Aircraft Drag Polar Estimation Based on a Stochastic Hierarchical Model
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Subsonic Aircraft Wing Conceptual Design Synthesis and Analysis
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by GSSRR.ORG: International Journals: Publishing Research Papers in all Fields International Journal of Sciences: Basic and Applied Research (IJSBAR) ISSN 2307-4531 (Print & Online) http://gssrr.org/index.php?journal=JournalOfBasicAndApplied --------------------------------------------------------------------------------------------------------------------------- Subsonic Aircraft Wing Conceptual Design Synthesis and Analysis Abderrahmane BADIS Electrical and Electronic Communication Engineer from UMBB (Ex.INELEC) Independent Electronics, Aeronautics, Propulsion, Well Logging and Software Design Research Engineer Takerboust, Aghbalou, Bouira 10007, Algeria [email protected] Abstract This paper exposes a simplified preliminary conceptual integrated method to design an aircraft wing in subsonic speeds up to Mach 0.85. The proposed approach is integrated, as it allows an early estimation of main aircraft aerodynamic features, namely the maximum lift-to-drag ratio and the total parasitic drag. First, the influence of the Lift and Load scatterings on the overall performance characteristics of the wing are discussed. It is established that the optimization is achieved by designing a wing geometry that yields elliptical lift and load distributions. Second, the reference trapezoidal wing is considered the base line geometry used to outline the wing shape layout. As such, the main geometrical parameters and governing relations for a trapezoidal wing are -
Redesign of the Gossamer Albatross Using a Boxwing Armando R
Redesign of the Gossamer Albatross using a Boxwing Armando R. Collazo Garcia III, Undergraduate Student-Aerospace Engineering, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, [email protected] April 12, 2017 ABSTRACT Historically, human powered aircraft (HPA) have been known to have very large wingspans; the main reason being for aerodynamic performance. During low speeds, the predominant type of drag is the induced drag which is a by-product of large wing tip vortices generated at higher lift coefficients. In order to reduce this phenomenon, higher aspect ratio wings are used which is the reason behind the very large wingspans for HPA. Due to its high Oswald efficiency factor, the boxwing configuration is presented as a possible solution to decrease the wingspan while not affecting the aerodynamic performance of the airplane. The new configuration is analyzed through the use of VLAERO+©. The parasitic drag was estimated using empirical methods based on the friction drag of a flat plate. The structural weight changes in the boxwing design were estimated using “area weights” derived from the original Gossamer Albatross. The two aircraft were compared at a cruise velocity of 22 ft./s where the boxwing configuration showed a net drag reduction of approximately 0.36 lb., which can be deduced from a decrease of 0.81 lb. of the induced drag plus an increase of the parasite drag of around 0.45 lb. Therefore, for an aircraft with approximately half the wingspan, easier to handle, and more practical, the drag is essentially reduced by 4.4%. INTRODUCTION METHODOLOGY RESULTS Because of the availability of information and data, the Gossamer A boxwing of roughly half the span of the Albatross with the same airfoil, root chord, fuselage and taper ratio was modeled in VLAERO+©. -
Introduction to Aerospace Engineering
Introduction to Aerospace Engineering Lecture slides Challenge the future 1 15-12-2012 Introduction to Aerospace Engineering 5 & 6: How aircraft fly J. Sinke Delft University of Technology Challenge the future 5 & 6. How aircraft fly Anderson 1, 2.1-2.6, 4.11- 4.11.1, 5.1-5.5, 5.17, 5.19 george caley; wilbur wright; orville wright; samuel langley, anthony fokker; albert plesman How aircraft fly 2 19th Century - unpowered Otto Lilienthal (1848 – 1896) Was fascinated with the flight of birds (Storks) Studied at Technical School in Potsdam Started experiment in 1867 Made more than 2000 flights Build more than a dozen gliders Build his own “hill” in Berlin Largest distance 250 meters Died after a crash in 1896. No filmed evidence: film