Abstract
The signatures of turbulence in atmospheric laser propagation are examined, with a particular focus on the effects of non-Kolmogorov turbulence on laser scintillation and phase fluctuations. Non-Kolmogorov properties of the atmospheric index-of-refraction spectrum are outlined, and it is shown that it may be possible to reproduce these features through broadband power-law forcing of the velocity and temperature fields in turbulent flows. Numerical simulations of homogeneous isotropic turbulence subjected to power-law forcing are used to motivate a spectral model for the kinetic energy, which is then extended to address power-law forcing of passive scalars such as the temperature. A modeled non-Kolmogorov index-of-refraction spectrum for power-law forced turbulence is proposed, where the model spectrum consists of standard Kolmogorov and forcing-dominated contributions. This form could reproduce the experimentally observed signatures of atmospheric turbulence on laser propagation and it may provide insights into the origins of non-Kolmogorov turbulence in the atmosphere.
Peter Hamlington
Associate Professor
Peter is an associate professor in the Paul M. Rady Department of Mechanical Engineering at the University of Colorado Boulder and the principal investigator of the Turbulence and Energy Systems Laboratory.