vortragstitel 1 kinetic mechanism for low pressure oxygen / methane ignition and combustion n.a....

Vortragstitel1

Kinetic Mechanism For Low Pressure Oxygen / Methane Ignition and Combustion

N.A. Slavinskaya, M. Wiegand, J.H. Starcke, U. Riedel, O.J.Haidn

Institute of Combustion Technology, Institute of Space Propulsion, German Aerospace Centre (DLR)

Folie 2Vortragstitel2

Introduction Methane in Aerospace Propulsion in Europe Kinetic Mechanisms for O2/CH4

Low Pressure Methane CombustionMechanism DevelopmentMechanism ValidationAnalysis

Pollution formation: CO, NOx, PAHConclusions & Outlook

OVERVIEW


CH4 - related Propulsion Activities in Europe

Development of detailed and reduced chemical kinetic schemes for

high pressure CH4/O2 combustion including the formation of soot

precursors (PAH) (EU FP6 project LAPCAT 1, closed 2008)

CFD modeling injection and combustion and nozzle performance

studies of CH4/O2 at low pressure using commercial and in-house CFD

tools (EU FP7 project GRASP, ongoing)

Chemical Kinetics Modeling and CFD modeling for CH4/O2 Ignition

(EU FP7 project ISP-1 , ongoing)

Establishment of CH4/O2 Thermodynamic and Transport Properties

Data Base (EU FP7 project ISP-1 , ongoing)

Numerical Studies and Chemical Modeling


CH4 - related Propulsion Activities in Europe

LOX/LCH4 and GOX/GCH4 ignition and combustion studies (EU FP7

project ISP-1, ongoing)

LOX/CH4 gas generator (fuel rich) ignition studies (EU FP7 project

LAPCAT II, ongoing)

CH4 film cooling (EU FP7 project ISP-1, ongoing)

LOX/CH4 staged combustion testing at P8 (FLPP, closed 2009)

LOX/CH4 subscale testing at FAST 2 (Avio, nat. program, closed

2009)

LOX / CH4 LM10-Mira demo testing at CADB (Avio, nat. program,

2011)

Experimental Studies


The detailed investigations of the interaction of the rocket plumes, i.e.

the exhaust gases, particles of the propellants with the atmosphere.

MOTIVATION

The final step of the reaction mechanism development is its extension to the NOx sub mechanism.

The large number of launches is foreseen, which exceeds by far the current launch rate of about 40 launches per year.

Numerical Studies and Chemical Modeling the possible formation of CO, CO2, NO, NO2, N2O, and PAHs.


Methane kinetic mechanisms and their validation data base

ISP-I operating conditions 0.001 atm < p < 1 atm and 0.5 < Ф < 3.0

Mechanism Ignition delay Flame speed JSR PFR Shock tube NOx formation

GRI 3.0 [5]

p = 1 - 84 atm

T5 = 1356 -1700 K

= 0.5 - 1.0

p = 1 - 20 atm

To = 298, 400 K

= 0.6–1-.6

p = 1.07 atm

= 1.0

p = 1– 2 atm

T5 =1400–2100 K

= 0.4–4.0

HCN, NO,

N2O, CN

p = 798 torr, T = 1165K

Leeds Mechanism [6, 7]

p = 1 - 4 ; 21 - 29 atm

T5 = 1400 - 2050 K

= 0.1 - 2.0

p = 1.0atm, To = 298K = 0.6–1.4

NO

P = 40 torr

Konnov mechanism [10]

p = 1 - 10 atm

To = 298 K

= 0.5–1-.6

Ignition delays N2O

p=1 - 14 atm T=1000-1600 K

Pyrolysis of Hydrazine p=5.9 - 7.5 atm T=1100-1600 K

RAMEC mechanism [11-13]

p = 40 – 260atm

T5 = 1040 -2870 K

= 0.5-6.0

Li-Williams mechanism

[14-16],

San Diego Mechanism

p = 1 – 150 atm

T5 = 1000 -2000 K

= 0.4 – 6.0

p = 1.0 atm

To = 298 K

= 0.6–6.0

Le Cong-Dagaut mechanism [18,19]

p = 1- 60 atm T5 = 1100–2800 K, = 0.5-1

p = 1.0 – 20.0 atm To = 298, 615K = 0.6–1.6

p = 1 - 10atm To=900–1400K = 0.1–0.6

p = 1, 2 atm T = 1100 K = 1

p = 1–79 atm T5=1400–2200 K = 0.5 - 1

NO,NO2 p=1 - 10 atm T=800-1100 K


Input Model: DLR_LS Mechanism

Sub Mechanism Species/

Reaction

Validation

Parameters

Validation Data

CH4/CH3OH/O2/

Air

46 / 398

(93 / 729)

p = 1- 60 bar,

f = 0,5 – 2,

T0 = 300 – 1200 K

Laminar flame speed,

Ignition delay times,

PAH/Soot Formation

• consistent hierarchical structure

• “first principals”

