High-Pressure Turbulent Flame Speeds and Chemical Kinetics ......Project Overview There are Five...
Transcript of High-Pressure Turbulent Flame Speeds and Chemical Kinetics ......Project Overview There are Five...
Eric L. PetersenDepartment of Mechanical Engineering
Texas A&M University
High-Pressure Turbulent Flame Speeds and Chemical Kinetics of Syngas Blends With and
Without Impurities
2014 University Turbine Systems Research WorkshopWest Lafayette, IN
21-23 October, 2014
3-Year Project Began in October, 2013
Project Overview
Project Highlights:
1. Duration: Oct. 1, 2013 – Sept. 30, 2016
2. DOE NETL Award DE‐FE0011778
3. Budget:$498,382 DOE + $124,595 Cost Share
4. Principal Investigator: Dr. Eric L. Petersen
Project Overview
This Project Addresses Several Problems for HHC Fuels
1. Improve NOx kinetics for High-Hydrogen Fuels at Engine Conditions
2. Effect of Contaminant Species on Ignition and Flame Speed
3. Impact of Diluents on Ignition Kinetics and Flame Speeds
4. Data on Turbulent Flame Speeds at Engine Pressures
Project Overview
There are Five Main Work Tasks for the Project
Work Tasks:
Task 1 – Project Management and Program Planning
Task 2 – Turbulent Flame Speed Measurements at Atmospheric Pressure
Task 3 – Experiments and Kinetics of Syngas Blends with Impurities
Task 4 – Design and Construction of a High-Pressure Turbulent Flame Speed Facility
Task 5 – High-Pressure Turbulent Flame Speed Measurements
TAMU Work is a Team Effort of Several People
Dr. Olivier Mathieu
Anibal Morones
Dr. Sankar Ravi
Charles Keesee
Clayton Mulvihill
Josh Hargis
5
Project Overview
Task 2 – Turbulent Flame Speed Measurements at Atmospheric Pressure
1-atm Turbulent Flame Speed Measurement will Build Upon Tests Done in Previous UTSR Project
• Utilize Existing Turbulent Flame Speed Hardware
• Extend Test Conditions to a Range of u' and Length Scale Values
• Design Test Matrices for Syngas Blends
• Perform Experiments for Syngas Blends at 1 atm Conditions
Task 2 – Turbulent Speeds
Existing Rig Characterized for One Main Condition
Task 2 – Turbulent Speeds
Features:
• 7075-T6 Heat-Treated Aluminum
• 4 radial impellers
• Diameter: 30.5 cm
• Length: 35.6 cm
• Window Port Diameter: 12.7 cm
• Maximum initial pressure: 1 atm
• Maximum initial temperature: 298 K
Turbulence:
• Intensity: 1.5 m/s rms
• Integral length scale: 27 mm
Recent Experiments Include Effect of Hydrocarbonson H2-Based Mixtures
• Mixtures Studied: 100% H2Syngas (50:50 H2/CO)50:50 H2/CH4
• 3 repeats per condition, typically
Task 2 – Turbulent Speeds
Global Displacement Speeds for Various
Recent Data Cover a Wide Range of Flamelet Regions
Task 2 – Turbulent Speeds
10-1 100 101 102 103 10410-1
100
101
102
103
CH4
Syngas50-50 CH4-H2
H2
Distributed Reactions
Thin Reaction Zone
Corrugated Flamelet
Wrinkled Flamelet
Da =1
u'/S
L
L/l
Ka = 1Re
L = 1
u' = SLLaminarFlame
Extensive Turbulence Field Characterization UnderwayUsing LDV System
Task 2 – Turbulent Speeds
-60 -40 -20 0 20 40 60-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
RMS velocity
Vertical Horizontal
Vel
ocity
[m/s
]
Distance from center [mm]
LDV measurements along cylindrical axis
Average velocity
Task 3 – Experiments and Kinetics of Syngas Blends with Impurities
1. Study Impurity Composition Effect
• Ignition delay time (ign) measurements in a shock tube
• Laminar flame speed measurements
• Large range of P, T
2. Kinetics Modeling of Impurities
Overall Task Has 2 Main Goals
Task 3 – Impurity Effects
1. Impurity Effect on Ignition {NH3, H2S, H2O, CO2, CH4} for Coal Syngas
2. Hydrocarbon Effect on Laminar Flame Speeds
Update Today Will Focus on 2 Main ProjectsTask 3 – Impurity Effects
Mixture derived from averaging 40 real coal syngas
Mixture
• Baseline (BS): (60 CO / 40 H2)/O2 (Krecji, Petersen et al., 2013)
• Baseline + others• (98.47%)BS + (1.53%)CH4
• (91.35%)BS + (8.65%)CO2
• (99.50%)BS + (0.50%) H2S
• Full Coal Syngas : (60 CO / 40 H2) + CH4+ CO2 + H2O• (28.76%)H2+(39.73%)CO+(1.50%)CH4+(9.00%)CO2+(21.00%)H2O
• Full Coal Syngas + impurities• (97.87%)Full Coal Syngas+(1.70%)NH3 +(0.43%)H2S
ELP2
Slide 15
ELP2 there is too much information on this one slide. It will be more effective to break it up into two slides, one on the mixture and one on the experimental conditions.
