experimental supersonic and subsonic wind-tunnel testing, Magnetic Levitation (MagLev) vehicle design, and the conceptual design of a wing-in-ground-effect aircraft. Mr. Guglielmo is also the co-founder and present coordinator of the UIUC Low-Speed Air-foil Tests and is working toward a Master of Science degree in experimental low Reynolds number Airfoil aerodynamics. Research interests include applied aerodynamics, flight me-chanics, and aircraft conceptual/ advanced design. ANDY P. BROEREN received his Bachelor of Science degree in Mechanical Engineering from the Milwaukee School of Engineering, Milwaukee, Wisconsin in 1993. Several months after beginning graduate study in mechanical engineering at the University of Illinois , he joined Prof. Selig and Mr. Guglielmo in their efforts to establish a program for testing low Reynolds number airfoils . In addition to continuing work in this area, Mr.

3 Broeren is presently working toward a Master of Science degree with thesis research in unsteady fluid mechanics. His interest in aerodynamics, particularly involving high-lift, low Reynolds number Airfoil research, results from several years of participation in the Society of Automotive Engineer's ( ) Aero-Design competition. PHILIPPE GIGUERE received his Bachelor of Mechanical Engineering degree from McGill University , Montreal, Canada in 1992 and his Master of Science degree from Universite Laval, Quebec, Canada in 1994. Shortly after receiving his Master's degree, he joined the Department of Aeronautical and Astronautical Engineering at the University of Illi-nois at Urbana-Champaign. He is currently working toward a degree with research in optimization of wind turbine rotors, wind-tunnel boundary-layer corrections and Airfoil performance enhancement. His experience with R/C model airplanes comes from his par-ticipation in the Society of Automotive Engineer's ( ) Aero-Design competition from 1991-1994.

4 He also flies full-scale gliders. Michael S. Selig James J. Guglielmo Andy P. Broeren Philippe Giguere Department of Aeronautical and Astronautical Engineering University of Illinois at Urbana-Champaign Summary of Low-Speed Airfoil data Volume 1 SoarTech Publications Virginia Beach, Virginia SOARTECH PUBLICATIONS 1504 N. Horseshoe Circle Virginia Beach, Virginia 23451, USA Copyright 1995 by MichaelS. Selig, James J. Guglielmo, Andy P. Broeren, and Philippe Giguere All rights reserved. Cover photograph by Bill Weigand, University of Illinois News Bureau Wind tunnel model (81223} by Yvan Tinel, Tinel Technologies, Northbrook, Illinois First Printing, June 1995 Library of Congress Cataloging in Publication data Selig, Michael Scott Summary of Low-Speed Airfoil data , Volume 1 / by Michael Selig, James Guglielmo, Andy Broeren and Philippe Giguere. Includes bibliographical references. 1. Aerofoils. 2. Aerodynamics. 3. Airplanes-Models. I. model Aviation. II. Title 95-69524 ISBN 0-9646747-1-8 Contents PREFACE ACKNOWLEDGMENTS Airfoil data DISTRIBUTION LIST OF FIGURES LIST OF TABLES LIST OF SYMBOLS 1 THE airfoils TESTED 2 3 WIND-TUNNEL FACILITY AND MEASUREMENT TECHNIQUES EXPERIMENTAL FACILITY MEASUREMENT TECHNIQUES LIFT FORCE MEASUREMENTS DRAG FORCE MEASUREMENTS Airfoil model ACCURACY MEASUREMENTS FREESTREAM VELOCITY MEASUREMENTS data REDUCTION WIND-TUNNEL BOUNDARY CORRECTIONS ADDITIONAL VELOCITY CORRECTIONS CORRECTIONS TO MEASURED QUANTITIES CALIBRATIONS AND UNCERTAINTY ANALYSIS COMPARISON WITH OTHER FACILITIES Summary OF Airfoil data airfoils FOR FREE FLIGHT MODELS airfoils FOR THERMAL DURATION SAILPLANES airfoils FOR F3B SAILPLANES airfoils FOR SLOPE RACERS airfoils FOR TAIL SECTIONS airfoils FOR QUICKIE 500 PYLON RACERS airfoils FOR SPORT PLANES airfoils FOR HEAVY-LIFT CARGO PLANES airfoils FOR SMALL WIND TURBINES 4 Airfoil PROFILES AND PERFORMANCE PLOTS iii.)

5 V . ix .xi xvii = 1 3 3 7 8 9 13 13 14 14 16 16 18 18 23 27 31 34 39 40 42 43 45 51 53 ii Summary of Low-Speed Airfoil data EXTENDED NOTES TO THE TEXT REFERENCES APPENDIX A Airfoil COORDINATES APPENDIX B Airfoil POLAR data . APPENDIX C UIUC Low-Speed Airfoil TESTS MANIFESTO 245 249 253 277 289 Preface A reader just discovering Airfoil aerodynamics will find it helpful to reference the companion book airfoils at Low Speeds (by Selig, Donovan and Fraser), which was first published as SoarTech 8 in 1989. The book presents the results of wind-tunnel tests conducted at Princeton University on over 60 airfoils for model aircraft (mostly radio controlled sailplanes), and it also introduces the terminology and jargon used here in discussing airfoils at low speeds, specifically, airfoils at low Reynolds numbers. When the wind-tunnel tests were completed at Princeton in January 1989, no continuation of that effort was planned. In the hope that the tests could be later continued, however, the experimental apparatus and the assorted wind-tunnel models were put in safe storage.

