Some High Alpha and Handling Qualities Aerodynamics
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Wind Tunnel Analysis and Flight Test of a Wing Fence on a T-38
Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 3-6-2009 Wind Tunnel Analysis and Flight Test of a Wing Fence on a T-38 Michael D. Williams Follow this and additional works at: https://scholar.afit.edu/etd Part of the Aerodynamics and Fluid Mechanics Commons Recommended Citation Williams, Michael D., "Wind Tunnel Analysis and Flight Test of a Wing Fence on a T-38" (2009). Theses and Dissertations. 2407. https://scholar.afit.edu/etd/2407 This Thesis is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. WIND TUNNEL ANALYSIS AND FLIGHT TEST OF A WING FENCE ON A T-38 THESIS Michael D. Williams, Major, USAF AFIT/GAE/ENY/09-M20 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The views expressed in this thesis are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government. AFIT/GAE/ENY/09-M20 WIND TUNNEL ANALYSIS AND FLIGHT TEST OF A WING FENCE ON A T-38 THESIS Presented to the Faculty Department of Aeronautical and Astronautical Engineering Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Master of Science in Aeronautical Engineering Michael D. -
Selected Structural Elements of the Wing to Increase the Lift Force
I efektywność transportu Ernest Gnapowski Selected structural elements of the wing to increase the lift force JEL: L93 DOI: 10.24136/atest.2018.494 Data zgłoszenia: 19.11.2018 Data akceptacji: 15.12.2018 The article presents a currently used structural elements to increase the lift force. Presented mechanical and no-mechanical construction elements that increase the lifting force. The author's attention to the new direction of flow control using a DBD plasma actuator. This is a new direction of active flow control. Słowa kluczowe: aerodynamic, high-lift device, plasma actuator DBD Introduction One of the many causes of accidents and disasters in aviation is Fig. 1. The most common airline profiles; a) symmetrical, b) semi- a loss of lift force during flight, most often caused by flow disturb- symmetrical, c) flat bottomed, d) under-cambered ances around a wing profile. This is especially true when starting or landing, the wing operates in the limiting angles of attack. There Even a properly selected wing profile in certain conditions (at may be a stall and catastrophic disturbance of the flight path. high angles of attack) loses the lift force. To counteract this, con- Wing profiles have a specific geometry that determines the use struction offices introduce elements that improve the flow laminarity of a particular profile in aircraft constructions. The parameters which and improve safety. influence the choice of the design of the profile are; speed of flight, wing loading, purpose aircraft. Each airfoil has determined experi- Wing cuff mentally or by calculation the maximum angle of attack α and the Wing cuff is a static aerodynamic modification of the front part of minimum speed at which no loss of aerodynamic lift. -
The Effect of Slot Configuration on Active Flow Control Performance of Swept Wings At
The Effect of Slot Configuration on Active Flow Control Performance of Swept Wings at Low Reynolds Numbers Thesis Presented in Partial Fulfillment of the Requirements for Graduation with Honors Research Distinction in Aeronautical and Astronautical Engineering at The Ohio State University By Ali N. Hussain B.S. Program in Aeronautical and Astronautical Engineering The Ohio State University Department of Mechanical & Aerospace Engineering April 2018 Thesis Committee Dr. Jeffrey P. Bons, Advisor Dr. Clifford Whitfield, Committee Member © Copyright by Ali N. Hussain 2018 2 Abstract Active flow control (AFC) in the form of a discrete wall normal slot was investigated on a NACA 643-618 laminar wing model. The wing model has a leading-edge sweep of (Λ = 30°) and tests were performed using a chordwise Reynolds number of 100,000 with specific focus on the stall characteristics and performance of AFC while reducing energy needs. The study included comparing a segmented slot to a single continuous slot as well as the positioning of the slot itself along the chord at a spanwise location of z/b = 70%. For an Aeff/A of 0.5 (as compared to the original slot) maximum lift performance improved 9.6% for multiple slots while a single slot improved the maximum lift by 8.3% over the baseline. Surface flow visualization using tufts revealed that a single slot is much more effective at stopping spanwise flow and delaying stall to a higher angle of attack by 4°. For an Aeff/A of 0.75 (as compared to the original slot), lift performance improved 15.6% and 16.2% by covering x/c = 25% of the slot on the pressure and suction side of the airfoil, respectively. -
Semiempirical Simulation of Contemporary Fighter Planes
