Numerical simulation of steady-state thermal blooming with natural convection
Abstract
This work investigates steady-state thermal blooming of a high-energy laser in the presence of laser-driven convection. While thermal blooming has historically been simulated with prescribed fluid velocities, the model introduced here solves for the fluid dynamics along the propagation path using a Boussinesq approximation to the incompressible Navier–Stokes equations. The resultant temperature fluctuations were coupled to refractive index fluctuations, and the beam propagation was modeled using the paraxial wave equation. Fixed-point methods were used to solve the fluid equations as well as to couple the beam propagation to the steady-state flow. The simulated results are discussed relative to recent experimental thermal blooming results [Opt. Laser Technol.146,107568(2022)OLTCAS0030-399210.1016/j.optlastec.2021.107568], with half-moon irradiance patterns matching for a laser wavelength at moderate absorption. Higher energy lasers were simulated within an atmospheric transmission window, with the laser irradiance exhibiting crescent profiles.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 07, 2023
- Source ID
- 10.1364/ao.484224
Entities
People
- Benjamin F. Akers
- Jeremiah S. Lane
- Justin Cook
- Martin Richardson
Organizations
- Air Force Institute of Technology
- Air Force Office of Scientific Research
- University of Central Florida