Modeling DME addition effects to fuel on PAH and soot in laminar coflow ethylene/air diffusion flames using two PAH mechanisms

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

z,

cm

volfrac(ppm) 8.00 7.80 7.60 7.40 7.20 7.00 6.80 6.60 6.40 6.20 6.00 5.80 5.60 5.40 5.20 5.00 4.80 4.60 4.40 4.20 4.00 3.80 3.60 3.40 3.20 3.00 2.80 2.60 2.40 2.20 2.00 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00

(i) Pure C

₂

H

₄

8.374 ppm

0.14 ppm

(a)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

8.552 ppm

0.18 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

7.554 ppm

0.19 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

6.465 ppm

0.20 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

5.459 ppm

0.20 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

3.682 ppm

0.19 ppm

 

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

5.37 ppm

1.08 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

4.35 ppm

1.03 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

3.46 ppm

0.91 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

1.94 ppm

0.68 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

6.34 ppm

1.10 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

z,

cm

volfrac(ppm) 6.00 5.85 5.70 5.55 5.40 5.25 5.10 4.95 4.80 4.65 4.50 4.35 4.20 4.05 3.90 3.75 3.60 3.45 3.30 3.15 3.00 2.85 2.70 2.55 2.40 2.25 2.10 1.95 1.80 1.65 1.50 1.35 1.20 1.05 0.90 0.75 0.60 0.45 0.30 0.15 0.00

(i) Pure C

₂

H

₄

7.05 ppm

1.02 ppm

(b)

 

 

Fig. 1 Distributions of soot volume fraction calculated using the ABF mechanism, (a), and the

DLR mechanism, (b).

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

z,

cm

A4 2.00E-07 1.95E-07 1.90E-07 1.85E-07 1.80E-07 1.75E-07 1.70E-07 1.65E-07 1.60E-07 1.55E-07 1.50E-07 1.45E-07 1.40E-07 1.35E-07 1.30E-07 1.25E-07 1.20E-07 1.15E-07 1.10E-07 1.05E-07 1.00E-07 9.50E-08 9.00E-08 8.50E-08 8.00E-08 7.50E-08 7.00E-08 6.50E-08 6.00E-08 5.50E-08 5.00E-08 4.50E-08 4.00E-08 3.50E-08 3.00E-08 2.50E-08 2.00E-08 1.50E-08 1.00E-08 5.00E-09 0.00E+00

(i) Pure C

2

H

4

1.93E-7

(a)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

2.32E-7

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

2.29E-7

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

2.22E-7

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

2.14E-7

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

1.97E-7

 

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

z,

cm

A4 1.20E-06 1.17E-06 1.14E-06 1.11E-06 1.08E-06 1.05E-06 1.02E-06 9.90E-07 9.60E-07 9.30E-07 9.00E-07 8.70E-07 8.40E-07 8.10E-07 7.80E-07 7.50E-07 7.20E-07 6.90E-07 6.60E-07 6.30E-07 6.00E-07 5.70E-07 5.40E-07 5.10E-07 4.80E-07 4.50E-07 4.20E-07 3.90E-07 3.60E-07 3.30E-07 3.00E-07 2.70E-07 2.40E-07 2.10E-07 1.80E-07 1.50E-07 1.20E-07 9.00E-08 6.00E-08 3.00E-08 0.00E+00

(i) Pure C

₂

H

₄

9.75E-7

(b)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

1.14E-6

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

1.25E-6

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

1.31E-6

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

1.32E-6

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

1.25E-6

Fig. 2 Distributions of pyrene mole fraction calculated by the ABF mechanism, (a), and the ABF

mechanism, (b).

0

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1

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8

z,

c

m

volfrac(ppm) 0.80 0.78 0.76 0.74 0.72 0.70 0.68 0.66 0.64 0.62 0.60 0.58 0.56 0.54 0.52 0.50 0.48 0.46 0.44 0.42 0.40 0.38 0.36 0.34 0.32 0.30 0.28 0.26 0.24 0.22 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00

(i) Pure C

2

H

4

0.67 ppm

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

0.71 ppm

 

Fig. 3 Distributions of soot volume fraction calculated using the DLR mechanism

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1

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z,

c

m

A1 3.20E-04 3.12E-04 3.04E-04 2.96E-04 2.88E-04 2.80E-04 2.72E-04 2.64E-04 2.56E-04 2.48E-04 2.40E-04 2.32E-04 2.24E-04 2.16E-04 2.08E-04 2.00E-04 1.92E-04 1.84E-04 1.76E-04 1.68E-04 1.60E-04 1.52E-04 1.44E-04 1.36E-04 1.28E-04 1.20E-04 1.12E-04 1.04E-04 9.60E-05 8.80E-05 8.00E-05 7.20E-05 6.40E-05 5.60E-05 4.80E-05 4.00E-05 3.20E-05 2.40E-05 1.60E-05 8.00E-06 0.00E+00