invented in 1895 (Lumiere) How aircraft fly 3 Otto Lilienthal Few designs How aircraft fly 4 Hang gliders Derivatives of Lilienthal’s gliders Glide ratio E.g., a ratio of 12:1 means 12 m forward : 1 m of altitude. Typical performances (2006) Gliders (see picture): V= ~30 to >145 km/h Glide ratio = ~17:1 (Vopt = 45-60 km/h) Rigid wings: V = ~ 35 to > 130 km/h Glide ratio = ~20:1 (Vopt = 50-60 km/h) How aircraft fly 5 Question With Gliders you have to run to generate enough lift – often down hill to make it easier. Is the wind direction of any influence? How aircraft fly 6 Answer What matters is the Airspeed – Not the ground speed. The higher the Airspeed – the higher the lift. So if I run 15 km/h with head wind of 10 km/h, than I create a higher lift (airspeed of 25 km/h) than when I run at the same speed with a tail wind of 10 km/h (airspeed 5 km/h)!! That’s why aircraft: - Take of with head winds – than they need a shorter runway - Land with head winds – than the stopping distance is shorter too How aircraft fly 7 Beginning of 20th century: many pioneers Early Flight 1m12s Failed Pioneers of Flight 2m53s How aircraft fly 8 1903 – first powered HtA flight The Wright Brothers December 17, 1903 How aircraft fly 9 Wright Flyer take-off & demo flight Wright Brothers lift-off 0m33s How aircraft fly 10 Wright Brs. -
Cessna 172 Maneuvers Guide Private Single-Engine, Commercial Single-Engine, and CFI Single-Engine
Cessna 172 Maneuvers Guide Private Single-Engine, Commercial Single-Engine, and CFI Single-Engine GROUND USE ONLY Steep Turns Power-Off Stall 1. Perform two 90º clearing turns See Policies and Procedures — Stalls 2. 90 KIAS (*2000 RPM) maintain altitude 1. Perform two 90° clearing turns 3. Cruise configuration flow 2. *1500 RPM (maintain altitude) 4. Roll into 45˚ bank (private, at least 50˚ for commercial) 3. Landing configuration flow 5. Maintain altitude and airspeed 4. Stabilized descent at 65 KIAS (+ back pressure, + approx. 1-200 RPM) 5. Throttle idle (Slowly) 6. Roll out ½ bank angle prior to entry heading 6. Wings level or up to 20° bank as assigned 7. Clear traffic and roll in opposite direction 7. Pitch to maintain altitude (Slowly) 8. Roll out ½ bank angle prior to entry heading 8. At stall/buffet (as required) recover – reduce AOA - full power 9. Cruise checklist 9. Reduce flaps to 10° 10. Accelerate to 60 KIAS (VX), positive rate, reduce flaps to 0° 11. Cruise checklist Slow Flight Power-On Stall 1. Perform two 90º clearing turns See Policies and Procedures — Stalls 2. *1500 RPM (maintain altitude) 1. Perform two 90° clearing turns 3. Landing configuration flow 2. *1500 RPM (maintain altitude) 4. Maintain altitude - slow to just above a stall 3. Clean configuration 5. Power as required to maintain airspeed 4. At 60 KIAS, simultaneously increase pitch (Slowly) and apply full power 6. Accomplish level flight, climbs, turns, and descents as required 5. Slowly increase pitch to induce stall/buffet (approx 15°) (ATP - max 30° bank) 6. At stall/buffet (as required) recover – reduce AOA - full power 7. -
FAA-H-8083-3A, Airplane Flying Handbook -- 3 of 7 Files
Ch 04.qxd 5/7/04 6:46 AM Page 4-1 NTRODUCTION Maneuvering during slow flight should be performed I using both instrument indications and outside visual The maintenance of lift and control of an airplane in reference. Slow flight should be practiced from straight flight requires a certain minimum airspeed. This glides, straight-and-level flight, and from medium critical airspeed depends on certain factors, such as banked gliding and level flight turns. Slow flight at gross weight, load factors, and existing density altitude. approach speeds should include slowing the airplane The minimum speed below which further controlled smoothly and promptly from cruising to approach flight is impossible is called the stalling speed. An speeds without changes in altitude or heading, and important feature of pilot training is the development determining and using appropriate power and trim of the ability to estimate the margin of safety above the settings. Slow flight at approach speed should also stalling speed. Also, the ability to determine the include configuration changes, such as landing gear characteristic responses of any airplane at different and flaps, while maintaining heading and altitude. airspeeds is of great importance to the pilot. The student pilot, therefore, must develop this awareness in FLIGHT AT MINIMUM CONTROLLABLE order to safely avoid stalls and to operate an airplane AIRSPEED This maneuver demonstrates the flight characteristics correctly and safely at slow airspeeds. and degree of controllability of the airplane at its minimum flying speed. By definition, the term “flight SLOW FLIGHT at minimum controllable airspeed” means a speed at Slow flight could be thought of, by some, as a speed which any further increase in angle of attack or load that is less than cruise. -