• continuous adaptation, validation and

optimization of the kinetic characteristics

Slavinskaya, Frank, Comb.Flame, 2009

Slavinskaya, Haidn, AIAA 2008-1012, 2008

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

ReactionModel

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

REACTIONMODEL

Chlorinated compounds


Aromatics, soot

Aromatics, soot

SOxSOx

NOxNOx

EthersEthers

Alcohols

AlcoholsEstersEsters

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

ReactionModel

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

REACTIONMODEL

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

ReactionModel

C 9 – C 16C9 – C 16

C7 -C8C7 -C8

……C 3

C 3

C 2C2

CH 4CH 4

COCO

H 2- O 2H 2- O 2

REACTIONMODEL



Aromatics, soot

Aromatics, soot

SOxSOx

NOxNOx



Aromatics, soot

Aromatics, soot

SOxSOx





Aromatics, soot

Aromatics, sootAromatics, soot

Aromatics, soot

SOxSOxSOxSOx

NOxNOxNOxNOx

EthersEthers

Alcohols


EthersEthers

Alcohols



New data provoked with the syngasactivities, validated on the syngas data

Update for H2/CO reactions: new data for reaction rates.

Mechanism reduction

Full model (47/311) for low pressure CH4Ignition,laminar flame, concentration profiles

NOx mechanism addition



Mechanism reductionMechanism reduction



NOx mechanism additionNOx mechanism addition

Mechanism development : strategy

A.Konnov Mechanism


Reaction Mean value ,d %

H + O2 = OH + O 8,22E-14 8,19

OH + H2 = H2O + H 2,12E-12 10,53

H2 + O =OH + H 3,54E-13 20,82

H+HO2 = H2 + O2 2,92E-11 35,10

H2O2 + H = HO2 + H2 1,11E-12 51,36

OH + OH (+M) =H2O2(+M) 3,05E-32 1,99

H + O2 (+M) = HO2 (+M) 1,01E-32 11,67

O2 + CO = CO2 + O 1,29E-22 33,90

CO + O (+M) =CO2 (+M) 6,58E-34 82,31

CO + OH =CO2 + H 2,55E-13 43,36

CO + HO2 =CO2 + OH 9,54E-16 56,95

HCO (+M) = H + CO (+M) 5,83E-14 30,20

Mean values and deviations for reaction rates in H2/CO subsystem calculated from data of 7 different reaction models at T=1000K

24

1

2,

~~24

1

jjignignign

iifiif kk ,,

~,

~

1.8 – 57.4 %

Slavinskaya Starke, Riedel, 2011, in preparation

for H2/CO mixtures


Review and actual data for reaction rates : H2/CO subsystem

2H+AR = H2+AR 2H+N2 = H2+N2 2H+H2O = H2+H2O 2H+H = H2+H OH+H2 = H2O+H 2OH(+M) = H2O2(+M) H2O2(+AR) = 2OH(+AR) H2O2(+N2) = 2OH(+N2) OH+OH (+ H2O) = H2O2 (+ H2O) O2+H(+M) = HO2(+M) O2+H(+AR) = HO2(+AR) O2+H(+H2O) = HO2(+H2O) H+O2(+HE) = HO2(+HE)

H+O2(+O2) = HO2(+O2) H+O2(+H2O) = HO2(+H2O) 2O+M = O2+M H+OH+M = H2O+M H+O+M = OH+M H+HO2 = H2+O2 H+HO2 = 2OH HCO+M = H+CO+M HCO + M = H + CO + M H2+O2 = OH + OH CO+O+M = CO2+M CO+HO2 = CO2+OH

Baulch, D.L., Cobos, C.J., 1994Wooldridge, M.S., Hanson R.K., et al.,1996 Isaacson, A.D., 1997 Karach, S.P., Osherov, V.I.,1999

Baulch, D.L., Bowman, C.T. et al., 2005 You, X., Wang, H., et al., 2007 Konnov, A., 2008Shatalov, O.P., Ibraguimova, L.B., et al.,2009


No Pressure Composition Experimental data

T0,K Ref.

