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Design of a Controlled Descent Lifting Body Glider for High Altitude Payload Recovery

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Design of a Controlled Descent Lifting Body Glider for High Altitude Payload Recovery University of North Dakota UND Scholarly Commons Theses and Dissertations Theses, Dissertations, and Senior Projects January 2019 Design Of A Controlled Descent Lifting Body Glider For High Altitude Payload Recovery Nanette Valentour Follow this and additional works at: https://commons.und.edu/theses Recommended Citation Valentour, Nanette, "Design Of A Controlled Descent Lifting Body Glider For High Altitude Payload Recovery" (2019). Theses and Dissertations. 2870. https://commons.und.edu/theses/2870 This Thesis is brought to you for free and open access by the Theses, Dissertations, and Senior Projects at UND Scholarly Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of UND Scholarly Commons. For more information, please contact [email protected]. DESIGN OF A CONTROLLED DESCENT LIFTING BODY GLIDER FOR HIGH ALTITUDE PAYLOAD RECOVERY by Nanette Bassett Valentour Bachelor of Science, University of Cincinnati, 2016 A Thesis Submitted to the Graduate Faculty of the University of North Dakota in partial fulfillment of the requirements for the degree of Master of Science Grand Forks, North Dakota December 2019 l PERMISSION Title Design of a Controlled Descent Lifting Body Glider for High Altitude Payload Recovery Department Space Studies Degree Master of Science In presenting this thesis in partial fulfillment of the requirements for a graduate degree from the University of North Dakota, I agree that the library of this University shall make it freely available for inspection. I further agree that permission for extensive copying for scholarly purposes may be granted by the professor who supervised my thesis work or, in his absence, by the Chairperson of the department or the dean of the School of Graduate Studies. It is understood that any copying or publication or other use of this thesis or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of North Dakota in any scholarly use which may be made of any material in my thesis. Nanette Valentour November 9, 2018 iii ACKNOWLEDGMENTS I wish to express my sincere appreciation to my advisor and members of my advisory Committee for their guidance and support during my time in the master’s program at the University of North Dakota. iv ABSTRACT A lifting body scaled glider to be used as a recovery method for high altitude ballooning payloads has been developed at the University of North Dakota. Current recovery techniques for balloon payloads consist of monitoring and chasing the payload signal until it can be recovered. It is expected that a lifting body glider can reduce the distance for payload recovery and in some cases effectively return the payload back to the Ground Station. A preliminary subsonic aerodynamic model has been developed using MATLAB and the Vortex Lattice Method (VLM). Traditional evaluation techniques typical for calculation of the aerodynamic coefficients are not sufficient to predict the flight performance of the glider due to its fuselage lift contribution. Thus, two-dimensional panel methods along with the traditional three-dimensional VLM are used in conjunction to produce adequate results. The proposed computational model is expected to sufficiently estimate the subsonic aerodynamic characteristics of the glider to allow for the optimization of the geometry. The calculated loads will be used to design the structure of the glider, which is fabricated using composites and the appropriate resin. The glider will be integrated with a separately developed navigation system before undergoing a preliminary low altitude flight test for verification of the computational model and structural design. The aerodynamic coefficients will be compiled into functions which will be used in the MATLAB Aerospace Module and Simulink Blockset to create a robust model for simulation studies. The model must be developed such that the operator can simulate different flight paths and optimize the carrying capacity of the glider to support various payloads used for atmospheric experimentation. The resulting simulation will allow the user to analyze and trim the glider for various flight configurations depending on the location of the center of mass and the anticipated release altitude. For high altitude ballooning students unfamiliar with computational v aerodynamics, the simulation model will help the student to visualize how difficult or easy the glider would be to control under the current configuration. vi TABLE OF CONTENTS LIST OF FIGURES ........................................................................................................................... x LIST OF TABLES ......................................................................................................................... xvi LIST OF APPENDICES ............................................................................................................... xvii NOMENCLATURE .................................................................................................................... xviii ACKNOWLEDGEMENTS ............................................................................................................. iv ABSTRACT ...................................................................................................................................... v CHAPER 1. INTRODUCTION ........................................................................................................ 1 1.1 Statement of the Problem ................................................................................................ 1 1.2 Research Purpose ............................................................................................................ 1 CHAPTER 2. A REVIEW OF THE LITERATURE ........................................................................ 2 2.1 Previous Research ........................................................................................................... 2 2.2 Lifting Bodies .................................................................................................................. 2 2.3 Vortex Panel Methods ..................................................................................................... 3 CHAPTER 3. COMPUTATIONAL AERODYNAMIC MODELING ............................................ 6 3.1 Preliminary Aerodynamic Model Development ............................................................. 6 3.1.1 Implementing the Vortex Lattice Method ........................................................ 6 3.1.2 Adjusting for two-dimensional effects ........................................................... 12 3.2 Modeling the Lifting Body Geometry in MATLAB ..................................................... 17 3.2.1 Initial conditions ............................................................................................. 17 3.2.2 Solidworks Flow Simulation .......................................................................... 19 3.2.3 Developing the computational model ............................................................ 22 vii 3.2.4 Static Stability Analysis ................................................................................. 36 CHAPTER 4. LIFTING BODY GLIDER SIMULINK MODEL .................................................. 39 4.1 Preparing the Computational Data ................................................................................ 39 4.2 Airframe Model ............................................................................................................. 45 4.3 Dynamic Stability Analysis ........................................................................................... 53 4.3.1 Longitudinal Analysis .................................................................................... 56 4.3.2 Lateral Analysis ............................................................................................. 60 4.4 Flight Simulation ........................................................................................................... 62 4.4.1 FlightGear Aircraft Model Requirements ...................................................... 62 4.4.2 Running FlightGear with Simulink Models ................................................... 65 CHAPTER 5. STRUCTURAL DESIGN ........................................................................................ 68 5.1 Preliminary Calculations ............................................................................................... 68 5.1.1 Body and Wings ............................................................................................. 69 5.1.2 Control Surface Hinges .................................................................................. 75 5.2 Solidworks Static Structural Analysis .......................................................................... 77 CHAPTER 6. FABRICATION ....................................................................................................... 87 6.1 Foam Operations ........................................................................................................... 87 6.2 Materials ........................................................................................................................ 89 6.3 Methodology ................................................................................................................. 91 6.3.1 Molding Process ............................................................................................
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