Incorporation of Physics-Based Controllability Analysis in Aircraft
INCORPORATION OF PHYSICS-BASED CONTROLLABILITY ANALYSIS IN AIRCRAFT MULTI-FIDELITY MADO FRAMEWORK Dissertation Submitted to The School of Engineering of the UNIVERSITY OF DAYTON In Partial Fulfillment of the Requirements for The Degree of Doctor of Philosophy in Engineering By Christopher Meckstroth, M.S. Dayton, Ohio December 2019 INCORPORATION OF PHYSICS-BASED CONTROLLABILITY ANALYSIS IN AIRCRAFT MULTI-FIDELITY MADO FRAMEWORK Name: Meckstroth, Christopher Michael APPROVED BY: _________________________________ ________________________________ Raúl Ordóñez, Ph.D. Raymond Kolonay, Ph.D. Advisory Committee Chairman Committee Member Associate Professor Director Electrical and Computer Engineering Multidisciplinary Science and University of Dayton Technology Center AFRL/RQVC _________________________________ ________________________________ Eric Balster, Ph.D. Keigo Hirakawa, Ph.D. Committee Member Committee Member Associate Professor Associate Professor Electrical and Computer Engineering Electrical and Computer Engineering University of Dayton University of Dayton _________________________________ ________________________________ Robert J. Wilkens, Ph.D., P.E. Eddy M. Rojas, Ph.D., M.A., P.E. Associate Dean for Research and Innovation Dean, School of Engineering Professor School of Engineering ii ABSTRACT INCORPORATION OF PHYSICS-BASED CONTROLLABILITY ANALYSIS IN AIRCRAFT MULTI-FIDELITY MADO FRAMEWORK Name: Meckstroth, Christopher Michael University of Dayton Advisor: Dr. Raúl Ordóñez A method is presented to incorporate physics-based controllability -
A Study of the Design of Adaptive Camber Winglets
A STUDY OF THE DESIGN OF ADAPTIVE CAMBER WINGLETS A Thesis presented to the Faculty of California Polytechnic State University, San Luis Obispo In Partial Fulfillment of the Requirements for the Degree Master of Science in Aerospace Engineering by Justin Rosescu June 2020 © 2020 Justin Julian Rosescu ALL RIGHTS RESERVED ii COMMITTEE MEMBERSHIP TITLE: A Study of the Design of Adaptive Camber Winglets AUTHOR: Justin Rosescu DATE SUBMITTED: June 2020 COMMITTEE CHAIR: Paulo Iscold, Ph.D. Professor of Aerospace Engineering COMMITTEE MEMBER: David Marshall, Ph.D. Professor of Aerospace Engineering COMMITTEE MEMBER: Aaron Drake, Ph.D. Professor of Aerospace Engineering COMMITTEE MEMBER: Kurt Colvin, Ph.D. Professor of Industrial Engineering iii ABSTRACT A Study of the Design of Adaptive Camber Winglets Justin Julian Rosescu A numerical study was conducted to determine the effect of changing the camber of a winglet on the efficiency of a wing in two distinct flight conditions. Camber was altered via a simple plain flap deflection in the winglet, which produced a constant camber change over the winglet span. Hinge points were located at 20%, 50% and 80% of the chord and the trailing edge was deflected between -5° and +5°. Analysis was performed using a combination of three- dimensional vortex lattice method and two-dimensional panel method to obtain aerodynamic forces for the entire wing, based on different winglet camber configurations. This method was validated against high-fidelity steady Reynolds Averaged Navier-Stokes simulations to determine the accuracy of these methods. It was determined that any winglet flap deflections increased induced drag and parasitic drag, thus decreasing efficiency for steady level flight conditions. -
Investigating the Effects of Altitude and Flap Setting on the Specific Excess Power of a PA-28-161 Piper Warrior
