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Showing 1 to 19 of 19 for “"plasma plume"”.
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Computational modeling of a Hall thruster plasma plume in a vacuum tank
… integration is uncertainty about the thruster plume's interaction with spacecraft components. While in-space data is difficult to collect, much experimental data from vacuum tank tests is readily available. Effectively taking advantage of this wealth requires understanding of the effects from …
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A kinetic transport model of uranium molecular species formation in a laser ablated plasma plume
… tackling only the former problem by developing a plasma-chemistry model of uranium molecular species formation during the early stages of nuclear fireball expansion. The model features a newly constructed U$_x$O$_y$ reaction mechanism that consists of 30 reaction channels for 11 uranium molecular …
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Deposition of aluminum oxide by evaporative coating at atmospheric pressure (ECAP)
… and microelectronics. Recently, the Center for Plasma-Material Interaction (CPMI) has developed innovative coating method of Evaporative Coating at Atmospheric Pressure (ECAP). This new idea is an atmospheric-pressure based process. By using the thermal energy of plasma, solid aluminum are …
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Comparative Investigation of LIBS Spectra and Crater Morphology During Laser Ablation of Eutectic BiSn Alloys
… composition between the target material and the plasma plume, and the ablation thresholds for different materials. This dissertation research presents a novel approach for monitoring material transfer during the ablation process of eutectic Bismuth-Tin (BiSn) alloys as the investigated material. …
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Computational modeling of expanded plasma plumes in vacuum and in a tank
… thruster, however, releases a partially ionized plasma plume which contaminates any surface it comes into contact with. Backflow contamination can lead to sputtering and effluent deposition on critical spacecraft components. A computational method for studying these interactions was developed by …
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Effect of electric fields on the synthesis of nanoparticles of tin and silicon in a liquid environment
… beam vaporizes the target material forming a plasma plume which contains ions, electrons, nanoparticles, and nano clusters. High pressures, high temperatures and high energy densities are created in this method. These conditions are favorable for the formation of metastable phases resulting in …
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Field emission of ZnO nano-structures produced by laser ablation
… to investigate the properties of laser produced plasmas, with in-situ time of flight mass spectrometry, for deposition of ZnO materials for applications as field electron emission sources. The results from the work are concerned with the study of the important physical processes present in a …
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Computational and experimental analysis of HIIPER MPD propulsion system
Helicon Injected Inertial Plasma Electrostatic Rocket (HIIPER) is a deep space electric propulsion system developed on the principles of inertial electrostatic confinement (IEC) fusion and helicon plasma injection. It is a stepping stone towards a variable impulse pulsed fusion rocket. HIIPER …
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Operation Mode Transitions in a Heaterless Hollow Cathode
… presence of high-energy ions generated in the plasma plume. These ions impact the cathode's keeper electrode destroying it over a period of tens of thousands of hours. The increased interest in high-power electric propulsion systems has been motivated by proposed missions with long required …
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Physics and application of an atmospheric pressure plasma jet
Non-thermal atmospheric pressure plasma jets are a promising new field of research which are beneficial to many associated technologies, such as material treatment and biomedical applications. The interest in this type of plasma lies in their ability to deliver significant densities of reactive …
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Graphene Oxide Reinforcement in Plasma Sprayed Nickel-5%Aluminum Coatings
<p>Metallic plasma sprayed coatings are widely used in the aerospace industry for repair on worn engine components. However, the inherent defects in these coatings limit the variety of repairs and reduce the service life of the repaired parts. A potential solution to overcome this problem is to mix …
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A Homegrown DSMC-PIC Model for Electric Propulsion
… electric propulsion engines, particularly of the plasma plume. The Navier-Stokes equations used in classic continuum computational fluid dynamics do not apply to the rarefied plasma, and therefore another method must be used to model the flow. A good solution is to use the DSMC method, which uses …
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Performance characterization and optimization of a diverging cusped field thruster with a calibrated counter-weighted millinewton thrust stand
… The DCFT is a magnetically conned plasma thruster that uses cusped magnetic fields to confine electron ow and reduce losses to the walls. The magnetic confinement of the plasma away from the walls also reduces wall erosion to increase thruster lifetime. Additionally, modifications …
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Development of planar langmuir probes for supersonic plasma flows
… for the investigation and char- acterization of plasmas. Diagnostic use of planar Langmuir probes in sta- tionary low temperature plasmas is a well understood and long established technique. When the plasma possesses a drift velocity greater than the ion sound speed the flow is considered to be …
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DIAGNOSTICS AND REAL-TIME MONITORING OF PULSED LASER ABLATION
… materials and multi-layer structures. Plasma emission spectrum and its dynamics are also analyzed during pulsed laser deposition of Ti thin film and laser deflash of molding compounds for integrated circuit (IC) packaging. To correlate with thin film quality, plasma plume is imaged by …
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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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Ultra-thin boron nitride films by pulsed laser deposition: Plasma diagnostics, synthesis, and device transport
… The use of optical emission spectroscopy during plasma growth provides insight into chemistry, kinetic energies, time of flight data, and spatial distributions within a PVD plasma plume ablated from a boron nitride (BN) target by a KrF laser at different pressures of nitrogen gas. Time resolved …
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CHAOS: A multi-GPU PIC-DSMC solver for modeling gas and plasma flows
Numerical modeling of gas and plasma-surface interactions is critical to understanding the complex kinetic processes that dominate the extreme environments of planetary entry and in-space propulsion. However, simulations of these systems that evolve over multiple length- and time-scales is …