(i) Pure C

₂

H

₄

2.73E-4

(a)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

3.96E-4

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

3.86E-4

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

3.64E-4

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

3.41E-4

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

3.05E-4

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

1.84E-3

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

1.90E-3

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

1.85E-3

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

1.72E-3

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

1.41E-3

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r, cm

0

1

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4

5

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8

z,

c

m

A1 1.60E-03 1.56E-03 1.52E-03 1.48E-03 1.44E-03 1.40E-03 1.36E-03 1.32E-03 1.28E-03 1.24E-03 1.20E-03 1.16E-03 1.12E-03 1.08E-03 1.04E-03 1.00E-03 9.60E-04 9.20E-04 8.80E-04 8.40E-04 8.00E-04 7.60E-04 7.20E-04 6.80E-04 6.40E-04 6.00E-04 5.60E-04 5.20E-04 4.80E-04 4.40E-04 4.00E-04 3.60E-04 3.20E-04 2.80E-04 2.40E-04 2.00E-04 1.60E-04 1.20E-04 8.00E-05 4.00E-05 0.00E+00

(i) Pure C

2

H

4

1.32E-3

(b)

Fig. 4 Distributions of benzene mole fraction calculated using the ABF mechanism, (a), and the

DLR mechanism (b).

β

0.0

0.1

0.2

0.3

0.4

No

rm

al

ized

p

e

a

k

A

4

m

o

le

f

ract

io

n

0.9

1.0

1.1

1.2

1.3

1.4

ABF

DLR

β

0.0

0.1

0.2

0.3

0.4

N

o

rm

al

iz

ed peak A1 m

o

le

f

rac

ti

on

0.9

1.0

1.1

1.2

1.3

1.4

1.5

ABF

DLR

(a)

(b)

 

 

 

Fig. 5 Variations of the normalized peak mole fractions of A1, (a), and A4, (b) with

the amount of DME addition to the fuel stream.

0

0.5

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r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

0.0493

0

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1

r, cm

0

1

2

3

4

5

6

7

8

z,

c

m

C2H2 5.00E-02 4.88E-02 4.75E-02 4.62E-02 4.50E-02 4.38E-02 4.25E-02 4.13E-02 4.00E-02 3.88E-02 3.75E-02 3.62E-02 3.50E-02 3.38E-02 3.25E-02 3.13E-02 3.00E-02 2.88E-02 2.75E-02 2.62E-02 2.50E-02 2.38E-02 2.25E-02 2.13E-02 2.00E-02 1.87E-02 1.75E-02 1.63E-02 1.50E-02 1.38E-02 1.25E-02 1.13E-02 1.00E-02 8.75E-03 7.50E-03 6.25E-03 5.00E-03 3.75E-03 2.50E-03 1.25E-03 0.00E+00

(i) Pure C

₂

H

₄

0.0490

(a)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

0.0482

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

0.0465

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

0.0445

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

0.0400

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

z,

c

m

C2H2 5.60E-02 5.46E-02 5.32E-02 5.18E-02 5.04E-02 4.90E-02 4.76E-02 4.62E-02 4.48E-02 4.34E-02 4.20E-02 4.06E-02 3.92E-02 3.78E-02 3.64E-02 3.50E-02 3.36E-02 3.22E-02 3.08E-02 2.94E-02 2.80E-02 2.66E-02 2.52E-02 2.38E-02 2.24E-02 2.10E-02 1.96E-02 1.82E-02 1.68E-02 1.54E-02 1.40E-02 1.26E-02 1.12E-02 9.80E-03 8.40E-03 7.00E-03 5.60E-03 4.20E-03 2.80E-03 1.40E-03 0.00E+00

(i) Pure C

₂

H

₄

0.055

(b)

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(ii) 6% DME

0.054

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iii) 12% DME

0.052

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(iv) 18% DME

0.050

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(v) 25% DME

0.048

0

0.5

1

r, cm

0

1

2

3

4

5

6

7

8

(vi) 37% DME

0.043

Fig. 6 Distributions of acetylene mole fraction predicted by the ABF mechanism, (a) and the

DLR mechanism, (b).