Thermal blooming with laser-induced convection: radial basis function simulation

Abstract

The propagation of a high energy laser through a nearly stagnant absorbing medium is studied. The absorption values and time scale of the problem are such that the laser induces convective heat currents transverse to the beam. These currents couple to the laser via the refractive index, causing time dependent thermal blooming. A numerical method is developed and applied to the model in [J. Electromagn. Waves Appl. 33, 96 (2019)JEWAE50920-507110.1080/09205071.2018.1528183], using radial basis functions for spatial differencing, which allows for irregular point spacings and a wide class of geometries. Both the beam and laser-induced fluid dynamics are numerically simulated. These simulations are compared to a historical experiment of a 300 W laser in a smoke-filled chamber with good agreement; both cases include a crescent shaped spot at the target.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 22, 2023
Source ID
10.1364/ao.487903

Entities

People

  • Benjamin F. Akers
  • Jonah A. Reeger
  • Steven T. Fiorino

Organizations

  • Air Force Institute of Technology
  • Air Force Office of Scientific Research
  • Office of Naval Research

Tags

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Space
  • Space - Hall-Effect Thruster