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Magnetic Field Thruster Developed
ndverdo writes "There are reports of a working magnetic field engine prototype based on Alfvén waves designed by Austrian scientists. According to the reports fuel savings in rocket engines of 90% could be achieved. Other benefits include enhanced durability due to the nozzle forming outside the engine."
Just thinking that it woulda saved me a headache ifn I'd noticed it was a babelfish translation earlier.
rewriting history since 2109
...and it was not "Chinglish"; it is the inevitable byproduct of using a machine without experience or intelligence to translate between two dramatically different languages. Grammatical errors are going to happen.
This sort of thing has been in the works forever and there's entire university physics and astrophysics texts written on it as well as related disciplines including plasma and ion propulsion. That the superheated reaction products of a rocket are ionized and thus subject to magnetic fields is well known. What is not well known is when we might make some use of this.
We do know that various superconductors are in that state when subjected to the cryogenic temperatures of liquified oxygen and hydrogen and using the fuel and oxidizer to cool such magnets would be an interesting thing. It would have to be in the line before the liquified reactants reached the nozzle cooling section but if it worked it might well dramatically reduce the size and thus mass of the nozzle and thus the cooling requirements as well. It depends on the tradeoff of field generating power equipment, coils, and so forth.
Ultimately the basic research being done here will be contributory to the future of space propulsion in its own small way.
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
The basic idea of how this works is like a railgun, except you're trying to get the gun to move, not the projectile. Two parallel bars, with a third across the two, and massive current going through the system. The third bar experiences terrific force. In this system, the perpendicular bar is actually a conducting gas.
To learn German than try and untangle that horrible babelfish translation. The funny part was that I read about 4 paragraphs before realizing it was a Babelfish translation, and the whole time wondered what incompetant wrote it :P
Anyway, here's a better(or at least another) translation done by ImTranslator.
http://webtranslation.paralink.com/webtarget.asp?u rl=http%3A%2F%2Fdiepresse.at%2FArtikel.aspx%3Fchan nel%3Dh%26ressort%3Dws%26id%3D512951%26lp%3Dde_en& dir=de%2Fen&dic=general&auto=
Good explenation of MPD
Further implications of magnetic nozzle control can be found http://www.ess.washington.edu/Space/magbeam/NIAC20 05/NIACmagbeam2005.ppt
They usually have problems with erosion, not to mention the low thrust-to-weight ratio (which means you cannot get off the Earth's surface with one). Also, they take a lot of juice, so you likely need something like a nuclear reactor or friggin huge solar array (we are talking MW here) to generate enough electricity to power one of these babies.
Not being familiar with Alfvén waves, I am not sure how the velocity of the exhaust is increased. Could these waves be forced via magnets to form a constriction in the flow, forcing the vented material through a smaller "exhaust port"? (This would be in keeping with the separation of combustion from the nozzles.)
.. paranoid crackpot leftover from the days of Amiga.
I just wasted 20 minutes of my life. Here is the result:
The idea is 20 years old and was conceived by Manfred Hettmer, president of the austrian mars society. A new plasma-engine based on "Alfven-waves" could increase the thrust of a rocket while at the same time drastically reducing its fuel consumption. At least that is the theory.
And in practice, in tests the plasma-engine achieved fuel savings of around 90%, which is no small thing: "A sattellites weight is 50% fuel, because its fuel determines its life time. Without engines the sattellite could not keep it's exact position", says project coordinator Andreas Grassauer.
The basis of the development is a discovery by nobel prize winning physicist Hannes Alfven in the year 1942. Alfven was researching, among other things, magnetohydrodynamics (MHD), which describes the interaction between an electically conductive fluid with electic and magnetic fields, and also the propagation of waves in the fluid - now known as "Alfven-waves".
Now, for the first time, there is a technical implementation of the "Alfwen-waves", that, in Grassauer's words, "could be the start of a new era in rocket engine technology". The main feature of the technology is a ten times higher escape speed, that can otherwise only be achieved by a fusion engine, which doesn't exist yet. The measurements were taken on a prototype engine in a vacuum chamber. Also, corrosion of the engine is avoided since the thrust is achieved using the magnetic jet on the outside.
Economically, there has been some interest in the project already. Besides Grassauer and Hettmer the experimental physicist Norbery Frischauf, system engineer Tobias Bartusch and Otto Koudelka of the TU Graz are also involved. On the 15th of October the plasma-engine will be shown for the first time at the convention of the Internation Aeronatic Federation (FAI) in Japan.
MOA: Magnetic Field Oscillating Amplified Thruster
Mr. Norbert Frischauf, Booz Allen Hamilton, Austria
Mr. Tobias Bartusch, University of Augsburg, Germany
Dr. Andreas Grassauer, Green Hills Biotechnology, Austria
Mr. Manfred Hettmer, Manfred Hettmer Datenverarbeitung, Austria
Abstract - It was in 1942, when the later Nobel laureate Hannes Alfvén published a letter, stating, that oscillating magnetic fields can accelerate ionised matter via magneto hydrodynamic interactions in a wave like fashion. These waves were later called "Alfvén waves", in honour of their discoverer. Although the evidence for Alfvén's hypothesis came already rather early with the observation of certain plasma phenomena, such as being connected with high solar wind Wolf-Rayet stars, more than 60 years had to pass by before a technical implementation of Alfvén waves for propulsive purposes was proposed for the first time.
The name of the concept, utilising Alfvén waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfvén waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system.
It is this deformation that generates Alfvén waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system.
Based on computer simulations, which we conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power.
Although a dual-use system, space propulsion is expected to be the prime application for MOA. As MOA works best in high-power mode and with ionised matter, utilisation concepts range from a high-efficient Nuclear Electric Propulsion System, to an 'afterburner' for Nuclear Thermal Propulsion Systems. This wide range of applications makes MOA a unique accessory for any nuclear propulsion system to overcome specific concept drawbacks, allowing a full-fledged hybrid nuclear propulsion system, with attune able thrust / specific impulse parameters, perfectly suited for nearly all types of space missions.
This article will be presented on Friday, October 21 2005, 08h30m at the 56th International Astronautical Congress in Fukuoka, Japan.
Pay attention to the URL. It's been babelfish'd from German... Though it would be nice if the summary warned you about that. It threw me for a loop at first too.
These guys have come up with a way to accellerate a plasma with just magnetic fields: no electrodes need be exposed to the plasma.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.