Low Power Plasma Propulsion

Plasma PropulsionTechnology in AstronauticsSYMPOSIUM ON PLASMA AND NUCLEAR SYSTEMS, UOIT, Oshawa, December 22, 2016

by Dr. C. A. Barry Stoute, PhDE-Mail: stoute.barry@gmail.com

OutlineWhat Is Plasma Propulsion & Propulsion Terminologies?Electrothermal EnginesElectrostatic EnginesElectromagnetic EnginesFusion Propulsion ResearchWhat Is Canada Doing in This Research?Current ResearchPossible Future Research

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What Is Plasma Propulsion& Propulsion Terminologies

Electrothermal PropulsionFirst, what is a thermal engine?

NASAs Nuclear Engine for Rocket Vehicle Application (NERVA)

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Electrothermal PropulsionTypes of Electrothermal thrusters

Resistojet Thruster

Arcjet Thruster

RF ThrusterResistojets utilize resistors as heating elements for ionization. The process is inefficient because the cold gas passing through the resistor, it cools down.Arcjets are thrusters that the plasma is ionized by a high voltage DC source. The current is minimal; however, the heating is solely dependent on the potential difference.RF Thrusters are sought to be the best option for electrothermal propulsion. The power required to heat the gas is significantly lower than an arcjet and the configuration can be electrodeless. The problem with RFTs are designing and building the RF system as it is difficult and expensive to build.

Electrostatic PropulsionIon and Hall ThrustersThe principles of electrostatics is the basis of electrostatic propulsion: electric and fields accelerates the ions at hypersonic velocities in small quantities. These engines have one of the highest specific impulse among the plasma thrusters.There are two primary types of electrostatic thrusters: Ion and Hall. These will be discussed in detail in the next slide.Ion and Hall thrusters are commercially available and have been implemented in the aerospace industry. These thrusters are design for deep space missions, such as NASAs NSTAR and Snecmas PPT-1350NASAs NSTAR Ion Thruster: This was the propulsion system for the Deep Space 1 satellite to do a flyby of asteroid 9969 Braille

Snecmas PPT-1350 Hall Thruster: This was the propulsion system for the SMART-1 satellite to do scientific observation of the moon

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Electrostatic PropulsionTypes of Electrostatic thrustersIon ThrusterHall Thruster

Electromagnetic PropulsionIntroductionAd Astras VX-200 VASIMR (Variable Specific Impulse Magnetorocket) in operation.

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Electromagnetic PropulsionTypes of Electromagnetic thrustersPulse Plasma ThrusterVASIMRPulse Plasma Thrusters, or PPTs, uses solid fuel, namely Teflon, as a propellant. A spark plug ablates and ionizes layers of the fuel, and a high current accelerates the plasma.Magnetoplasmadynamic, or MPD, thrusters are the purest form of electromagnetic propulsion. Incoming gas enters the thruster, and high voltage and current occur between the nozzle and the tip. The gas is ionized and accelerated.The variable specific impulse magnetorocket (VASIMR) is a hybrid of electromagnetic and electrothermal propulsion. The gas is heated and ionized by high power RF supply. The plasma is controlled by magnetic fields to prevent the particles touching the walls (similar to MCP), and the plasma is accelerated by an external magnetic field.

MPD Thruster

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Fusion Propulsion ResearchFusion propulsion is currently being researched at many institutions around the world: United States and Europe. The use of fusion propulsion will revolutionize space travel. The time it would take to travel to Mars, for example, reduces significantly.University of Washingtons Electromagnetically Driven Fusion Propulsion

University of Alabama Huntsvilles Z-Pinch Fusion Propulsion

Los Alamos National Laboratorys Magnetized Target Fusion Propulsion

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What Is Canada Doing in This Research?Current ResearchCurrently, there is research on miniaturization of electrostatic and electromagnetic propulsion systems for nanosatellites. Undergraduate students from University of Waterloo and York University have developed electric thrusters for their senior year project. PhD graduate Barry Stoute from York University has developed a hybrid electric thruster design for nanosatellites. A paper has been published on the design of low-cost ion thruster at Canadian Aeronautics and Space Journal in September 2015. Otherwise, the basis of plasma propulsion is used on material and fusion engineering. Universities such as McMaster University work on plasma etching for MEMS development. University of Saskatchewan, UOIT, and CNL are currently doing research in fusion power.

Hybrid Electric Thruster: Parallel combination of electrostatic and electromagnetic propulsion systems for nanosatellites developed from York UniversitySTOR-M Tokamak currently located at the University of Saskatchewan

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What Is Canada Doing in This Research?Current Research Electrothermal Thruster Test In Action

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What Is Canada Doing in This Research?Possible Future ResearchCanada can be the leader of plasma propulsion by concentrating on small satellites.The industry of miniature, micro, nano, and picosatellites are growing exponentially due to their low cost and light weight. Canada can lead the charge by developing miniature ion thrusters. What is required to lead the charge?Plasma Physicists to research the behaviors of charged particles benefiting for propulsionEngineering Physicists to create miniature thrusters by using MEMSChemical and Material Engineers to develop new fuels for the thrustersMechanical and Electrical Engineers for development of the thruster

George Washington Universitys miniature plasma thrustersNanosatellites at University of Toronto

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Some of Non-Astronautical Applications of Plasma Propulsion TechnologyThere are some non-astronautical applications that are derived from plasma propulsion technology.Plasma gasification is one of many applications in which arcjet or RF thrusters are used to incinerate waste. The waste is converted to a synthetic gas where it is used in the Rankine Cycle.Another application is to use electrostatic thrusters as ion sources for surface engineering and thin films. Hollow cathodes and Hall Effect ion sources are used in this particular industry.In fusion energy, ion thruster technology is used for neutral beam injection for the tokamak at ITER. This is an efficient source of plasma heating for fusion.

Thermal Plasma for Gasification from WestinghouseNeutral Beam Injector from the Tokamak at ITER Image from Max-Planck-Gesellschaft

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Thank you for your attentionQuestions?Dr. C. A. Barry Stoute, PhDE-Mail: stoute.barry@gmail.com