Chaos in thermal pulse combustion.

Chaos

Engineering Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831U.S. Department of Energy, Morgantown Energy Technology Center, Morgantown, West Virginia 26505Embry-Riddle Aeronautical University, Department of Aerospace Engineering, Daytona Beach, Florida 32114.

Published: December 1995

An experimental thermal pulse combustor and a differential equation model of this device are shown to exhibit chaotic behavior under certain conditions. Chaos arises in the model by means of a progression of period-doubling bifurcations that occur when operating parameters such as combustor wall temperature or air/fuel flow are adjusted to push the system toward flameout. Bifurcation sequences have not yet been reproduced experimentally, but similarities are demonstrated between the dynamic features of pressure fluctuations in the model and experiment. Correlation dimension, Kolmogorov entropy, and projections of reconstructed attractors using chaotic time series analysis are demonstrated to be useful in classifying dynamical behavior of the experimental combustor and for comparison of test data to the model results. Ways to improve the model are suggested. (c) 1995 American Institute of Physics.

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http://dx.doi.org/10.1063/1.166137DOI Listing

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