Experimental control of chaos in a periodically driven glow discharge

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:232791

Weltmann, K D; Wilke, C ^[1]; Klinger, T ^[2]

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1. Univ. of Greifswald (Germany)
2. Univ. of Kiel (Germany)

The control of the chaotic state of ionization waves in the positive column of a periodically driven neon glow discharge is achieved by an active feedback technique based on the algorithm suggested by Ott, Grebogy and Yorke and a delayed feedback technique. Unstable periodic orbits (UPOs) of both low and high periodicity could be stabilized by small perturbations of suitable frequency and phase shift or a continuous delayed feedback. Strong theoretical and experimental evidence for control of chaos has been demonstrated for a vast variety of different physical and chemical systems. The problem to control the chaotic state of plasma, however, has attracted only few attention, even if the onset and control of chaos is of greatest importance for the study of a nonstationary or turbulence system. The plasma wave type considered here is the propagating ionization wave in the positive column of a neon glow discharge. They are excited by slight deviations of the electron temperature, which cause large ionization fluctuations giving rise to a nonlinear instability with relatively large amplitude. Different types of striations are known which differ in the product of wavelength {lambda} and electrical fieldstrength E (Novak-constant {theta}={lambda}{sm_bullet}E). An external periodic modulation of the discharge current allows to study the nonlinear dynamics of system, where one frequency is given by the propagating spatial mode of ionization wave and another by the modulation signal. In this contribution we want to compare our application of the two algorithms for controlling chaos mentioned above.

• OSTI ID: 232791
• Report Number(s): CONF-950749--
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ALGORITHMS
CONTROL
GLOW DISCHARGES
NEON
RANDOMNESS