Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"Plume-impingement"”.
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Simulation of rocket plume impingement and dust dispersal on the lunar surface
When a lander approaches a dusty surface, the plume from the descent engine impinges on the ground and entrains loose regolith into a high velocity spray. This problem exhibits a wide variety of complex phenomena such as highly under-expanded plume impingement, transition from continuum to free …
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Real-time quasi-analytical trajectory generation for docking with tumbling objects
… algorithms for this capability do not address plume impingement due to thrusters, which can lead to damage to the target object, and can require the use of nonlinear solvers that neither guarantee convergence of a solution nor be deployed in real-time using current computational capabilities of …
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Electromagnetic formation flight of satellite arrays
… by propellant include optical contamination, plume impingement, thermal emission, and vibration excitation. For those missions where control of relative degrees of freedom is important, we consider using a system of electromagnets, in concert with reaction wheels, to replace the consumables. A …
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Sensor Craft Control Using Drone Craft with Coulomb Propulsion System
The Coulomb propulsion system has no exhaust plume impingement problem with neighboring spacecraft and does not contaminate their sensors because it requires essentially no propellant. It is suitable to close formation control on the order of dozens of meters. The Coulomb forces are internal forces …
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A* Node Search and Nonlinear Optimization for Satellite Relative Motion Path Planning
… such as complex keep-out-regions and thruster plume impingement, that may be required for inspection of a specific target area in a complex environment. This work is widely applicable and can be expanded to apply to a variety of satellite relative motion trajectory planning problems.
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Trajectory optimization using mixed-integer linear programming
… or other vehicles and avoidance of thruster plumes from spacecraft. Assignment refers to the inclusion of decisions about terminal constraints in the optimization, such as assignment of waypoints to UAVs and the assignment of spacecraft to positions in a formation. These requirements lead to …
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Modeling Differential Charging of Composite Spacecraft Bodies Using the Coliseum Framework
… is a tool designed for electric propulsion plume interactions. Virginia Tech has been developing a module for COLISEUM called DRACO, a particle-in-cell based code capable of plume modeling for geometrically complex spacecraft. This work integrates a charging module into DRACO. Charge is …
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A Study of Dynamics and Stability of Two-Craft Coulomb Tether Formations
… formation shape and attitude while avoiding plume impingement issues. The relative distance between the two satellites can be increased or decreased using electrostatic Coulomb forces. The linear dynamics and stability analysis of such reconfiguration are studied for all the three …
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On the dynamics, navigation and control of a spacecraft formation of solar concentrators in the proximity of an asteroid
… proximity of the asteroid in order to avoid the plume impingement and the occultation from the asteroid itself. Issues regarding the contamination of the mirrors are addressed and compared with the simulated deflections predicted considering no contamination. Lastly, initial system mass budgets …
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Magma genesis beneath active continental rifts
… as evidence for anomalously hot mantle plumes actively rising from the deep mantle beneath both regions. However, in light of increasing evidence that these mantle structures may also be chemical in nature, alternative explanations highlight the role of heterogeneous, easily-fusible …