Aerosol3D 0.2.0

3D aerosol particle modeling and optical property computation

Aerosol3D

Aerosol3D is a Python toolkit for modeling the 3D geometry and optical properties of atmospheric aerosol particles. It provides a unified pipeline from geometric construction to Discrete Dipole Approximation (DDA) optical computation.

Features

• 3D Geometry Modeling — Build spheres, ellipsoids, cubes, and import fractal aggregates
• Coating Algorithms — Apply distance-based, potential-based, CCM (Closed-Cell Model), and CAM (Coated-Aggregate Model) coatings
• Optical Computation — Solve optical properties via DDA using a Julia-based backend with optional GPU acceleration
• Visualization — Generate 3D screenshots and rotation videos using PyVista
• Material Database — Built-in refractive index data for common aerosol materials
• Flexible I/O — Export to VTP and voxel formats

Installation

Requires Python >= 3.10.

pip install Aerosol3D

For development:

git clone https://github.com/openEarthModelling/Aerosol3D.git
cd Aerosol3D
pip install -e ".[dev]"

Optional Dependencies

• Julia backend (required for DDA optical computation): Install Julia and run pip install pyjulia
• GPU acceleration: Requires CUDA-capable GPU and Julia CUDA packages

Quick Start

from Aerosol3D import (
    AerosolParticle, create_sphere, MixingState,
    preset_material, save_screenshot, solve_optics, SimulationConfig
)

# Create a black carbon sphere
soot = preset_material("black_carbon")
particle = AerosolParticle(
    name="bc_sphere",
    mixing_state=MixingState.INTERNAL,
    unit="nm",
)
particle.add_mesh("core", create_sphere((0, 0, 0), 50.0), soot)

# 3D visualization
save_screenshot(particle, "sphere.png", colors={"core": "black"})

# DDA optical computation
config = SimulationConfig(wavelength=550.0, source="solar")
result = solve_optics(particle, config)
print(f"Extinction efficiency: {result.qext}")

See the examples/ directory for complete workflows including fractal aggregates and coated particles.

Examples

Example	Description
black_carbon_sphere.py	Bare BC sphere with DDA optics
black_carbon_fractal.py	Fractal aggregate via pyFracAggregate with full pipeline

API Overview

Core Classes

• AerosolParticle — Particle container with multiple meshes/materials
• MixingState — Internal / external mixing state
• Material — Refractive index and density
• FractalAggregate — Fractal aggregate geometry

Geometry

• create_sphere(center, radius)
• create_ellipsoid(center, radii)
• create_cube(center, size)

Coating

• apply_distance_coating(particle, thickness, material)
• apply_potential_coating(particle, thickness, material)
• apply_ccm_coating(particle, thickness, material)
• apply_cam_coating(particle, thickness, material)

Optics

• solve_optics(particle, config) — DDA optical solver
• SimulationConfig(wavelength, source) — Simulation parameters

I/O & Visualization

• save_screenshot(particle, path)
• save_rotation_video(particle, path)
• save_vtp(particle, path) / save_voxel(particle, path)

Development

# Run tests
pytest

# Run tests with coverage
pytest --cov=Aerosol3D --cov-report=term-missing

License

MIT License. See LICENSE for details.

Acknowledgments

DDA optical computation is powered by CEMD.jl via a Python-Julia bridge.