Investigating the Effects of Altitude and Flap Setting on the Specific Excess Power of a PA-28-161 Piper Warrior By Tjimon Meric Louisy A thesis submitted to the College of Engineering and Science of Florida Institute of Technology In partial fulfillment of the requirements For the degree of Master of Science in Flight Test Engineering Melbourne, Florida December 2019 We the undersigned committee hereby approve the attached thesis, “Investigating the Effects of Altitude and Flap Setting on the Specific Excess Power of a PA-28-161 Piper Warrior”, by Tjimon Meric Louisy. _________________________________________________ Brian A. Kish, Ph.D. Assistant Professor Aerospace, Physics and Space Sciences Major Advisor _________________________________________________ Isaac Silver, Ph.D. Associate Professor College of Aeronautics _________________________________________________ Ralph Kimberlin, Dr. Ing Professor Aerospace, Physics and Space Sciences _________________________________________________ Daniel Batcheldor Professor and Department Head Aerospace, Physics and Space Sciences Abstract Investigating the Effects of Altitude and Flap Configuration on the Specific Excess Power of a PA-28-161 Piper Warrior Tjimon Meric Louisy Advisor: Brian A. Kish, Ph.D. The high number of General Aviation (GA) accidents attributed to Loss of Control suggests that GA pilots are lacking low speed awareness and are unable to appropriately recognize when the aircraft is in a low energy state. There is, therefore, an urgent need for the development of an energy management system which is applicable to GA aircraft that can alert the pilot in situations of low energy conditions and recommends to the pilot the appropriate corrective action to restore conditions to a safe energy state. This will require the development of an algorithm that governs this energy management system that considers a comprehensive understanding of the performance capabilities of GA aircraft, particularly the ability of the aircraft to progress from one energy state to another. -
Automobile Aerodynamics How It Applies to LFEV Project
Automobile Aerodynamics How it Applies to LFEV Project Brendan Malone Electrical and Computer Engineering Department Lafayette College Easton, PA 18042, USA [email protected] Abstract— This document will provide a brief overview about how automobile aerodynamics are applied. This paper will C. Prevent Aerodynamics Instability explain the basic terms and formulas that would affect the The last characteristic that the paper that will be discusses LFEV. has to do with automobile aerodynamics and its impact on aerodynamic instability and driving characteristics. This can Keywords— lift, thrust, drag, downforce, automobile, be split into two different sections that relate towards each aerodynamics other. The first goal is to prevent lift in the car because we do not want the car to begin to be airborne the second is to create I. INTRODUCTION a downforce which will allow for tighter turns. This document will address the purpose, factors, and modeling components of automobile aerodynamics. There are III. BASICS OF AERODYNAMICS multiple economic, social, and performance related reasons Aerodynamics is a branch of fluid dynamics that deals with that cause automobile aerodynamics to be important. These how air interacts with objects. The first major push in the study both apply to commercial and racing vehicles. With the range of aerodynamics began around flight. By taking advantage of of benefits the study of automobile aerodynamics is an aerodynamics scientist hoped to achieve flight with materials important field of study. These concepts will be applied to the that were heavier than air. This principle did not begin to be Lafayette College Formula Electric Vehicle in the following applied to automobiles until the 1920s. -
Aircraft Speed Impacts on Community Noise Report (Final) V13
