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Showing 1 to 16 of 16 for “"Thrust efficiency"”.
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Performance testing and internal probe measurements of a high specific impulse Hall thruster
The BHT-1000 high specific impulse Hall thruster was used for performance testing and internal plasma measurements to support the ongoing development of computational models. The thruster was performance tested in both single and two stage anode configurations. In the single stage configuration, …
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Theoretical and experimental investigation of Hall thruster miniaturization
… the area of formation flight. Miniaturized Hall thrusters have been identified as a candidate for lightweight, high specific impulse propulsion systems that can extend mission lifetime and payload capability. A set of scaling laws was developed that allows the dimensions and operating parameters …
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Optimization of Harmonically Deforming Thin Airfoils and Membrane Wings for Optimum Thrust and Efficiency
… and numerical approaches to optimizing thrust and thrust efficiency of harmonically deforming thin airfoils and membrane wings. A frequency domain unsteady aerodynamic theory for deformable thin airfoils, with Chebychev polynomials as the basis functions is presented. Stroke-averaged …
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Microthruster Experimental Analysis
… that could accurately test and measure the thrust efficiency of conical shaped microthrusters with varying divergence half angles. The experimental apparatus measured the thrust of micronozzles for various feed pressures in vacuum (to duplicate in space operation) as well as ambient. …
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Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles
… the optimizations involved the maximization of thrust efficiency, the minimization of fuel mass consumption, and the minimization of exergy destruction plus fuel exergy loss. The principal results found the minimum fuel consumption and minimum exergy destruction measures equivalent, both meeting …
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Microthrusters based on the T5 and T6 hollow cathodes
… the development of a low power, low cost microthruster able to offer propellant savings over conventional alternatives and enable higher energy missions. Such a thruster would also be beneficial in the development of all-electric spacecraft whereby the normally separate reaction control system …
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A CFD Investigation of Axisymmetric Microthruster Nozzles for Use on Nano-Satellites
<p>The performance of microthruster nozzles (^ 0.1 N thrust) depending on nozzle contour, propellant and surroundings, destined for use in nanosatellite missions, is investigated via a numerical approach using the Wind-US flow solver. An experimental apparatus designed to measure microthruster …
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Propulsion mechanisms in a helicon plasma thruster
Electric thrusters offer an attractive option for various in-space propulsion tasks due to their high thrust efficiencies. The performance characteristics of a compact electric thruster utilizing a helicon plasma source is investigated with the goal of identifying potential thrust mechanisms. …
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A computational and experimental investigation of the propulsive and lifting characteristics of oscillating airfoils and airfoil combinations in incompressible flow
… with the modified computer code, U2DIFF. thrust, efficiency, and phase relationships were computed and compared to existing theoretical results. Furthermore, to help understand the dynamic stall process, relationships were developed between steady and quasi-steady pressure distributions …
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Two-dimensional numerical modeling of Radio-Frequency ion engine discharge
… scaling penalties. Of high-performance plasma thrusters, the radio-frequency ion engine is most likely to succeed in scaling as it does not require an externally applied magnetic field and is structurally simple to construct. As part of a design package an original two-dimensional simulation …
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The design and feasibility of a 10 mN chemical space propulsion thruster
… to the community. The nozzle's coefficient of thrust efficiency is approximately 80% for Reynolds numbers greater than a 1,000 and the data suggest the efficiency drops below 50% at 200. The error becomes significant at low Reynolds number due to pressure measurement error, which reduces the …
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Using H2 to supplement Diesel in Marine Applications
… with hydrogen. A basic analysis of the brake efficiency, or propeller thrust efficiency, was carried out and it was found that the dual firing of the test engine with hydrogen and diesel achieved the best efficiencies at medium to high loads, which is the typical working range for these types …
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Multi-body Dynamics Simulation and Analysis of Wave-adaptive Modular Vessels
Catamarans provide vast deck space, high thrust efficiency, and excellent transverse stability, however, in rough conditions they can be susceptible to deck slamming from head seas or bow diving in following seas and a pitch-roll coupling effect that can lead to uncomfortable corkscrew motion under …
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A fully microfabricated two-dimensional electrospray array with applications to space propulsion
… of a fully-integrated planar electrospray thruster array, which could lead to more efficient and precise thrusters for space propulsion applications. The same techniques could be used for making arrays to increase throughput in many other electrospray applications. Electrospray thrusters …
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An exploration of prominent cusped-field thruster phenomena : the hollow conical plume and anode current bifurcation
A low power plasma thruster, initially dubbed the Diverging Cusped-Field Hall Thruster, was built at MIT in 2007 with the aim of providing an alternative to comparably sized conventional Hall thrusters able to provide enhanced lifetimes and thus deliver higher total impulses. The initial design was …
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A Computational Framework for Dimensionally Reduced Particle Dynamics in Magnetic Nozzle Fields: An Adiabatic Invariant Approach
This thesis investigates a dimensional reduction strategy for modeling charged particle trajectories in electromagnetic fields representative of magnetic nozzle expansion regions. By employing Julia’s DifferentialEquations.jl and Python’s scientific libraries, particle trajectories are integrated …