Accession Number : ADA261429

Title :   Chaos Metrics for Testing Lagrangian Particle Models.

Descriptive Note : Technical rept. Mar-Dec 92,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF PHYSICS

Personal Author(s) : Kamada, R. F.

Report Date : 31 JAN 1993

Pagination or Media Count : 113

Abstract : The Lorenz and Henon attractors and two atmospheric Lagrangian particle models were tested using self-affine fractal dimension, DA, Shannon information entropy, S, and the Lyapunov exponent, lambda, along with turbulent kinetic energy, vertical variance, and Brunt-Vaisala Frequency. Results show that (1) chaos metrics are a new set of tools to assess the micro behavior of Lagrangian particle models, (2) that periodicity in bifurcatory systems differs from wave behavior in fluids, since wave states are not limited to amplitude extrema. (3) Non-spectral particle models lead to unrealistic variations in 'the chaos metrics with changes in buoyant stability. (4) S and DA behave oppositely at times, implying that diffusion and dispersion are not equivalent, even in the absence of mean windflow.... atmospheric dispersion/diffusion, Lagrangian particle models chaos, Self-affine fractals, Turbulence, Atmospheric boundary layer, strange attractors, Monte Carlo models, Lyapunov.

Descriptors :   *CHAOS, *PARTICLES, *TURBULENT DIFFUSION, *COMPUTERIZED SIMULATION, *ATMOSPHERIC DISTURBANCES, *METRIC SYSTEM, AMPLITUDE, ATMOSPHERICS, BOUNDARIES, BOUNDARY LAYER, DIFFUSION, DISPERSIONS, ENERGY, ENTROPY, FLUIDS, FRACTALS, FREQUENCY, KINETIC ENERGY, KINETICS, LAYERS, MEAN, PERIODIC VARIATIONS, STABILITY, VARIATIONS, ATMOSPHERE MODELS, LYAPUNOV FUNCTIONS, WEATHER FORECASTING, TEST AND EVALUATION.

Subject Categories : Meteorology
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE