What matters more for maneuverability, thruster grade, or weight. Direct thrust measurements of a permanent magnet helicon double layer thruster have been made using a pendulum thrust balance and a high sensitivity laser displacement sensor. It was created by australian scientist dr christine charles, based on a technology invented by professor rod boswell. The helicon source is a device capable of highefficiency plasma generation. The results show a high energy ions flux at almost two times the ion sound speed. Helicon double layer thruster breakthrough in 2003, researchers at the australian national university in canberra created a plasma double layer in the laboratory. Helicon double layer thruster concept for high power nep missions. The helicon double layer thruster hdlt is being developed in the space plasma, power and propulsion group led by professor christine charles at the research school of physics at the australian national university in canberra, australia. If chemical propulsion is capable of great thrust on the order of several mega newtons it also has very low specific impulse a measure of the propellant burn rate. Overview of advanced electromagnetic propulsion development. The potential jump is larger than the experimental measurements and, sometimes, lower. Direct thrust measurements of a permanent magnet helicon double layer thruster have been made using a pendulum thrust balance and a high. Numerical simulations of the helicon double layer thruster concept final report contractor cisas g.
Given the cylindrical symmetry of the problem, the particle orbits are generated. As time progresses, more plasma thrusters are likely to see flight time on objects that leave earths surface. High efficiency operation of a highthrust, low specific impulse hall thruster for inspace propulsion. A high specific impulse twostage hall thruster with plasma. These measurements are used in conjunction with previous characterization of the helicon plasma to create a model of the discharge plasma within the gridded thruster. Ion and hall thrusters march 2008 the research described in this publication was carried out at the jet propulsion laboratory, california institute of technology, under a contract with the national aeronautics and space administration. In this thruster design, gas is injected into a tubular chamber the source tube with one open end. Development of a helicon thruster requires a performance baseline as a basis. Performance degradation mechanism of a helicon plasma thruster. Since then, helicons found use in a variety of scientific and industrial applications wherever highly efficient plasma generation was required, as in nuclear fusion reactors and in space propulsion where the helicon double layer thruster and the variable specific impulse magnetoplasma rocket both make use of helicons in their plasma. A high specific impulse means that the gases shooting out of the back of the rocket are moving at a very high speed but the low thrust means that there is not a lot of gas moving at any one time.
The highest achievable maneuverability without engineering is achieved when your ship is at or bellow half the optimal mass stat, this is also referred to as the minimum mass stat in. In its lowest impulse range, the s4 demonstrated up to twice the efficiency of a s10 thruster for a 15 mns impulse. High efficiency operation of a highthrust, lowspecific impulse hall thruster for inspace propulsion. Proposed here is a full performance characterization of the x3 nestedchannel hall thruster nht, a 100kw class thruster developed jointly by the plasmadynamics and electric propulsion laboratory pepl at the university of michigan, nasa, and the air force office of scientific research. It creates thrust by accelerating ions using electricity an ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. Possible breakthroughs to over 250,000 specific impulse. Efficiency analysis of a highspecific impulse hall thruster. The superconducting helicon thruster presents the possibility for developing higher specific impulse at much greater efficiency, comparable to that of existing stateoftheare hall thrusters.
As a result, the specific impulse of an electric propulsion system will be determined. These systems are an order of magnitude more efficient than chemical propulsion systems, with a specific impulse isp from 2,0003,000 seconds compared to 200500 seconds. Helicon double layer thruster concept for very high power nep. The ion production cost of a helicon plasma source is determined using a gridded ion thruster con. Ion voltage diagnostics in the farfield plume of a high. Download citation add to favorites reprints and permissions. A part of the performance degradation mechanism of the advanced, electrodeless, helicon plasma thruster with a magnetic nozzle, has been revealed by. This new propulsion concept has the potential to propel humans to mars and beyond and greatly decrease the costs of maintaining satellites and spacecraft in their desired orbits. Like most ion propulsion devices, the hdlt is a low thrust, high specific impulse isp thruster. Helicon double layer thruster sp3 has invented the worlds first helicon double layer thruster hdlt. Once in orbit and free of the atmosphere, specific impulse becomes more important, though thrust will still be a factor. Hiiper allows for improved variable specific impulses and high thrust to power ratio by decoupling the ionization helicon and acceleration iec stages of the plasma thruster.
Compute the thruster specific impulse and thrust with a given plasma source. A mediumpower helicon thruster mpht is an electric propulsion device that uses a helicon plasma source to achieve specific impulses of up to 1500 s with argon propellant. Helicon double layer thruster concept for high power. With a specific impulse isp in excess of 2500 seconds, no moving parts and unpressurized tanks containing zerovapor pressure liquid propellant, they can be integrated into cubesat compatible multithruster assemblies. Specific impulse by examining a range of thruster sizes and operating conditions,9,10 11 we are able to make modeling predictions.
There are many factors that determine the grid design in ion thrusters. A helicon double layer thruster hdlt is a type of plasma thruster, which ejects high velocity ionized gas to provide thrust to a spacecraft. These new and improved tools include a novel 2d code of the plasmawave interaction, and. Wilhite langley professor of the practice school of aerospace engineering georgia institute of technology dr.