1 0.5 atm CH4/ air Laminar flame speed

0.5 – 1.5 300 Hassan et al., 1997 [35]

2 1.76 – 2.40 bar CH4/ O2/ Ar Ignition delay time 1-2 1500- 1800 Seery et al.,1970, [36]

3 0.7- 0.9 atm CH4/ O2/ Ar Ignition delay time 1 1700 – 2200 Petersen et al., 2004 [37]

4 0.54 – 1.0 atm CH4/ H2/Air Ignition delay time 0.5 1130 – 2000 Petersen et al., 2007 [38]

5 25 – 30 Torr CH4/ O2/ Ar Concentration profiles

0.81– 1.28 400 – 2000 Berg et al., 2000 [39]

6 40 Torr CH4/ O2/ Ar Concentration

profiles 1 450 – 1800 Turbieza et al., 2004[40]

7 0.16 atm CH4/ air Laminar flame speed

0.8 – 1.3 300 Ombrello et al., 2011 [41]

8 1 atm CH4/ air NO concentration profile

0.5 300- 1800 Thomsen et al., 1999 [43]

9. 1 atm CH4/O2/NO/N2 CO, CO2, NO, NO2 concentration profile

0.1 800- 1150 Dagaut&Nicolle, 2005 [45]

10. 0.6 - 18 20%CO/ 80%H2 40%CO/ 60%H2 80%CO/ 20%H2

90%CO/ 10%H2

Ignition delay time 0.5 890 -1285 Kalitan et al., [46]

11 1.15 – 1.4 80%CO/ 20%H2 90%CO/ 10%H2

Ignition delay time 0.5, 0.9, and 1.0

909 - 965 Mertens, 2006, [47]

12 1 50%CO/ 50%H2 95%CO/ 5%H2

Laminar flame speed

0.5 – 6 300 [48 -50]

Mechanism validation: experimental data base


Mechanism validation: low pressure ignition

5.5 6.0 6.5 7.0

102

103

CH4/O

2/Ar

lgn

itio

n d

elay

, s

10000/T ,1/K

Exp. Seery et al.,1970 = 1, 2 p = 1.85 - 2.40 bar, p = 1.76 - 1.83 bar

2 bar / 1.8 bar / pw

0.5 0.6 0.7

100

1000

Exp., Petersen et al., 2007 calc. pw

Igni

tion

dela

y, m

ks

1000/T, 1/K

CH4/O

2/N

2

p = 0.54 - 0.92 atm = 0.36

2400 2200 2000 1800 1600 1400

0.50 0.55 0.60100

1000

Exp.,Petersen et al., 2004: ign

Exp.,Petersen et al., 2004: max OH Calc. pw

Igni

tion

dela

y, m

ks

1000/T, 1/K

CH4/O

2/AR

p = 0.8- 1.0 atm = 1.0

2400 2200 2000 1800 1600 1400


Mechanism validation: low pressure flame speed

0.50 0.75 1.00 1.25 1.5010

20

30

40

50

60

Exp., Hassa et al., 1997, p=0.5 atm Exp., Ombrello et al., 2011, p=0.16 atm

full model (47/311)skeletal model (24/103) T

0= 300 K

Lam

inar

flam

e ve

losi

ty, c

m/s

Exp. Ombrello et al., 2011, p=0.16 atm.


Mechanism validation: low pressure laminar flame

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

0

5

10

15

20

25

CH

, p

pm

Height above burner, cm

=1.07 =1.28 CH Exp. [37] CH, T, pw

p=25 Torr

400

600

800

1000

1200

1400

1600

1800

2000

Te

mp

era

ture

, K

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

1E-5

1E-4

1E-3

0.01

p=25 Torr

=1.07 =1.28 OH Exp. Berg et al.,, 2000 OH, pw

OH

mol

e fr

actio

n

Height above burner, cm

P = 25 Torr


a

b

c0 5 10 15 20

0.00

0.02

0.04

0.06

0.08

CH4/O

2/Ar laminar flame

p = 0.05 atm = 1.05

Exp., Tubiez et al., 2004 calc. pw

Mol

e fr

actio

n

Distance above the burner (mm)

CH4

d

Fig. 5: Comparison of modelled CH4, O2, CO and H2 concentration profiles with measured CH4/O2/Ar laminar premixed flame data [40], p = 0.05 atm, = 1.05. Lines – simulations with present mechanism.

