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 20 of 23 for “"slosh"”.
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Slosh Damping with Floating Magnetoactive Micro-Baffles
<p>Liquid sloshing within propellant tanks of launch vehicles and other major vehicles has been a major concern. Various methods have been utilized for the damping of slosh through Propellant Management Devices (PMD) accomplishing a wide range of results. Exploratory research conducted at the …
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Liquid Slosh Analysis Using Smoothed Particle Hydrodynamics
… algorithms as an adequate means for propellant slosh simulations in 1g and 0g environments. The dualSPHysics solver has been adapted for propellant slosh simulations. Simulated sloshing liquid frequency and damping ratio data for 1g cases has been compared to existing experiments for both …
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Motion Control of Open Containers with Slosh Constraints
[abstract missing]
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Development and Implementation of the SPHERES-Slosh Experiment
Understanding fluid slosh in a microgravity environment has the potential to make liquid-fueled spacecraft more effective. The SPHERES-Slosh Experiment gathers benchmarking data that can be used to validate computational fluid dynamics models for microgravity environments. This thesis discusses the …
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Modeling and Parameter Estimation of Spacecraft Lateral Fuel Slosh
<p>Predicting the effect of fuel slosh on spacecraft and launch vehicle attitude control systems has been a very important and challenging task and has been the subject of considerable research over the past years. Analytic determination of the slosh analog parameters has been met with mixed …
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Parameter Estimation of Spacecraft Fuel Slosh Using Pendulum Analogs
… For analytical prediction of the NTC, fuel slosh is often modeled using simple mechanical analogs such as pendulums or rigid rotors coupled to the spacecraft. Identifying model parameter values which adequately represent the sloshing dynamics is the most important step in obtaining a good …
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Nutation in the spinning SPHERES spacecraft and fluid slosh
… mainly unsuccessful and physical tests to gather slosh data have only been done for a few specific spacecraft. Data from past spacecraft is subject to a number complex physical factors and anomalies during the launch or mission. This study verifies a ground based method to test fluid tanks …
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Study of Hybrid Magneto-Active Propellant Management Device for Slosh Damping
<p>Sloshing of liquid upon the application of an external force is a natural phenomenon as the free surface is allowed to move without any constraints. Study of slosh is an ongoing research for many decades and many novel inventions in Propellant Management Devices (PMDs) such as the rigid baffles …
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Toward a full aircraft model platform for fuel slosh-structure interaction simulations
… models (ROMs). These are mainly structural, slosh and aerodynamic loads. This study focused on the structural and slosh aspects using Ele- mental(TM) software as the base. First, a structural ROM was developed such that it is compatible with Airbus data and processes. The developed code reads …
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Design of an Attitude Control System for a Spacecraft with Propellant Slosh Dynamics
<p>The presence of propellant slosh dynamics in a spacecraft system during a maneuver leads to attitude control system (ACS) performance degradation resulting in attitude tracking errors and instability. As spacecraft missions become more complex and involve longer durations, a substantial …
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An Algebraic Volume of Fluid Method for Strongly Coupled Spacecraft Fuel Slosh Modelling
… vehicle simulation is the prediction of fuel slosh loads during in-orbit manoeuvres, particularly due to the large fuel-to-solid mass ratios involved. To this end, this thesis details a high resolution mathematical model capable of predicting the dynamic interaction between fuel slosh and the …
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Experimental Investigation and CFD Simulation of Active Damping Mechanism for Propellant Slosh in Spacecraft Launch Systems
… of the launch vehicle is known as propellant slosh. If unchecked, propellant slosh can reach resonance and lead to complete loss of the spacecraft stability, it can change the trajectory of the vehicle or increase consumption of propellant from the calculated requirements, thereby causing …
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Maneuvering Control of a Spacecraft with Propellant Sloshing
<p>Propellant slosh has been a problem studied in spacecraft designs since the early days of large, liquid-fuel rockets. The conventional design solution involves physical structures inside the fuel tanks that limit propellant motion. Although effective, baffles and bladders add to spacecraft mass …
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The constrained discrete-time state-dependent Riccati equation technique for uncertain nonlinear systems
… filled fuel tank, assumed to have the first fuel slosh mode. The proposed robust CD-SDRE controller is then applied to the spacecraft attitude control system to stabilize its motion in the presence of uncertainties characterized by the first fuel slosh mode. The performance of the robust CD-SDRE …
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Dynamics and Control of Higher-order Nonholonomic Systems
… feedback, including space vehicles with multiple slosh modes and Prismatic-Prismatic-Revolute (PPR) robots moving open liquid containers, as well as an interesting class of systems that do not admit asymptotically stabilizing continuous static or dynamic state feedback. Specific assumptions are …
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Adaptive Control for Nonlinear, Time Varying Systems
… be caused by varying inertia resulting from fuel slosh or settling in a tank. The direct adaptive controller can also respond to external disturbances and unmodeled or nonlinear dynamics. Simulation results are presented for a prototype system that consists of two rotating tanks with time varying …
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Reduced order models for fluid-structure interaction systems by mixed finite element formulation
… forces are introduced to include the coupled sloshing mode. In addition, u/p mixed formulation is the first time employed in solid. The numerical examples will demonstrate that the mixed formulations are capable of predicted coupled frequencies and mode shapes even if primary slosh, …
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The vulnerability of U.S. coastal energy infrastructure under climate change
… from hurricane runs from each model to the SLOSH model (Sea, Lake and Overland Surges from Hurricanes) (19) to investigate the change in frequency and distribution of surge heights across climates. Further, we incorporate uncertainty surrounding the magnitude of sea level rise and …
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High-speed video observation and on-line measurements of oil aeration in an internal combustion engine
… on the free surface caused the surface to slosh at the frequency of the crankshaft's rotation. Foam was observed to form above a threshold speed and a threshold temperature. The windage tray was observed to reduce the droplet number density. When the windage tray was removed, the increased …
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Stability analysis of partially filled tanker trucks using a finite element modeling approach
… the liquid load shift caused by fluid slosh amplifies the propensity of these vehicles to rollover.;This research presents an approach for determining the threshold of rollover stability of a specific tanker truck by using finite element analysis methods, specifically the software …
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