OutlineHistoryCompressible FlowTransonic Drag RiseComputational Fluid DynamicsEpilogueAeronautical HistoryImportant Advances in Aircraft DesignDavid A. CaugheySibley School of Mechanical & Aerospace EngineeringCornell UniversityIthaca, New York 14853-7501M&AE 3050Introduction to AeronauticsAugust 28, 02008Outline•Background of D. A. Caughey•B. S. in in Aeronautics & Astronautics; University of Michigan•Ph. D. in Aerospace & Mechanical Sciences; Princeton University•Research Post-doctoral year in Moscow, U.S.S.R.•3 1/2 years in aerodynamic research at McDonnell Douglas Corp. (St. Louis)•30 plus years research in computational aerodynamics and fluid mechanics•30 plus years teaching fluid mechanics, aerodynamics, and flight dynamics•Overview of Aeronautics•History of heavier-than-air flight•Important trends in aircraft design•Compressibility Effects•Computational fluid dynamicsHistorySir George Cayley (1773 – 1857)•First successful gliders•Understood importance of separating lift and propulsion•Understood importance of dihedral•Developed whirling-arm apparatus to measure forces on airfoils and wings•Understood importance of camberFigure: The Cayley medallion; struck in silver by Cayley in 1799HistoryOtto Lilienthal (1848 – 1896)•“Father" of hang-gliding•Understood importance of control•Developed extensive tables of lift and drag forces based on (flawed)whirling-arm experiments•Died as a result of injuries sustained in a glider crashFigure: Two versions of Lilienthal glidersHistoryOctave Chanute 1832 – 1910•French-born American railroad engineer andaviation pioneer•Brought European aeronautical knowledge toU.S.•Published Progress in Flying Machines in1894•Was helpful to, and supportive of, the Wrightbrothers“Let us hope that the advent of a successful flying machine ... will bring nothing but goodinto the world; that it shall abridge distance, make all parts of the globe accessible, ... andhasten the promised era in which there shall be nothing but peace and goodwill among allmen."from Progress in Flying MachinesHistoryWilbur (1867 – 1912) & Orville (1871 – 1948) Wright•Understood importance of 3-axis control (but not stability) – learned to controlflight in extensive glider experiments•Discovered errors in Lilienthal’s whirling-arm data•Built wind-tunnel for aerodynamic testing•Developed first theory for propellers (and built one that had better than 80%efficiency)Figure: First heavier-than-air sustained flight; 1903History(a) 1903 Wright Flyer(b) Bleriot XI; replica of first aircraft to crossthe English Channel in 1909(c) 1927 Ryan Monoplane(d) Two objects having the same drag in turbulent flowHistory(a) 1903 Wright Flyer(b) Bleriot XI; replica of first aircraft to crossthe English Channel in 1909(c) 1927 Ryan Monoplane(d) Two objects having the same drag in turbulent flowHistory(a) 1927 Ryan Monoplane(b) Boeing 247; first flight February 1933(c) Douglas DC-3; first flight December 1935Boeing 247 and Douglas DC-3 had:•Retractable landing gear•Fully cantilevered wing•Monocoque construction•Wing flaps•Low-drag engine cowlingThe Boeing 247 was the first commercial aircraft to incorporate these features, but the DC-3was more successful because of its ability to carry twice as many passengers as the 247.History(a) Boeing Stratoliner; December 1938(b) Douglas DC-6; February 1946Engine superchargers, combined with cabin pres-surization, allowed flight at altitudes above mostweather disturbances, greatly increasing passengercomfort. (Note: The associated development of ra-dial flow compressors provided important technol-ogy for the development of early jet engines.)History(a) Boeing Stratocruiser; July 1947(b) Douglas DC-7; May 1953(c) Lockheed Constellation; January 1943End-of-an-era piston-powered transportaircraft: the ultimate in piston-power.Some models began to incorporate com-pound engines, the development ofwhich helped to usher in the age of jetpowered aircraft.History(a) Messerschmitt Me 262; July 1942(b) Gloster Meteor; March 1943(c) Lockheed P-80; January 1944Dawn of the jet age:•Jet fighter (or fighter-bomber)aircraft•Moderately swept (if at all) wingsHistory(a) Boeing 707; December 1957(b) Douglas DC-8; May 1958(c) DeHavilland Comet; July 1949•First commercial jet aircraft•Four, wing-mounted engines (internallyor in nacelles)•Swept wingsLater Jet PowerHistory 0 100 200 300 400 500 600 700 800 1920 1940 1960 1980 2000 2020Cruise speed, mphYear of First FlightHistory of Airliner Speeds•First half century•Reasonableextrapolation(?)•Second half century•Speed of soundHistory 0 100 200 300 400 500 600 700 800 1920 1940 1960 1980 2000 2020Cruise speed, mphYear of First FlightHistory of Airliner Speeds•First half century•Reasonableextrapolation(?)•Second half century•Speed of soundHistory 0 100 200 300 400 500 600 700 800 1920 1940 1960 1980 2000 2020Cruise speed, mphYear of First FlightHistory of Airliner Speeds•First half century•Reasonableextrapolation(?)•Second half century•Speed of soundHistory 0 100 200 300 400 500 600 700 800 1920 1940 1960 1980 2000 2020Cruise speed, mphYear of First FlightHistory of Airliner Speeds•First half century•Reasonableextrapolation(?)•Second half century•Speed of soundHistory(a) McDonnell Douglas DC-10; August 1970(b) Boeing 777; June 1994(c) Airbus A380; April 2005(d) Boeing 787; December 2008(?)Early Jet PowerCompressible FlowMach = 0.0Signal propagation in a compressible fluidCompressible FlowMach = 0.5Signal propagation in a compressible fluidCompressible FlowMach = 1.0Signal propagation in a compressible fluidCompressible FlowMach = 2.0Signal propagation in a compressible fluidCompressible FlowM∞= 0.20 M∞= 0.40 M∞= 0.50M∞= 0.60 M∞= 0.70 M∞= 0.75Figure: Contours of constant Mach number for inviscid flow past RAE 2822 airfoil at α = 3.0◦angle of attack. Contour spacing is ∆M = 0.05. Solutions to the Euler equations of inviscidflow are computed numerically on 320 × 64 cell grids using Jameson-Caughey LU-SGS scheme.Compressible Flow-2-1.5-1-0.5 0 0.5 1 1.5 0 0.2 0.4 0.6 0.8 1Pressure CoefficientChordwise position, x/cSurface Pressure, Total Enthalpy, and Entropy Change DistributionsPressure coefficient Total enthalpy (x100)Total pressure (x10)-2-1.5-1-0.5 0 0.5 1 1.5 0 0.2 0.4 0.6 0.8 1Pressure CoefficientChordwise position, x/cSurface Pressure, Total Enthalpy, and Entropy