Experimental evidence of chaotic behavior in atmospheric pressure arc discharge

Estimation of dynamic properties of attractors observed in hollow copper electrode atmospheric pressure arc plasma system

“…Phase portraits look neither like random, nor like periodic or quasi-periodic, but exhibit some definite structures in phase space, similar to chaotic systems. Although, various signals in the system are the macroscopic consequence of the same chaotic discharge, corresponding attractors look different [2]. This is because the phase portrait displays information contained in time series and time series for various signals are different due to their different intrinsic dependence in terms of micro-macro transitions.…”

“…In the second case (figure 2b), the orbit looks like a toroid due to the presence of noise, while in the third case (figure 2c), the whole space is covered by data points without showing any structure. It can be noted that the phase portraits of experimental signal [2] are completely different in nature from any of these attractors. Phase portraits look neither like random, nor like periodic or quasi-periodic, but exhibit some definite structures in phase space, similar to chaotic systems.…”

“…Details of system dynamics, typical fluctuating behavior of the signals and structural details of the torch are available elsewhere [1,2]. Three signals representing the dynamic voltage, acoustics and optical outputs are generated from the plasma.…”

“…Three signals representing the dynamic voltage, acoustics and optical outputs are generated from the plasma. Attractors corresponding to different signals from the system have been constructed using standard delay technique [2]. To compare results with periodic, noisy and periodic signals mixed with some percentage of noisy signals, we have considered a periodic signal (figure 1a) and a white noise signal (figure 1b) generated using runtime subroutine RANDOM, available in Microsoft Fortran Version 1.0 (1993).…”

“…Recently, dynamic characteristics of movement of arc root inside a hollow copper electrode plasma torch have been investigated using voltage, optical and acoustic signals generated from the device and evidence for the existence of chaotic regime and possibility of its online control have been reported based on time series, power spectrum, Lyapunov exponent, dimension, attractor structure of experimental signals and system dynamics [1,2]. The logical evolution of the estimation procedure for identification and characterization of chaos in such experimental systems are scarce and are of much value to future workers in this area.…”