A reversedfield energy analyzer past the double layer showed two peaks, one at the local space potential and the other 16v beyond that, indicative of an ion beam with vex 8. A helicon doublelayer thruster hdlt is a type of plasma thruster, which ejects high velocity ionized gas to provide thrust to a spacecraft. Design and experiment have established that hall thrusters can operate efficiently at highspecific impulse. Numerical simulation of the helicon double layer thruster concept. The helicon double layer thruster is a prototype spacecraft propulsion engine. Direct thrust measurement of a permanent magnet helicon. Perspectives, frontiers, and new horizons for plasmabased space. Reference herein to any specific commercial product, process, or service. The grids must extract the ions from the discharge plasma and focus them through the. Design and experiment have established that hall thrusters can operate efficiently at high specific impulse.
Dr christine charles has invented the worlds first helicon double layer thruster or hdlt. This concept was named the helicon double layer thruster hdlt. Electric propulsion engines of the types youre interested in, however, make an extreme tradeoff of minimal thrust in favor of very high specific impulse. Xenon ion beam characterization in a helicon double layer. Specific impulse and efficiency range from 16003400 seconds and 5161%. The s43 em1 design demonstrated a very effective and steady behaviour over a wide inlet pressure range, for both, steady state and pulse mode firing. A cylindrical hall thruster cht is a type of hall thruster designed for low power operations. However, a need still exists to better understand the relationship between the thruster design and the plasma. One of the most important parameters for this study is the curve of thruster power in terms of the specific impulse i sp. How is helicon double layer thruster physics abbreviated. Walker, advisor associate professor school of aerospace engineering georgia institute of technology dr. Performance characterization of a helicon double layer thruster. Helicon double layer thruster concept for high power nep. Electrostatic thruster performance u e specific impulse find exhaust velocity from energy balance per particle so maximum ideal specific impulse limited by voltage difference across accelerator e exit inlet v v m q u 2 s m mw v accel volts,890 for singly ionized mu2 q v 2 1 u e o e sp g u i 1amu 1.
A twostage hall thruster with a helicon preionization stage has been. Using water vapor allows for insitu resource utilization, since water is thought to be ubiquitous throughout the solar system. Hdlt stands for helicon double layer thruster physics. Performance goals include thruster efficiencies on the order of 40% to 54% over a specific impulse range of 2000. Hdlt helicon double layer thruster physics acronymfinder. It was created by australian scientist dr christine charles, based on a technology invented by professor rod boswell, both of the australian national university. The ds1 ion propulsion engine only produces 92 mn milli newtons of thrust which is roughly equivalent to the weight of a couple drops of water. Figure 1 photograph of the p52, a high specific impulse twostage hall thruster with plasma lens focusing. Ion energy distribution functions indicate that increasing. Highspecificimpulse electrostatic thruster with argon propellant. Sep systems are also very resilient and, if refueled, could provide a. The helicon double layer thruster hdlt concept is based on the recent discovery of a currentfree electric double layer dl in a helicon plasma expanding in a diverging magnetic field. Direct thrust measurement of a permanent magnet helicon double.
For the initial ascent from earth into space, thrust is most important. May, 2015 a part of the performance degradation mechanism of the advanced, electrodeless, helicon plasma thruster with a magnetic nozzle, has been revealed by the research group of dr. Nasa development of a superconducting helicon thruster. The propulsion community usually uses two quantities to qualify a thruster, the thrust t. Jan 22, 2016 the helicon double layer thruster is a prototype spacecraft propulsion engine. While vasimr uses decoupling with icrh antenna heating, the iec heating section allows unmatchable ion energies, power scaling and efficiency, with the added advantage. Electrostatic thruster performance u e specific impulse find exhaust velocity from energy balance per particle so maximum ideal specific impulse limited by voltage difference across accelerator e exit inlet v v m q u 2 s m mw v accel volts,890 for singly ionized mu2 q. Ion production cost of a gridded helicon ion thruster. As specific impulse increases, the discharge voltage will increase as well. Effect of source diameter on helicon plasma thruster.
Performance analysis of a mediumpower helicon thruster. Characterization of a 100kw three channel nested hall thruster. Helicon double layer thruster concept for high power nep missions prepared by roger walker, advanced concepts team 4month ariadna study 25keuro background. Both the experiment and theory show that the operating range of. Jeanluc raimbault helicon double layer thruster concept for high po wer nep. This study is devoted to simulating the orbits of the ions in the supersonic beam observed experimentally in the laboratory development of the helicon doublelayer thruster. New advances on the simulation of the helicon plasma discharge are also detailed. The design has been verified by the esa, which is participating in its development. Think of thruster grade as how well the thrusters can move x mass so once youve got the maximum thruster grade then mass is the determinant factor. The helicon doublelayer thruster is a prototype spacecraft propulsion engine. Unlike conventional annular hall thrusters, the cht has a smaller surfacetovolume ratio that makes it more convenient for miniaturization and ensures reduced plasmawall interactions, leading to erosion of the thruster channel. A specific impulse of 3800 s with thrust efficiency greater than 30% was obtained. Helicon double layer thruster concept for very high power. The thruster reached a specific impulse of up to 298 s at 4.
Thrust measurements of a radio frequency plasma source. Could nasa use ion propulsion to put a ship into space. Both the experiment and theory show that the operating range of the hdlt in xenon extends to lower pressure than for argon. Deepspace or near earth planets nep explorations require large. Low thrust, low impulse bit reaction control thruster esas. An ion thruster or ion drive is a form of electric propulsion used for spacecraft propulsion. Since then, the company has launched another hall effect thruster in 2011. Helicon double layer thruster applications cpf anu. A maximum effective specific impulse of 280 s was determined using the thrust data. A currentfree electric double layer is created in a helicon double layer thruster operating with xenon and compared to a recently developed theory. Figure 2 shows the total specific impulse and total efficiency of the nasa173mv2 at 10 mgs versus discharge voltage.
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