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Showing 1 to 20 of 21 for “"Helicon plasma"”.
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Resonant ion heating in a helicon plasma
… controlling the ion temperature anisotropy in a helicon plasma source. The system uses two rectangular coils placed on either side of the cylindrical pyrex vacuum chamber to create a time dependent magnetic field transverse to the steady state axial field. A 1 kW, 25--125 kHz RF generator powers …
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Propulsion mechanisms in a helicon plasma thruster
… of a compact electric thruster utilizing a helicon plasma source is investigated with the goal of identifying potential thrust mechanisms. Performance characteristics such as thrust, specific impulse, ion cost and thrust efficiency are discussed and related to plasma parameters. The design …
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Analysis of power balance in a helicon plasma source
This thesis analyses the Helicon Injected Inertial Plasma Electrostatic Rocket (HIIPER), a space propulsion concept consisting of a helicon source for plasma generation and an ion extraction method using a nested pair of inertial electrostatic confinement (IEC) grids that are asymmetrically …
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Development and Characterization of Conventional and Inverted Helicon Plasma Sources
Made available in DSpace on 2017-07-06T18:55:19Z (GMT). No. of bitstreams: 3 Masters_Benjamin_C_MS.pdf: 18600523 bytes, checksum: 3032067e89a45e39cfe4a8170385b677 (MD5) Masters_Benjamin_C_MS_ABS.pdf: 52155 bytes, checksum: 4de6d980b5c087fa233baf754ce1dc2b (MD5) license.txt: 4813 bytes, checksum: …
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Power balance in a helicon plasma source for space propulsion
… power balance of an electric thruster based on a helicon plasma source is presented. The power balance is shown to be comprised of several variables, including the RF power supplied to the system, dissipative losses in transmission hardware, losses in the neutral confinement tube, uncoupled RF …
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Empirical aspects of a Mini-Helicon Plasma Thruster Experiment (mHTX@MIT)
A helicon plasma source experiment has been developed and then constructed in the MIT Space Propulsion Laboratory (SPL) vacuum chamber. This experiment allows study of the intrinsic advantages of efficient helicon plasma production for use in space electric propulsion. Historical helicon experiment …
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Dynamics of Turbulence and Flows in a Helicon Plasma Under Electrode Biasing
… sheared flow were carried out using the linear Helicon-Cathode (HelCat) device. Without any outside influence, such as biasing or momentum input, fluctuations were observed. The dynamics of these fluctuations was found to vary with magnetic field, varying in both frequency and mode number. At …
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Optimization of a helicon plasma source for maximum density with minimal ion heating
… and perpendicular ion temperatures in an argon helicon plasma are presented for five different antennas: A Nagoya type III antenna, a double-saddle antenna, a 19 cm long m = +1 helical antenna, a 30 cm long m = +1 helical antenna and a 19 cm m = +1 helical antenna with wide straps. …
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An analysis of energy balance in a helicon plasma source for space propulsion
This thesis covers work done on the mHTX@MIT helicon source as it relates to the analysis of power losses. A helicon plasma is a rather complex system with many potential loss mechanisms. Among the most dominant are optical radiation emission, wall losses due to poor magnetic confinement, and poor …
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Formation and extraction of a dense plasma jet from a helicon-plasma-injected inertial electrostatic confinement device
… modes of operation for the confinement of plasma. Although the symmetric grid star-mode is the most often studied for its application to fusion, the asymmetric grid jet-mode has its own potential application for electric space propulsion. The jet-mode gets its name from the characteristic …
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Three Dimensional Imaging of Helicon Wave Fields via Magnetic Induction Probes
… provide fundamental insight into laboratory helicon plasma. The methods and results derived here will supplement and aid the design of future helicon plasma sources.
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Development and characterization of an inertial electrostatic confinement thruster
… measurements were obtained. As an addition, helicon plasma injection into the IEC was studied, and based on findings suitable recommendations for the development of the helicon-injected IEC thruster were proposed.
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Physics of RF heating systems on proto-MPEX
… of the main challenges being the development of Plasma Facing Components (PFC) that can survive the extreme environment encountered in a fusion reactor. To expedite the testing and development of PFCs Oak Ridge National Laboratory (ORNL) is building the Materials Plasma Exposure eXperiment …
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Emission spectroscopy for the study of electric propulsion plasmas
… rely on the acceleration of highly ionized plasmas to produce thrust at specific impulses unattainable with state-of-the-art chemical systems. This thesis examines the use of a miniaturized Helicon plasma source for an open-ended, electrode-less, cathode-less thruster through emission …
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Additively Manufactured, Multi-Langmuir Probe Plasma Sensing Device for Use on CubeSats
… probe (LP) sensor array for CubeSat ionospheric plasma diagnostics. The ionosphere is a critical layer of Earth's atmosphere consisting entirely of plasma, and reliable in-situ measurements made on satellites orbiting within the ionosphere are necessary for better understanding its properties. …
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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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Analysis of energy balance in a helicon coupled to an inertial electrostatic confinement device
The characteristics of the helicon plasma injection into the IEC were explored. The first such analysis was a COMSOL simulation to determine the voltage as a function of position in the helicon dielectric tube when the IEC cathode is biased to several kilovolts. This COMSOL simulation contained no …
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Real-time RBS analysis of plasma erosion in DIONISOS
… commercial nuclear fusion reactors lies at the plasma-material boundary. Plasma temperatures greater than 10 million degrees Celsius (10 keV) require clever magnetic field configurations to confine the plasma near the center of the toroid. However, the materials directly surrounding the plasma, …
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Theoretical studies of the VASIMR plasma propulsion concept
… by the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) project. The VASIMR device has a magnetic mirror configuration and consists of three main components: a low energy helicon plasma source, which creates cold plasma via rf-discharge; an ion cyclotron-resonance heating (ICRH) …
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Enhancing retarding potential analyzer energy measurements with micro-aligned electrodes
Plasmas are ionized gases, and constitute a large fraction of the known universe. For example, solar wind is a plasma that emanates from the sun reaching the Earth's magnetosphere. At times these ionized species cause beautiful auroral displays over the planet's magnetic poles. Moreover, when a …
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