Numerical Methods in Aero-optics

Physics and Computation of Aero-Optics

This article provides a critical review of aero-optics with an emphasis on recent developments in computational predictions and the physical mechanisms of flow-induced optical distortions. Following a brief introduction of the fundamental theory and key concepts, computational techniques for aberrating flow fields and optical propagation are discussed along with a brief survey Annu. Rev. Fluid ...

Resolution requirements for aero-optical simulations

Analytical criteria are developed to estimate the error of aero-optical computations due to inadequate spatial resolution of refractive index fields in high Reynolds number flow simulations. The unresolved turbulence structures are assumed to be locally isotropic and at low turbulent Mach number. Based on the Kolmogorov spectrum for the unresolved structures, the computational error of the opti...

The Optical Environment from the Tip Vortices of a Helicopter in Different Flight Regimes

by Christopher O. Porter Aero-optical aberrations associated with turbulent compressible flow fields can seriously degrade the performance of an optical system; the effect of these aberrations increases as the wavelength of the transiting light becomes shorter, and so is particularly strong at visible and near-infrared wavelengths. These aero-optic aberrations originate from both spatialand tem...

Fluid dynamics and aero-optics of turrets

A summary of research efforts for last several years on fluid-dynamics and aero-optics of hemisphereon-cylinder turrets with flat and conformal windows is presented. The topology of flow behind turrets and both steady and unsteady sources of optical distortions are discussed. Scaling laws for levels of optical aberrations are proposed and results of several experimental studies are compared and...

In-flight aero-optics of turrets