0 5 10 15 200.0

4.0x10-2

8.0x10-2

1.2x10-1

1.6x10-1O

2

Mo

le f

ract

ion


0 5 10 15 200.00

0.02

0.04

0.06

CO

Mo

le f

ract

ion


0 4 8 12 16 20

5.0x10-3

1.0x10-2

1.5x10-2

2.0x10-2

2.5x10-2

3.0x10-2

H2

Mol

e fr

actio

n

Distance above the burner, mm

Mechanism validation: low pressure laminar flame, p=0.05 atm


a

b

c

d

Fig. 7: Comparison of modelled OH, CH3, HCO, H concentration profiles with measured CH4/O2/Ar laminar premixed flame data [40], p=0.05 atm, Ф=1.05. Lines – results with present mechanism.

0 2 4 6 8 10 12 14 16 18 200.0

2.0x10-5

4.0x10-5

6.0x10-5

8.0x10-5

1.0x10-4

1.2x10-4

Mo

le f

ract

ion

Distance above the Burner, mm

HCO

0 2 4 6 8 10 12 14 16 18 200.000

0.005

0.010

0.015

0.020

Mo

le f

ract

ion


H

0 5 10 15 200.000

0.002

0.004

0.006

0.008

0.010


CH4/O

2/Ar laminar flame

p = 0.05 atm = 1.05

OH

Mol

e fr

actio

n

Distance above the Burner [mm]0 5 10 15 20

0.000

0.001

0.002

0.003

0.004 CH3

Mol

e fr

actio

n




a

b

c

d

Fig. 6: Comparison of modelled CO2, H2O, C2H4, CH2O, C2H6 concentration profiles and measured CH4 /O2 /Ar laminar premixed flame data [40], p=0.05 atm, Ф=1.05. Lines – simulations with present mechanism.

0 5 10 15 20

0.00

0.02

0.04

0.06

0.08

CO2

Mol

e fr

actio

n


0 5 10 15 200.0

0.1

0.2

CH4/O

2/Ar laminar flame

p = 0.05 atm = 1.05


H2O

Mol

e fr

actio

n


0 2 4 6 8 10 12 14 16 18 200.0000

0.0001

0.0002

0.0003

0.0004

C2H4

Mo

le f

ract

ion

Distance above the Burner, mm 0 5 10 15 200.000

0.001

0.002

0.003

0.004

CH4/O

2/Ar laminar flame

p = 0.05 atm = 1.05

C2H6 CH2O

Mol

e fr

actio

n

Distance above the Burner [mm]



0 1 2 3 4 5 60

20

40

60

80

100

120

140

160

180

200

220 Mclean et al.,1994 Hassan et al.,1997 Sun et al., 2007

calc., pw

Lam

inar

flam

e sp

eed

/ cm

/s

p = 1bar T0 = 298K

50%CO/50%H2/air

95%CO/5%H2/air

10.4 10.6 10.8 11.0 11.2

10-3

10-2

Exp. / Calc. / p = 1.2bar (80%/20%) CO/H

2/N

2

/ p = 1.4bar (90%/10%) CO/H2/Ar

Igni

tion

Del

ay T

ime

/s

10000 K/T

7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.51E-5

1E-4

1E-3

0.01

Exp. Calc. / p=1 bar / p= 2-3 bar / p=14 -18 bar

Igni

tion

Del

ay T

ime

/ s

10000 K/T

80/20% CO/H2

7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.51E-5

1E-4

1E-3

0.01

10000 K/T

Igni

tion

Del

ay T

ime

/ s

Exp. Calc. / p=1 bar / p= 2.5 bar / p=13 -17 bar

90/10% CO/H2

Mechanism validation: CO/H2 sub mechanism


Mechanism validation: NOX sub mechanism

0 2 4 6 8 100

1

2

3

4

5

6

NO concentrations LIF calculations

Axial Height (mm)

NO

Co

nce

ntr

atio

n (

pp

m @

15

% 0 2)

0

200

400

600

800

1000

1200

1400

1600

1800

2000

Temperatures Measured calculations

Te

mp

era

ture

(K)

P = 1.00 atm = 0.6 Thomsen et a., 1999

CH4/air laminar premixed flame data , p = 1.0 atm,

Ф = 0.6.


