Propagation of high energy lasers through clouds: modeling and simulation

Area of Science:

• Physics
• Optical Engineering
• Atmospheric Science

Background:

• High energy lasers interact with atmospheric aerosols like water droplet clouds.
• Understanding laser-cloud interactions is vital for applications such as laser communications and remote sensing.
• Previous models often simplified droplet dynamics or neglected feedback mechanisms.

Purpose of the Study:

• To develop a comprehensive model for 10.6 µm high energy laser beam interaction with water droplet clouds.
• To incorporate droplet and vapor heating, and droplet shattering in the "fast regime".
• To investigate the feedback of cloud dynamics on laser propagation through changes in the complex refractive index.

Main Methods:

• Developed a physical model for laser-droplet cloud interaction.
• Included droplet and vapor heating and droplet shattering physics.
• Solved the model exactly in one spatial dimension and performed axisymmetric 3D numerical simulations.

Main Results:

• An explicit formula for the cleared channel front was derived.
• Numerical simulations demonstrated the evolution of the cleared channel.
• The complex refractive index feedback mechanism was incorporated.

Conclusions:

• The developed model provides a more accurate representation of laser-cloud interactions.
• Model predictions offer insights into the limitations and capabilities of high energy lasers in aerosol environments.
• Further research can refine the model for complex aerosol conditions.