6 Michael Selig continued his graduate studies at Penn State ( in Aerospace Engineering) and John Donovan ( from Princeton) accepted a position at McDonnell Douglas in St. Louis. Sadly, David Fraser died in an aircraft icing accident in January 1992. As this book reveals, the opportunity to continue the Low-Speed Airfoil test effort has emerged. In August 1992, Selig joined the faculty in the Department of Aeronautical and Astronautical Engineering at the University of Illinois at Urbana-Champaign. In brief chronological order, re-establishing the Airfoil test capability was initiated with the help of two graduate students-Jim Guglielmo ( ) and Tony Balow ( ). Support from modelers was solicited in Decem-ber 1993, and the test program was named the UIUC Low-Speed Airfoil Tests. (The tremendous generosity of all those who have contributed to the project is discussed in the acknowledgments.) Preliminary tests were performed in April 1994. Andy Broeren ( ) volunteered to join the test team in May 1994.

7 Philippe Giguere ( ) volunteered to start work on the project in August 1994. The extensive data collection effort mounted for this book took place over a one month period from mid-December 1994 to mid-January 1995. More re-cently, Cameron Ninham ( ) and Ashok Gopalarathnam ( ) have offered to play a role in future testing. To date, only Jim Guglielmo has been supported (since July 1994) on funds donated by modelers. This Book and Its Organization Summary of Low-Speed Airfoil data is only the first in what should be a series of volumes that document the ongoing low Reynolds number Airfoil tests at the University of Illinois at Urbana-Champaign. In this volume, the airfoils tested cover a broad spectrum that includes airfoils for free flight model aircraft, heavy lift R/C aircraft and, of course, R/C sailplanes, to name just a few. As an overview, the 34 airfoils tested are briefly introduced in Chapter 1. iv Summary of Low-Speed Airfoil data Chapter 2 is to a discussion of the wind-tunnel test facility and the experimental procedures.

8 This chapter can be skipped by those less interested in the myriad of issues that arise in wind-tunnel testing. Of course, the importance of the methods used in taking and reducing the data cannot be over-emphasized. Although the data collection effort was performed in little more than a month, nearly two and a half years were spent in preparation for the tests. Fortunately, future tests will not require as much preparation time. This book is primarily designed to be used as a reference for low Reynolds number Airfoil data . In Chapter 3, a discussion of all the airfoils is given first; then the figures ( Airfoil plots and performance data ) are presented in Chapter 4. The discussion is organized according to the application ( , free flight model airfoils are first discussed, then F3B airfoils and so on for each category). The figures in Chapter 4, however, are organized alphabetically by the Airfoil name. For quick referencing of the figures in Chapter 4, the Airfoil name is listed in the margin below the page number.

9 Finally, the tabulated Airfoil coordinates and performance data (available on diskette) are given in Appendices A and B. Appendix C contains the UIUC Low-Speed Airfoil Tests Manifesto that outlines the scope and purpose of this work. Acknowledgments The Airfoil testing effort would not have been possible without the support of a large number of people. To each of them we are indebted. In particular, for monetary contributions that were used for equipment and a graduate student research assistantship, we are especially grateful to the following organizations, clubs, businesses, individuals and t-shirt patrons. Shown in parentheses for each category is that category's fraction of the total support received. Note that some people are listed more than once since they have helped in different capacities. Organizations (10%): academy of model aeronautics (with special ap-preciation to Bob Underwood and others), !SF-International R/C Soaring Forum (with special appreciation to Rolf Girsberger), National Association of Rocketry (Mark Bundick), and National Free Flight Society (with special appreciation to Bob Waterman).

10 Businesses (17%): Airtronics, Inc. (Bob and Tim Renaud), B2 Stream-lines (Bill & Bunny Kuhlman), Dan Parsons Products (Dan Parson), F3F Newsletter (Preben Norholm), Gulf R/C (John Rimmer), Kennedy Compos-ites (Barry Kennedy), Landing Products (Fred Burgdorf), Northeast Sailplane Products (Carolyn & Sal DeFranceso), Planeador RC News-Spain (Peter Atkinson, editor) R/C Soaring Digest (Jerry & Judy Slates), Slegers Interna-tional, Inc. (Ed Slegers), SoarTech Publications ( Stokely) and Websoft, Inc. (Robert Webster). model Clubs (8%): , Champaign County Radio Control Club, Clent Soaring Association, Downest Soaring Club, Fairlop Silent Flyers (Eng-land), Florida Soaring Society, FMSG Alling/Obb. (Germany), Greek Aero-modelling Federation (Greece), Ivinghoe Soaring Assoc., Lincoln Area Soar-ing Society, Miniature Aircraft Association of Westchester County (England), North American Scale Soaring Association, Northeast Drone Society, Padu-cah Aero Modelers, Pasadena Soaring Society, Pennisula Channel Comman-ders, Portland Area Sailplane Society, Round Valley Radio Control Club, , , , San Gabriel Valley Radio Control League, Santa Clarita Soaring Assoc.