Evaluation of the Impact of Transport Jet Aircraft Approach and Departure Speed on Community Noise Prof. R. John Hansman Jacqueline Thomas Report No. ICAT-2020-03 April 2020 MIT International Center for Air Transportation (ICAT) Department of Aeronautics & Astronautics Massachusetts Institute of Technology CambriDge, MA 02139 USA I. Introduction This report evaluates the impact of changing aircraft speeD During approach anD Departure on community noise for transport category jet aircraft. This analysis is part of a broader stuDy investigating the opportunities to moDify approach anD Departure proceDures to reDuce community noise impact. This report also adDresses a requirement in Section 179 of the FAA Reauthorization Act of 2018 (H.R. 302) to evaluate the relationship between jet aircraft approach anD takeoff speeDs anD corresponDing noise impacts on communities surrounDing airports. II. Impact of Speed on Aircraft Source Noise The primary sources of noise from aircraft are engine anD airframe noise, as shown in Fig. 1. Historically jet engine noise has been the Dominant noise source, particularly During high power settings on takeoff. Modern engines have become significantly quieter [1] anD airframe noise has become increasingly important During lanDing anD for some reDuceD power settings. Aircraft speed impacts engine anD airframe noise Differently, as discussed briefly below. Aircraft Noise Sources Engine Noise Airframe Noise Trailing Edge Fan Slats CombustionCore Flaps Jet Landing Gear Fig. 1 Primary Conventional Turbofan Aircraft Noise Sources Example breakDowns of the various noise components for a representative narrow-body jet transport aircraft after initial Departure anD on final approach are shown in Fig. 2. Engine noise is Dominant on Departure with most of the noise coming from the fan, followeD by the jet. -
Chapter 2: Aerodynamics of Flight
Chapter 2 Aerodynamics of Flight Introduction This chapter presents aerodynamic fundamentals and principles as they apply to helicopters. The content relates to flight operations and performance of normal flight tasks. It covers theory and application of aerodynamics for the pilot, whether in flight training or general flight operations. 2-1 Gravity acting on the mass (the amount of matter) of an object is increased the static pressure will decrease. Due to the creates a force called weight. The rotor blade below weighs design of the airfoil, the velocity of the air passing over the 100 lbs. It is 20 feet long (span) and is 1 foot wide (chord). upper surface will be greater than that of the lower surface, Accordingly, its surface area is 20 square feet. [Figure 2-1] leading to higher dynamic pressure on the upper surface than on the lower surface. The higher dynamic pressure on the The blade is perfectly balanced on a pinpoint stand, as you upper surface lowers the static pressure on the upper surface. can see in Figure 2-2 from looking at it from the end (the The static pressure on the bottom will now be greater than airfoil view). The goal is for the blade to defy gravity and the static pressure on the top. The blade will experience an stay exactly where it is when we remove the stand. If we do upward force. With just the right amount of air passing over nothing before removing the stand, the blade will simply fall the blade the upward force will equal one pound per square to the ground. -
Boundary Layer Theory Aerodynamics
Boundary Layer Theory Aerodynamics F. Mellibovsky Escola d'Enginyeria de Telecomunicaci´oi Aeroespacial de Castelldefels Universitat Polit`ecnicade Catalunya November 13, 2018 Summary Introduction Viscous Effects in Aerodynamics Drag Coefficient of Several Flows Shortcomings of Potential Flow Theory Laminar Boundary Layer Boundary Layer Hypothesis Equations & Solution Methods Turbulent Boundary Layer Transition & Turbulent Flows Equations & Solution Methods Boundary Layer Structure Extensions of Boundary Layer Theory Compressibility & Thermal Effects 3-Dimensional Boundary Layer Laminar-Turbulent Transition Bibliography Outline Introduction Viscous Effects in Aerodynamics Drag Coefficient of Several Flows Shortcomings of Potential Flow Theory Laminar Boundary Layer Boundary Layer Hypothesis Equations & Solution Methods Turbulent Boundary Layer Transition & Turbulent Flows Equations & Solution Methods Boundary Layer Structure Extensions of Boundary Layer Theory Compressibility & Thermal Effects 3-Dimensional Boundary Layer Laminar-Turbulent Transition Bibliography Viscous Effects in Aerodynamics 2 I Rate-of-change of fluid vol: ~u(~r + d~r) = ~u(~r) + ~u d~r + O( d~r ) r k k translation deformation (∇×~u)× z }| |{z} { z }| { 1 ~ 1 1 ~ 1 r~u = (r · ~u)~I + r~u + r~uT − (r · ~u)~I + r~u − r~uT 3 2 3 2 | {z } | {z } | {z } volume shear rotation translation volume change shear rotation Viscous Effects in Aerodynamics 2 I Rate-of-change of fluid vol: ~u(~r + d~r) = ~u(~r) + ~u d~r + O( d~r ) r k k translation deformation (∇×~u)× z }| |{z} { z }| {