Mechanism validation: NOX sub mechanism

800 900 1000 1100 12000.0000

0.0002

0.0004

0.0006

0.0008

0.0010

0.0012

0.0014

0.0016

0.0018

0.0020

Exp. Calc. CO CO2

Mo

le fra

ctio

n

T,K

p = 1 atmCH4/O2/NO/N

2

800 900 1000 1100 1200

0.000

0.001

0.002

0.003

0.004

0.005 Exp. Calc. CH4 H2O

T,K

Mo

le fra

ctio

n

800 900 1000 1100 12000.00000

0.00005

0.00010

0.00015

0.00020

0.00025

0.00030Exp. Calc.

NO2 NO

Mo

le fra

ctio

n

T,K

ac

JSR concentration profiles for CH4/O2/NO/N2 mixture, p = 1.0 atm, Ф = 0.1, residents time 120ms.

Dagaut, P., Nicolle, A.,2005


1 2 3 41 2 3 41 2 3 4

Reactor network chain schematic

Interaction of exhaust gas with the atmosphere

Model schematic for rocket engines


Reactor 1 Reactor 2 Mixer PFR air content air content Unit T

[K] p

[atm] T

[K] p

[atm] 5% 10% 20% 50% 5% 10% 20% 50%

Initial parameter 180 100 3626 100 Final parameter 3626 100 2867 0.25 +flowrate [kg/s] 35 78 175 700

Flow rate [kg/s] 700 700 735 778 875 1400

735 778 875 1400

0,01atm Temp [K] Temp [K] Initial parameter 180 100 3626 100 2867 2867 2867 2867 2865 2863 2858 2829

Final parameter 3626 100 2867 0.25 2865 2863 2858 2829 2666 2665 2664 2658

v [m/s] 3375 3376 3379 3393

0,05atm

Initial parameter 180 100 3626 100 2867 2867 2867 2867 2865 2863 2858 2829

Final parameter 3626 100 2867 0.25 2865 2863 2858 2829 2685 2677 2657 2455

v [m/s] 3407 3447 3530 3896

0,1atm

Initial parameter 180 100 3626 100 2867 2867 2867 2867 2865 2863 2858 2829

Final parameter 3626 100 2867 0.25 2865 2863 2858 2829 2766 2765 2765 2761

v [m/s] 3375 3376 3379 3393

Reactor input data for calculations

1 2 3 45%/10%/20%/50% a

ir

5%/10%/20%/50% air

1 2 3 41 2 3 45%/10%/20%/50% a

ir

5%/10%/20%/50% air


a

10-1 100 101 102 1032600

2650

2700

2750

2800

2850

2900

(s)

Te

mp

era

ture

, K

x(cm)

p = 0.01 atm (31 km)

1E-6 1E-5 1E-4 1E-3

5% air 10% air 20% air 50% air

b

10-1 100 101 102 1032600

2650

2700

2750

2800

2850

2900 (s)

T (

K)

x (cm)

5% air

p = 0.05 atm (20 km)

1E-6 1E-5 1E-4 1E-3

10% air 20% air 50% air

c

10-1 100 101 102 1032600

2650

2700

2750

2800

2850

2900 (s)

Tem

pe

ratu

re, K

x(cm)

p = 0.1 atm (16 km)

1E-6 1E-5 1E-4 1E-3


Fig. 15: Temperature profiles in the PFR calculated for different portions of air in exhaust under ambient pressures a ) p = 0.01 atm b) p = 0.05 atm c) p = 0.1 atm.

Simulations: Temperature distribution in exhaust


Simulations: CO and CO2 distribution in exhausta

10-1 100 101 102 1030.190

0.192

0.194

0.196

0.198

0.200


Mol

e fr

actio

n

x (cm)

1E-6 1E-5 1E-4 1E-3

p = 0.01 atm (31 km)

(s)

CO

b

10-1 100 101 102 1030.190

0.192

0.194

0.196

0.198

0.200

Mol

e fra

ctio

n

x (cm)

1E-6 1E-5 1E-4 1E-3

p = 0.05 atm (20 km)

(s)


CO

c

10-1 100 101 102 1030.190

0.192

0.194

0.196

0.198

0.200

Mol

e fra

ctio

n

x (cm)

