Dynamics of Soot Mobility Size during Agglomeration & Surface Growth

Transcription

1 Dynamics of Soot Mobility Size uring Agglomeration & Surface Growth Georgios A. Kelesiis, Eirini Goueli, Sotiris E. Pratsinis Particle Technology Laboratory, ETH Zürich, Switzerlan (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster»)

2 Why care about mobility size? Higher Particle Deosition Fraction for lower m [3] C / log( m ) / C tot Nuclei Moe: Nascent Soot Conensation of toxic volatile secies [4,5] SO 4-2 Accumulation Moe: Mature Soot m [2] ρ eff = g [1] m π 6 m 3 Mass-base Number-base Mobility Diameter, m, nm [1] Kittelson DB. (1998) J. Aerosol Sci. 29, 575. moifie [2] Koylu Platzhalter UO, Faeth Logo/Schriftzug GM, Farias TL, Carvalho MG. (2007) Combust. Flame 100, 621. [3] Rissler (Anassung J, Swietlicki im Folienmaster: E, Bengtsson Menü A, Boman «Ansicht» C, Pagels «Folienmaster») J, Sanström T, Blomberg A, Lönahl J. (2012) J. Aerosol Sci. 48, 18. [4] De Filio A, Maricq MM. (2008) Env. Sci. Technol. 42, [5] Peata P, Stoeger T, Zimmermann R, Peters A, Oberörster G, D Anna A, (2015) Part. Fibre Toxicol. 12, 1. gkelesiis@tl.mavt.ethz.ch

3 1cm 1cm 1cm tuying Soot Formation in Flames Free Premixe an Diffusion flames: Oxiation McKenna Burner [1] Güler Burner [2] Quenche flames: Agglomeration N 2 flow with T = 298 K Surface Growth Burner-Stabilize Stagnation flame [3] CAST Soot Generator [4] [1] [2] combustion.mie.utoronto.ca/ [3] Camacho Platzhalter J, Liu Logo/Schriftzug C, Gu C, Lin H, Huang Z, Tang Q, You X, Saggese C, Li Y, Jung H, Deng L, Wlokas I, Wang H. (2015) Combust. (Anassung Flame im Folienmaster: 162, Menü «Ansicht» «Folienmaster») [4] Incetion Better gkelesiis@tl.mavt.ethz.ch Moeling? 3

4 Moeling of Soot Mobility Size N / log( m ), cm -3 [1] Mobility Diameter, m, nm Poulation Balance Agglomerates: Sorensen [3], transition regime m 0.46, n Kn Kn 10 n, n > 100 Aggregates? n Polyiserse PPs? Exeriment 100 m [1] Saggese C, Ferrario S, Camacho J, Cuoci A, Frassolati A, Ranzi E, Wang H, Faravelli T. Wang H. (2015) Combust. Flame 162, [2] Koylu (Anassung UO, Faeth im GM, Folienmaster: Farias TL, Menü Carvalho «Ansicht» MG. (2007) «Folienmaster») Combust. Flame 100, 621. [3] Sorensen CM. Aerosol Sci. Tech. (2011) 45, 765. [2] Nee for: m = Const g Goal: New m relationshi for: gkelesiis@tl.mavt.ethz.ch g m = f (n, ) i) Surface Growth/ Aggregation ii) PP Size Distribution

5 Soot Dynamics by Mesoscale Simulations i) Initial Configuration after Incetion rimarily stos [1,2]: T = 1830 K m,o = 2 nm N tot,o = m -3 [1,2] ii) Discrete Element Moeling (DEM) of Particle Motion an Agglomeration [3] t Poster Session Toay, : [1] Abi AD, Heinz N, Tolmachoff ED, Phares DJ, Cambell CS, Wang H. (2008) Combust. Flame 154, 775. [2] Camacho J, Liu C, Gu C, Lin H, Huang Z, Tang Q, You X, Saggese C, Li Y, Jung H, Deng L, Wlokas I, Wang H. (2015) Combust. Flame 162, [3] Goueli E, Eggersorfer ML, Pratsinis SE. (2015) Langmuir 31,1320. [4] Ael J, Bockhorn H, Frenklach M. (2000) Combust. Flame 121, 122. [5] Frielaner SK. (2000) Smoke, Dust, an Haze: Funamentals of Aerosol Dynamics. Oxfor University Press, New York. [6] Kelesiis GA, Goueli E, Pratsinis SE. (2017) Proc. Combust. Inst. 36, 29.

