MOA: Magnetic Field Oscillating Amplified Thruster
- Paper ID
2095
- author
- company
QASAR Technologie(s) GmbH;
- country
Austria
- year
2005
- 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 were 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. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an ‘afterburner system’ for Nuclear Thermal Propulsion, other terrestrial applications, such as a ‘submarine caterpillar’ or a plasma ejector can be thought of as well, making the system highly suited for a dual-use research and utilisation strategy.