Free-Troposphere

ModelingToolkit implementation of the Free troposphere atmospheric aerosol size distribution, from Seinfeld & Pandis (2006), Atmospheric Chemistry and Physics, 2nd ed., Chapter 8 ("Properties of the Atmospheric Aerosol"), Table 8.3. The Free troposphere distribution is a preset of the multi-modal lognormal AerosolDistribution model: three lognormal modes (N = [129, 59.7, 63.5] cm^-3, D_g = [0.007, 0.250, 0.520] um, log10 sigma = [0.645, 0.253, 0.425]) — a nucleation/ultrafine mode at 7 nm plus two sub-micron accumulation modes. The model represents the aerosol number, surface-area and volume distributions as a sum of the three modes (Eq. 8.54) and reports the total number/surface/volume concentrations, the mode-1 Hatch-Choate diameters, and the vertical aerosol mass profile (Eq. 8.55). Migrated from Aerosol.jl FreeTroposphereAerosol, a preset wrapper around AerosolDistribution(3). Purely algebraic: ten observed outputs, no differential states, an empty equations array. The upstream length-n_modes array parameters are scalarized at n_modes = 3 with the Free troposphere Table 8.3 mode parameters as defaults.