1E-6 1E-5 1E-4 1E-3


p = 0.1 atm (16 km)

(s)

CO

Fig. 16: CO concentration profiles in the PFR calculated for different portions of air in exhaust under ambient pressures a ) p = 0.01 atm b) p = 0.05 atm c) p = 0.1 atm. a

10-1 100 101 102 1030.0870

0.0875

0.0880

0.0885

0.0890

0.0895

0.0900

5% air 10% air 20% air 50% airM

ole

fract

ion

x (cm)

1E-6 1E-5 1E-4 1E-3

p = 0.01 atm (31km)

(s)

CO2

b

10-1 100 101 102 1030.0870

0.0875

0.0880

0.0885

0.0890

0.0895

0.0900

Mol

e fra

ctio

n

x (cm)

1E-6 1E-5 1E-4 1E-3

p = 0.05 atm (20 km)

(s)


CO2

c

10-1 100 101 102 1030.0870

0.0875

0.0880

0.0885

0.0890

0.0895

0.0900

Mol

e fra

ctio

n

x (cm)

1E-6 1E-5 1E-4 1E-3


p = 0.1 atm (16 km)

(s)

CO2

Fig. 17: CO2 concentration profiles in the PFR calculated for different portions of air in exhaust under ambient pressures a ) p = 0.01 atm b) p = 0.05 atm c) p = 0.1 atm.

High concentration


Simulations: NO distribution in exhaust

a

10-1 100 101 102 1031E-7

1E-6

1E-5

1E-4

Mol

e fr

actio

n

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3


p = 0.01 atm (31 km)

(s)

NO

b

10-1 100 101 102 1031E-7

1E-6

1E-5

1E-4

Mo

le fr

act

ion

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3

p = 0.05 atm (20 km)

(s)


NO

c

10-1 100 101 102 1031E-7

1E-6

1E-5

1E-4

Mo

le fr

act

ion

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3


p = 0.1 atm (16 km)

(s)

NO

Fig. 18: NO concentration profiles in the PFR calculated for different portions of air in exhaust under ambient pressures a ) p = 0.01 atm b) p = 0.05 atm c) p = 0.1 atm.

High concentration


Simulations: NO2 distribution in exhaust

a

10-1 100 101 102 1031E-11

1E-10

1E-9

1E-8

1E-7

Mol

e fra

ctio

n

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3

p = 0.01 atm (31 km)

(s)


NO2

b

10-1 100 101 102 1031E-11

1E-10

1E-9

1E-8

1E-7

Mol

e fra

ctio

n

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3

p = 0.05 atm (20 km)

(s)


NO2

c

10-1 100 101 102 1031E-11

1E-10

1E-9

1E-8

1E-7

Mol

e fra

ctio

n

x (cm)

0.0 1.0x10-3 2.0x10-3 3.0x10-3

p = 0.1 atm (16 km)

(s)


NO2

Fig. 19: NO2 concentration profiles in the PFR calculated for different portions of air in exhaust under ambient pressures a ) p = 0.01 atm b) p = 0.05 atm c) p = 0.1 atm.

Low concentration


CONCLUSIONS

• Low Pressure O2/CH4 Kinetic Mechanisms developed as further extension of DLR_LS mechanism for operating conditions 0.03 atm < p < 1 atm, 300 K < T0 < 1800 K and 0.36 < Ф < 2.0

• Extension of Low Pressure Scheme towards Rocket Plume Chemistry (NOx, CO, PAHs)

• Simulations of the low pressure reactions in the exhaust plume of a CH4/LOX rocket engine under the strato- and mesosphere conditions (0.1 - 0.01 bar) shown that the relatively high amount of NOx and CO

• Simulations did not support the PAH formation under given conditions


Thanks you for your attention

AcknowledgmentsPart of this work was performed within the “ ISP-1” project, coordinated by SNECMA,

and supported by the European Union within the 7th Framework Program for Research & Technology. (Grant agreement N° 218849.)

Lots of thanks to Dr. Eric L. Petersen for the sent experimental data



Mechanism reduction


NOx mechanism addition

New data provoked with the syngasactivities, validated on the syngas data

vortragstitel 1 kinetic mechanism for low pressure oxygen / methane ignition and combustion n.a....

Documents

konnov mechanism slide

ignition eu fp7 project

chemical modeling slide

ongoing establishment

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