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) [CrossRef]  ], 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.

Numerical simulation of steady-state thermal blooming with natural convection

Jeremiah S. Lane, Justin Cook, Martin Richardson, and Benjamin F. Akers
Appl. Opt. 62(8) 2092-2099 (2023)

High-precision calculation and experiments on the thermal blooming of high-energy lasers

Qi Zhang, Qili Hu, Hongyan Wang, Ming Hu, Xingyu Xu, Jingjing Wu, and Lifa Hu
Opt. Express 31(16) 25900-25914 (2023)

Thermal Blooming of Laser Beams in Fluids

John N. Hayes
Appl. Opt. 11(2) 455-461 (1972)

Mitigation of thermal blooming by rotating laser beams in the atmosphere

Die Qiu, Boyu Tian, He Ting, Zheqiang Zhong, and Bin Zhang
Appl. Opt. 60(27) 8458-8465 (2021)

Laser-induced bubble trapping in liquids and its effect on light thermal blooming

A. Marcano O
Appl. Opt. 31(15) 2757-2764 (1992)