Detailed Microphysical Modeling of the Formation of Organic and Sulfuric Acid Coatings on Aircraft Emitted Soot Particles in the Near Field

Figures & data

TABLE 1 Organic surrogate species selected in this work

C* (μg/m^3)	Surrogate species	Saturation vapor pressure at 300°C, C* (μg/m^3)
10^6	Pentanoic acid (C5H10O2)	1.552 × 10^6
10^6	Naphthalene (C10H8)	1.845 × 10^6
10^4	Anthracene (C14H10)	1.469 × 10^4
10^2	Pyrene (C16H10)	3.226 × 10^2
10^0	Perylene (C20H12)	8.018 × 10^−1
10^−2	Anthanthrene (C22H12)	2.164 × 10^−2

FIG. 1. Modeled molar fraction of organic emissions at the engine exit plane.

FIG. 2. Representative modeling results following plume centerline trajectory up to 1000 m downstream: (a) soot coating composition as a function of downstream distance; (b) size-dependent surface coverage at 1000 m downstream; (c) size-resolved composition of soot coatings at 1000 m downstream; (d) size evolution of coated soot particles; (e) dilution factor as a function of downstream distance.

FIG. 3. Effect of (a) ambient temperature and (b) ambient relative humidity levels on the soot properties at 1000 m downstream of the engine.

FIG. 4. Effect of initial organic concentration in the vapor phase on the soot properties at 1000 m downstream of the engine.

FIG. 5. Additional distributions of organic concentrations at the engine exit plane selected for our parametric study for the effect of initial organic concentration.

FIG. 6. Effect of organic distribution at the engine exit plane on the soot properties at 1000 m downstream of the engine.

FIG. 7. Effect of dry mass accommodation coefficients for (a) water soluble organic species and (b) water insoluble organic species on the soot properties at 1000 m downstream of the engine.

FIG. 8. Effect of wet mass accommodation coefficients for (a) water soluble organic species and (b) water insoluble organic species on the soot properties at 1000 m downstream of the engine.