6 Soot Dynamics by Mesoscale Simulations i) Initial Configuration after Incetion rimarily stos [1,2]: T = 1830 K m,o = 2 nm N tot,o = m -3 [1,2] ii) Discrete Element Moeling (DEM) of Particle Motion an Agglomeration [3] iii) Surface Growth (SG) by HACA mechanism [4-6]: H 2 C 2 H 2 H Soot r HACA [4] β C2H2 [5] [1] Abi AD, Heinz N, Tolmachoff ED, Phares DJ, Cambell CS, Wang H. (2008) Combust. Flame 154, 775. [2] Camacho J, Liu C, Gu C, Lin H, Huang Z, Tang Q, You X, Saggese C, Li Y, Jung H, Deng L, Wlokas I, Wang H. (2015) Combust. Flame 162, [3] Goueli E, Eggersorfer ML, Pratsinis SE. (2015) Langmuir 31,1320. [4] Ael J, Bockhorn H, Frenklach M. (2000) Combust. Flame 121, 122. [5] Frielaner SK. (2000) Smoke, Dust, an Haze: Funamentals of Aerosol Dynamics. Oxfor University Press, New York. [6] Kelesiis GA, Goueli E, Pratsinis SE. (2017) Proc. Combust. Inst. 36, 29. Mass Balance for each C 2 H 2 reaction: , new, ol soot soot m2c

7 Mean Mobility Diameter, m, nm Soot Aggregation Dynamics by DEM // Primary Particle Diameter,, nm 300 Mature Soot 200 σ g, = 1.2 m 100 Nascent Soot Resience time, t, ms

8 Mean Mobility Diameter, m, nm // Diameter of gyration, g, nm Soot Aggregation Dynamics by DEM 300 Mature Soot g 200 m 100 Nascent Soot Resience time, t, ms

9 m vs g m g Resience time, t, ms [1] 40 % DEM, This work 30 % Mean Number of Primary Particles, n [1] Mealia AI. Power Technol. (2011) 4, 117. [2] Johnson DL, Leith D, Reist PC. J. Aerosol Sci. (1987) 18, 87. [3] Wang GM, Sorensen CM. Phys. Rev. (1999) E60, [2] DLCA [3]

10 DEM-erive istribution of m over n Normalize Mobility Diameter, m / DEM-erive Power Law: (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster») m 0.45 n [5] t = 600 ms Kn = 4 t = 100 ms Kn = 16 t = 15 ms Kn = Number of Primary Particles, gkelesiis@tl.mavt.ethz.ch n

11 Moment of Truth! Normalize Mobility Diameter, m / Exeriments: Diffusion Flames [1] CAST Soot Generator [2] Moels: Agglomerates [3] (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster») [5] Goo agreement for small sizes 37 % Overestimation Number of Primary Particles, n gkelesiis@tl.mavt.ethz.ch [1] Rissler J, Messing ME, Malik AI, Nilsson PT, Norin EZ, Bohgar M, Sanati M, Pagels JH. (2013) Aerosol Sci. Technol. 47, 792. [2] Yon J, Bescon A, Ouf FX. (2015) J. Aerosol Sci. 87, 28 [3] Sorensen CM. Aerosol Sci. Technol. (2011) 45, 765. σ g, =

12 Moment of Truth! Normalize Mobility Diameter, m / Exeriments: Diffusion Flames [1] CAST Soot Generator [2] Moels: Agglomerates [3] This work, [5] Aggregates Number of Primary Particles, n gkelesiis@tl.mavt.ethz.ch (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster») [1] Rissler J, Messing ME, Malik AI, Nilsson PT, Norin EZ, Bohgar M, Sanati M, Pagels JH. (2013) Aerosol Sci. Technol. 47, 792. [2] Yon J, Bescon A, Ouf FX. (2015) J. Aerosol Sci. 87, 28 [3] Sorensen CM. Aerosol Sci. Technol. (2011) 45, 765. σ g, = 1 m 0.45 n 6 % overestimation σ g, =

13 What about the Effective Density? Scaling law accounting for PP aggregation & olyisersity: eff bulk m 0.78 But is it any goo? Poster Session, Toay, (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster») gkelesiis@tl.mavt.ethz.ch

14 Conclusions Agglomeration & surface growth moeling reveals: m Const g New relationshi accounting for aggregation an olyisersity: m 0.45 n Chemical Boning of rimary articles is neee for m! (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster») gkelesiis@tl.mavt.ethz.ch

15 Thank you for your attention! Full Story in: Kelesiis GA, Goueli E, Pratsinis SE, Morhology an Mobility Diameter of Carbonaceous Aerosols uring Agglomeration & Surface Growth Carbon, 121, (Anassung im Folienmaster: Menü «Ansicht» «Folienmaster»)