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Solar Orbit Transfer Vehicle June 1, 2001 Solar Orbit Transfer Vehicle June 1, 2001 Christopher D. Hall, Associate Professor Department of Aerospace and Ocean Engineering Virginia Polytechnic Institute and State University Blacksburg, VA 24061 (540) 231-2314 (540) 231-9632 (FAX) [email protected] Heat Launch to LEO Mechanism graphite 300 km altitude Deployment block to Wait for 28 ° inclination Inflate 2400 K command collector 1 ½ hours 2 hours 11 ½ hours Continuous 01 234561718 19 Approximate 1 hour Continuous Continuous mission time Establish Perform Check telemetry in hours communication station-keeping data link operations as Ensure proper necessary subsystem Balance operation disturbance torques SOLAR ORBIT TRANSFER VEHICLE Submitted By: Nicholas Cummings Kevin Earle Douglas Klingemann Michael Nakles Andrew Pollard Ross Stilling Clinton Stone Eric Van Veldhuizen Richard Winski Emily Woodward Aerospace and Ocean Engineering Department Virginia Polytechnic Institute and State University Blacksburg, Virginia 3 May 2001 Professor: Dr. Christopher Hall Table of Contents Symbols.........................................................................................................................................................v Abbreviations...............................................................................................................................................ix List of Figures..............................................................................................................................................xi List of Tables .............................................................................................................................................xiii Chapter 1: Introduction .................................................................................................................................1 1.1 Request For Proposal ..........................................................................................................................1 1.2 Background.........................................................................................................................................2 Chapter 2: Solar Orbit Transfer Vehicle .......................................................................................................4 2.1 Overview.............................................................................................................................................4 2.2 Modeling.............................................................................................................................................5 2.3 Performance ......................................................................................................................................13 2.4 Operations.........................................................................................................................................15 2.5 Summary...........................................................................................................................................16 Chapter 3: Solar Collector...........................................................................................................................18 3.1 Overview...........................................................................................................................................18 3.2 Collector Design Considerations.......................................................................................................18 3.3 Solar Collector Subsystem Description ............................................................................................19 3.4 Mathematical Modeling ....................................................................................................................21 3.5 Deployment, Inflation, and Pressurization........................................................................................23 3.6 Summary and Further Research........................................................................................................24 Chapter 4: Solar Thermal Engine and Propulsion.......................................................................................25 4.1 Introduction.......................................................................................................................................25 4.2 Overview...........................................................................................................................................26 4.3 Modeling...........................................................................................................................................27 4.3.1 Heat Transfer..............................................................................................................................27 4.3.2 Orbital Motion............................................................................................................................29 4.3.3 Alternative Transfers..................................................................................................................30 4.3.4 Propellant Feed System..............................................................................................................30 4.4 Performance ......................................................................................................................................31 4.5 Summary...........................................................................................................................................31 4.6 Next Steps .........................................................................................................................................31 Chapter 5: Thermal .....................................................................................................................................33 5.1 Thermal system design......................................................................................................................33 ii 5.2 Fuel tank............................................................................................................................................33 5.3 Receiver/Cavity Design ....................................................................................................................36 5.4 Insulation...........................................................................................................................................37 5.4.1 Engine performance ...................................................................................................................37 5.5 Conclusions.......................................................................................................................................40 Chapter 6: Fuel Tank/Primary Structure.....................................................................................................41 6.1 Overview...........................................................................................................................................41 6.2 Hardware...........................................................................................................................................41 6.3 Modeling...........................................................................................................................................41 6.3.1 Monocoque Design ....................................................................................................................44 6.3.2 Applied and Equivalent Axial Loads .........................................................................................45 6.3.3 Sizing for Tensile Strength.........................................................................................................46 6.3.4 Sizing for Stability (Compressive Strength) ..............................................................................46 6.3.5 Internal Pressure.........................................................................................................................47 6.3.6 Mass and Volume of Monocoque Tank.....................................................................................47 6.3.7 Skin-Stringer Design..................................................................................................................48 Chapter 7: Attitude Determination and Control..........................................................................................51 7.1 Overview...........................................................................................................................................51 7.1.1 Background ................................................................................................................................51 7.1.2 Requirements .............................................................................................................................54 7.2 Hardware Examples ..........................................................................................................................55 7.2.1 Attitude Control .........................................................................................................................55 7.2.2 Attitude Determination: .............................................................................................................57 7.3 Modeling and Performance...............................................................................................................58 7.3.1 Modeling ....................................................................................................................................58
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