Linear theory of uncompensated thermal blooming in turbulence

Journal Article · Fri Jun 15 04:00:00 EDT 1990 · Physical Review, A (General Physics); (USA)

DOI:https://doi.org/10.1103/PhysRevA.41.6982· OSTI ID:6696802

Chambers, D H; Karr, T J; Morris, J R; Cramer, P; Viecelli, J A ^[1]; Gautesen, A K ^[2]

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1. Lawrence Livermore National Laboratory, P.O. Box 808, L-495, Livermore, California 94550 (USA)
2. Department of Mathematics, Iowa State University, Ames, IA (USA)

A linearized theory of small perturbations in thermal blooming gives a surprisingly accurate description of the initial evolution of a plane wave propagating through an absorbing fluid medium. In the case of constant absorption and fluid velocity, a sinusoidal perturbation of the optical field grows quasiexponentially at a rate determined by its Fresnel number and the accumulated optical-path difference due to blooming. Perturbations with small transverse length scales grow more rapidly than those with large length scales. The evolution of the optical field and spectrum in the presence of optical turbulence is accurately described. The growth of the small-scale fluctuations eventually leads to a decrease in plane-wave amplitude. This growth puts an ultimate limit on the amount of power that can be propagated through a turbulent medium such as the atmosphere. More complicated cases with varying absorption and velocity profiles can be analyzed using a WKB approximation. Numerical simulations show growth suppression when the velocity varies along the optical path. These predictions from the linearized theory agree well with results from numerical simulations of the full nonlinear system and thus provides a standard for comparing different numerical codes.

• OSTI ID: 6696802
• Journal Information: Physical Review, A (General Physics); (USA), Journal Name: Physical Review, A (General Physics); (USA) Vol. 41:12; ISSN PLRAA; ISSN 0556-2791
• Country of Publication: United States
• Language: English

Related Subjects

640410* -- Fluid Physics-- General Fluid Dynamics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DISTURBANCES
FLUIDS
NONLINEAR OPTICS
NUMERICAL SOLUTION
OPTICS
TURBULENCE
WAVE PROPAGATION
WKB APPROXIMATION