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<b>Variational Principle for Optimal Accelerated Neutralized Flow</b>
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Authors: A. Fruchtman and N. J. Fisch
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<b>Date of PPPL Report:</b> October 2000
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<b>Published in:</b> Physics of Plasmas <B>8</B> (January 2001) 56-58.
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Minimizing the energy deposited in the electron current in neutralized flows, such as in the Hall thruster, is examined. Modifying the electron current along the channel by inserting emitting electrodes, can enhance the efficiency. By employing variational methods, an optimal electron current distribution is found. The efficiency enhancement due to this effect, however, is shown to be small.
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