Accession Number:

AD0613387

Title:

ALTERNATING-CURRENT GENERATION WITH MOVING CONDUCTING FLUIDS,

Descriptive Note:

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS

Personal Author(s):

Report Date:

1961-11-30

Pagination or Media Count:

12.0

Abstract:

A one-dimensional, small-amplitude analysis is presented of alternating-current generation by a stationary electromagnetic circuit coupling to waves in a moving, perfectly conducting fluid. In a uniform applied dc magnetic field the waves in the fluid are either compressional waves if the time-average velocity v is transverse to the dc magnetic field, or Alfven waves if it is along the dc magnetic field. It is shown that, for velocities v greater than the velocity of propagation c of the compressional or Alfven waves, self-excited oscillations may be produced in a resistively loaded coil coupling to the fluid. In a traveling-wave circuit and in a resistively loaded distributed circuit coupling to the fluid, growing waves are found which result from a transformation of the fluid energy into electromagnetic energy. There is a close analogy between these power-generation mechanisms and those employed in microwave electron-beam tubes. The results of two- and three-dimensional analyses are summarized in order to show that the phenomena predicted by the simplified one-dimensional analysis occur in less idealized geometries. Possible applications are briefly discussed with reference to ac power generation by using combustion gases or a flow of a high-temperature plasma. Author

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Distribution Statement:

APPROVED FOR PUBLIC RELEASE