| Mathematics | UDC 629.735.33.015.075 Zhelonkin M. V. Semiempirical simulation of contemporary fighter planes engaging in dogfight in order to estimate the possibility of using supermanoeuvrability modes The paper presents investigation results concerning employing supermanoeuvrability modes in dogfight. We selected one of the standard manoeuvres and demonstrated the efficiency of using it. Keywords: features, supermanoeuvrability, dogfight, semi-empirical simulation, tactical employment, Split S manoeuvre. Introduction of attack, which lead to intense deceleration of Fighter aviation is mostly used for dogfighting the aircraft and to a decrease in energy height, and one of the main tasks of preparation for en- therefore a Split S manoeuvre will compensate gaging enemy air targets is the training of flight such a decrease to some extent. personnel in operating fighter aircraft weapons in Thus, in order to evaluate the efficiency of order to achieve the best performance to destroy supermanoeuvrability modes, we have selected enemy aircraft during dogfighting in various a Split S manoeuvre. Fig. 1 shows the aircraft weather and operational conditions when acting flight path when making the manoeuvre. solo or as part of an aircraft group. Modern 4++ The most important parameter that defines and 5th generation fighters are able to fly in a su- tolerable conditions for making a Split S man- permanoeuvrability mode, i.e. at angles of attack oeuvre is minimum altitude loss during the ma- beyond stall while maintaining balanced control. noeuvre, which depends on the entry speed and That is why flight personnel need to be properly altitude, as well as on the current g-load and air- trained in order to use all the aircraft capabilities. -
NASA Technical Memorandum 102629
NASA Technical Memorandum 102629 QUALITATIVE EVALUATION OF A CONFORMAL VELOCITY VECTOR DISPLAY FOR USE AT HIGH ANGLES-OF-ATTACK IN FIGHTER AIRCRAFT DENISE R. JONES JAMES R. BURLEY II JUNE 1990 (NA_A-F_-10752_) .._tJALITATIVL i_VALLIATIjN I-!F A L.'_;_:,JPi,!,_.L V_Lr)CI'IV VLzfi[i!K ,..;[SPLAY l--,.}E US.'_- AT _IGH A_C, LzS-OF-ATTACK IN FIuHI-_H, AIRCRAFT (NASA) i1 D L;SCL Oi.r, National Aeronautics and Space Administration Langley Research Center Hampton, Virginia 23665-5225 SUMMARY A piloted simulation study has been conducted in the Langley Differential Maneuvering Simulator (DMS) to evaluate the utility of a display device designed to illustrate graphically and conformally the approximate location of a fighter aircraft's velocity vector. The display device consisted of two vertical rows of light- emitting diodes (LED's) located toward the center of the cockpit instrument panel, with one row of lights visible to the left of the control stick and the other row visible to the right of the control stick. The light strings provided a logical extension of the head-up display (HUD) velocity vector symbol at flight-path angles which exceeded the HUD field-of-view. Four test subjects flew a modified F/A-18 model with this display in an air-to-air engagement task against an equally capable opponent. Their responses to a questionnaire indicated that the conformal velocity vector information could not be used during the scenarios investigated due to the inability to visually track a target and view the lights simultaneously. INTRODUCTION During the course of fighter aircraft display format research, many pilots have expressed a desire to have the direction in which the aircraft is traveling (aircraft's velocity vector) presented in the cockpit. -
General Aviation Aircraft Design
Contents 1. The Aircraft Design Process 3.2 Constraint Analysis 57 3.2.1 General Methodology 58 1.1 Introduction 2 3.2.2 Introduction of Stall Speed Limits into 1.1.1 The Content of this Chapter 5 the Constraint Diagram 65 1.1.2 Important Elements of a New Aircraft 3.3 Introduction to Trade Studies 66 Design 5 3.3.1 Step-by-step: Stall Speed e Cruise Speed 1.2 General Process of Aircraft Design 11 Carpet Plot 67 1.2.1 Common Description of the Design Process 11 3.3.2 Design of Experiments 69 1.2.2 Important Regulatory Concepts 13 3.3.3 Cost Functions 72 1.3 Aircraft Design Algorithm 15 Exercises 74 1.3.1 Conceptual Design Algorithm for a GA Variables 75 Aircraft 16 1.3.2 Implementation of the Conceptual 4. Aircraft Conceptual Layout Design Algorithm 16 1.4 Elements of Project Engineering 19 4.1 Introduction 77 1.4.1 Gantt Diagrams 19 4.1.1 The Content of this Chapter 78 1.4.2 Fishbone Diagram for Preliminary 4.1.2 Requirements, Mission, and Applicable Regulations 78 Airplane Design 19 4.1.3 Past and Present Directions in Aircraft Design 79 1.4.3 Managing Compliance with Project 4.1.4 Aircraft Component Recognition 79 Requirements 21 4.2 The Fundamentals of the Configuration Layout 82 1.4.4 Project Plan and Task Management 21 4.2.1 Vertical Wing Location 82 1.4.5 Quality Function Deployment and a House 4.2.2 Wing Configuration 86 of Quality 21 4.2.3 Wing Dihedral 86 1.5 Presenting the Design Project 27 4.2.4 Wing Structural Configuration 87 Variables 32 4.2.5 Cabin Configurations 88 References 32 4.2.6 Propeller Configuration 89 4.2.7 Engine Placement 89 2. -
