Parameterization of H₂SO₄ and organic contributions to volatile PM in aircraft plumes at ground idle

Figures & data

Table 1. Surrogate Organic species profiles

Case	Label	C5H10O2	C10H8	C14H10	C16H10	C20H12	C22H12
Baseline	Nom/Nom	26.5	26.5	32.2	11.8	2.6	0.4
Nominal/Low	Nom/Low	26.5	26.5	32.2	12.0	2.6	0.2
Low/Low	Low/Low	26.5	26.5	32.2	13.3	1.3	0.2

Figure 1. The flow temperatures and velocities calculated with NPSS are compared for the CFM56 and the V2527 across a range of power conditions (100, 85, 65, 30, 7, and 4% rated thrust). While the trends are similar for both engines, the distinct values are different, especially for the core, due to the differing designs of these two engines.

Figure 2. The time histories, plotted versus downstream distance, of the condensed species in the droplet mode is tracked versus downstream distance. The total HC concentration is 400 ppbv and the Nom/Nom profile cases are shown for 4 sulfur levels. The 5 ppmm FSC level did not form droplets, so no curves are present in the figure for this case.

Figure 3. The lower panel (3b) shows the formation and growth of embryos, which form the nuclei which also grow to become the droplets shown in the upper panel (3a). These are for the case 400 ppbv HC with a Nom/Nom profile and 100 ppmm FSC for the V2527 engine.

Figure 4. As Figure 3, the lower panel (4b) shows the formation and growth of embryos, which form the nuclei which also grow to become the droplets shown in the upper panel (4a). These are for the case 400 ppbv HC with a Nom/Nom profile and 1000 ppmm FSC for the V2527 engine.

Figure 5. The EI_num for the droplet mode is plotted versus downstream distance for the V2527 engine for the HC 400 ppbv, Nom/Nom profile case with a range of FSCs: Panel a) 100, Panel b) 600, and Panel c) 1000 ppmm

Figure 6. The partitioning of H₂SO₄ between the gas, droplet, and soot coating phases is shown versus downstream distance for the 400 pmmv, Nom/Nom, and FSC = 100 ppmm case for the V2527 engine.

Figure 7. SO₄ content of droplets as a function of FSC at 250 m

Figure 8. SO₄ content of soot coatings as a function of FSC at 250 m

Figure 9. HC content of droplets as a function of HC and FSC at 250 m

Figure 10. HC content of soot coatings as a function of HC and FSC at 250 m

Figure 11. Number Density of droplets as a function of FSC at 250 m

Figure 12. SO₄ content of droplets as a function of FSC at 1000 m

Figure 13. SO₄ content of soot coatings as a function of FSC at 1000 m

Figure 14. HC content of droplets as a function of HC and FSC at 1000 m

Figure 15. HC content of soot coatings as a function of HC and FSC at 1000 m

Figure 16. Number Density of droplets as a function of FSC at 1000 m

Table 2. Ratio of EI_{273 K}/EI_{290 K} for H₂SO₄ and HCs for droplets and soot coatings at both 250 m (49.2 s) and 1000 m (13.05 min) for the “diagonal” matrix cases.

250 m	Sulfuric Acid		Organics
	Droplets	Soot	Droplets	Soot
HC113/S50	18.5	0.892	71.7	∞
HC400/S100	49.1	1.01	8.68	59.2
HC1333/S1000	203	0.122	1.58	18.3
1000 m	Sulfuric Acid		Organics
	Droplets	Soot	Droplets	Soot
HC113/S50	∞	0.311	642	∞
HC400/S100	515	1	23.9	41.9
HC1333/S1000	74.2	0.0909	1.5	10.4

Figure 17. The sulfuric acid and water content of the droplets

Figure 18. The organic content of the droplets

Figure 19. The number of droplets

Figure 20. The sulfuric acid and water content of the soot coatings

Figure 21. The organic content of the soot coatings

Data Availability Statement

The authors confirm that the data supporting the findings of this study are available within the article and its supplementary materials.