Design, Analyses, and ,. Simulation Results
NASA Technical Paper 3446 _:i,2 _ .,/, ! High-Alpha Research Vehicle (HARV) Longitudinal Controller: Design, Analyses, and ,. Simulation Results Aaron J. Ostroff Langley Research Center • Hampton, Virginia Keith D. Hoffler ViGYAN, Inc. • Hampton, Virginia Melissa S. Proffitt Lockheed Engineering & Sciences Company • Hampton, Virginia :' National Aeronautics and Space Administration Langley Research Center • Hampton, Virginia 23681-0001 • : J July 1994 /: The use of trademarks or names of manufacturers in this i! report is for accurate reporting and does not constitute an official endorsement, either expressed or implied, of such products or manufacturers by the National Aeronautics and Space Administration. Acknowledgment The authors wish to acknowledge the following individuals who made important contributions to the research described in this paper: Philip W. Brown, Michael R. Phillips, and Robert A. Rivers, all from NASA Langley Research Center, who served as test pilots and provided ratings and insightful comments for the piloted simulation tasks. Michael D. Messina, Lockheed Engineering & Sciences Company, Hampton, VA, who maintained the nonlinear batch simulation and organized test cases for transportingreal-time code. Susan W. Carzoo, Unisys Corporation, who maintained the real- time software for the piloted simulation. Dr. Barton J. Bacon, NASA Langley Research Center, who constructed and tested the real-lt algorithms used for robustness analysis. John V. Foster, NASA Langley Research Center, who performed some engineering-test -
22. Maneuvering at High Angle and Rate
12/3/18 Maneuvering at High Angles and Angular Rates Robert Stengel, Aircraft Flight Dynamics MAE 331, 2018 Learning Objectives • High angle of attack and angular rates • Asymmetric flight • Nonlinear aerodynamics • Inertial coupling • Spins and tumbling Flight Dynamics 681-785 Airplane Stability and Control Chapter 8 Copyright 2018 by Robert Stengel. All rights reserved. For educational use only. http://www.princeton.edu/~stengel/MAE331.html 1 http://www.princeton.edu/~stengel/FlightDynamics.html Tactical Airplane Maneuverability • Maneuverability parameters – Stability – Roll rate and acceleration – Normal load factor – Thrust/weight ratio – Pitch rate – Transient response – Control forces • Dogfights – Preferable to launch missiles at long range – Dogfight is a backup tactic – Preferable to have an unfair advantage • Air-combat sequence – Detection – Closing – Attack – Maneuvers, e.g., • Scissors • High yo-yo – Disengagement 2 1 12/3/18 Coupling of Longitudinal and Lateral-Directional Motions 3 Longitudinal Motions can Couple to Lateral-Directional Motions • Linearized equations have limited application to high-angle/high-rate maneuvers – Steady, non-zero sideslip angle (Sec. 7.1, FD) – Steady turn (Sec. 7.1, FD) – Steady roll rate " F FLon % F = $ Lon Lat−Dir ' $ FLat−Dir F ' # Lon Lat−Dir & Lon Lat−Dir FLat−Dir , FLon ≠ 0 4 2 12/3/18 Stability Boundaries Arising From Asymmetric Flight Northrop F-5E NASA CR-2788 5 Stability Boundaries with Nominal Sideslip, βo, and Roll Rate, po NASA CR-2788 6 3 12/3/18 Pitch-Yaw Coupling Due To Steady -
Explaining Chemical Reactions
On the Use of Active Flow Control to Trim and Control a Tailles Aircraft Model Item Type text; Electronic Thesis Authors Jentzsch, Marvin Patrick Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 07/10/2021 06:46:41 Link to Item http://hdl.handle.net/10150/625917 ON THE USE OF ACTIVE FLOW CONTROL TO TRIM AND CONTROL A TAILLES AIRCRAFT MODEL by Marvin Jentzsch ____________________________ Copyright Marvin Jentzsch 2017 A Thesis Submitted to the Faculty of the DEPARTMENT OF AEROSPACE AND MECHANICAL ENGINEERING In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE WITH A MAJOR IN AEROSPACE ENGINEERING In the Graduate College THE UNIVERSITY OF ARIZONA 2017 2 STATEMENT BY AUTHOR The thesis titled On the Use of Active Flow Control to Trim and Control a Tailless Aircraft Model prepared by Marvin Jentzsch has been submitted in partial fulfillment of requirements for a master’s degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that an accurate acknowledgement of the source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. -
The Effect of Passive and Active Boundary-Layer Fences on Delta Wing Performance at Low Reynolds Number
Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 3-2020 The Effect of Passive and Active Boundary-layer Fences on Delta Wing Performance at Low Reynolds Number Anna C. Demoret Follow this and additional works at: https://scholar.afit.edu/etd Part of the Aerodynamics and Fluid Mechanics Commons Recommended Citation Demoret, Anna C., "The Effect of Passive and Active Boundary-layer Fences on Delta Wing Performance at Low Reynolds Number" (2020). Theses and Dissertations. 3213. https://scholar.afit.edu/etd/3213 This Thesis is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. THE EFFECT OF PASSIVE AND ACTIVE BOUNDARY-LAYER FENCES ON DELTA WING PERFORMANCE AT LOW REYNOLDS NUMBER THESIS Anna C. Demoret, Second Lieutenant, USAF AFIT-ENY-MS-20-M-258 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. The views expressed in this document are those of the author and do not reflect the official policy or position of the United States Air Force, the United States Department of Defense or the United States Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT-ENY-MS-20-M-258 THE EFFECT OF PASSIVE AND ACTIVE BOUNDARY-LAYER FENCES ON DELTA WING PERFORMANCE AT LOW REYNOLDS NUMBER THESIS Presented to the Faculty Department of Aeronautics and Astronautics Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command in Partial Fulfillment of the Requirements for the Degree of Master of Science in Aeronautical Engineering Anna C. -
00002-X Challenges in High-Alpha Vehicle
Pergan~,on Prog. Aerospace ScL Vol. 31, pp. 291-334, 1995 Copyright © 1995 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0376-0421(95)00002-X 0376-0421/95 $29.00 CHALLENGES IN HIGH-ALPHA VEHICLE DYNAMICS Lars E. Ericsson Engineering Consultant, Mountain View, California, U.S.A. Abstract--The evolution of aerospace vehicles towards ever-increasing maneuverability, including flight at high angles of attack and vehicle motions of large amplitudes and high angular rates, has led to the need for prediction of veh:Lcleaerodynamics that are dominated by unsteady separated flow effects. The existing data base is reviewed lo determine to what degree the following critical issues are understood: 1. Cause and effect of asymmetric fo:~ebody flow separation with associated vortices. 2. Cause of slender wing rock. 3. Effect of vehicle motion on dynamic airfoil stall. 4. Extrapolation from subscale tests to full-scale free flight. To extend the present knowledge to include the coupling existing between novel aerodynamic controls and the vehicle dynamics is the challenge facing designers of future agile aircraft operating at high angles of attack. CONTENTS NOTATION 1. INTRODUCTION 292 2. ASYMMETI~:IC FOREBODY FLOW SEPARATION 292 2.1. Introduction 292 2.2. Yaw characteristics 294 2.2.1. Moving wall effects 295 2.2.2. Flat spin 296 2.2.3. Reversal of coning motion 300 2.3. Roll characteristics 300 2.3.1. Dynamic forebody/leading-edge vortex interaction 301 2.4. Summary 306 3. SLENDER WING ROCK 306 3.1. Introduction 306 3.2. Recent e~perimental results and discussion 307 3.3. -
Commercial Aircraft Performance Improvement Using Winglets
Nikola N. Gavrilović Commercial Aircraft Performance Graduate Research Assistant Improvement Using Winglets University of Belgrade Faculty of Mechanical Engineering Aerodynamic drag force breakdown of a typical transport aircraft shows Boško P. Rašuo that lift-induced drag can amount to as much as 40% of total drag at Full Professor cruise conditions and 80-90% of the total drag in take-off configuration. University of Belgrade Faculty of Mechanical Engineering One way of reducing lift-induced drag is by using wing-tip devices. By applying several types of winglets, which are already used on commercial George S. Dulikravich airplanes, we study their influence on aircraft performance. Numerical Full Professor investigation of five configurations of winglets is described and Florida International University preliminary indications of their aerodynamic performance are provided. Department of Mechanical and Materials Engineering, Miami, Florida, USA Moreover, using advanced multi-objective design optimization software an optimal one-parameter winglet configuration was detrmined that Vladimir Parezanović simultaneously minimizes drag and maximizes lift. Researcher Institute PPRIME, CNRS UPR3346 Poitiers, France Keywords: Winglet, Bionics, Computational fluid dynamics, Drag reduction, Lift-induced drag, Optimization 1. INTRODUCTION of soaring birds and their use of tip feathers to control flight, continued on the quest to reduce induced drag The main motivation for using wingtip devices is and improve aircraft performance and further develop reduction of lift-induced drag force. Environmental the concept of winglets in the late 1970s [4]. This issues and rising operational costs have forced industry research provided a fundamental knowledge and design to improve efficiency of commercial air transport and approach required for extremely attractive option to this has led to some innovative developments for improve aerodynamic efficiency of civilian aircraft, reducing lift-induced drag.