In fact, the mixture slide should be after the "Objectives" slide, before the shock tube details section.Eric Petersen, 3/6/2014
Investigated in dilute conditions at three pressures
Test Conditions
• Diluted conditions: 98 - 97.975% Ar
• Equivalence ratio: 0.5
• Pressure: 1.7, 13, and 32 atm
High-Pressure Shock-Tube Facility
• 1 – 100 atm Capability
• 600 – 4000 K Test Temperature
• Up to 20 ms Test Time
• 2.46 m Driver and 4.72 m Driven
• 15.24 cm Driven Inner Diameter
Time-Interval Measurement
Vacuum System
Driven Section (4.72 m) Driver Section (2.46 m)
Expansion Section / Diaphragm Location
Access PortWeldless Flange6
Shock-Tube ApparatusHigh pressure shock-tube facility at Texas A&M
0 0.0004 0.0008 0.0012Time (s)
0
0.4
0.8
1.2
Nor
mal
ized
OH
* em
issi
on
0
1
2
3
Pres
sure
(atm
)ign
Ignition Delay Time Obtained from OH* Time History
Measurement
Concave Reflecting Mirror (f)
Adjustable width slit
Optical Window
PMT
Shock tube
OH*
• A2 Σ+ (OH*) light at 307 nm
• Highly Diluted Mixtures (98% Ar)
Water can condense and change mixture composition
Condensation Problem
• Condensation of H2O during filling process
• Absorption onto shock tube walls
• Uncertainties in H2O concentration in tank mixture
Full Coal Syngas Fuel Mixture:(28.76%)H2+(39.73%)CO+(1.50%)CH4+(9.00%)CO2+(21.00%)H2O
To Vacuum System
Mixing Tank
Water Vial
Valves
Condensationat Access Port
Wall Absorption
Water concentration measured by laser light absorption
Measurement
• 1+3 transition band absorption
• Near 1387.877 nm
• Highly Diluted Mixtures (98% Ar)
Water concentration measured by laser light absorption
Measurement
Measured concentration within 5% of target value
0 100 200 300 400 5000.0
0.2
0.4
0.6
0.8
1.0 Mixture TDL Measurement
H2O
Vap
or P
ress
ure
(Tor
r)
Mixture Pressure (Torr)
Only H2S addition has a noticeable effect at low temperatures
Results – 1.7 atm
6 8 105 7 9
104/T5 (K-1)
100
1000
Igni
tion
dela
y tim
e (
s)1.75 0.25 atm, 98% Ar
H2/O2 60 CO/40 H2 (BS)BS-CO2BS-CH4BS-H2SCoal syngasCoal syngas-imp
(1000 K)(2000 K)
ign shorter for the full mixture at high temperatures
Results – 13 atm
7 8 97.5 8.5
104/T5 (K-1)
10
100
1000
Igni
tion
dela
y tim
e (
s) 13.3 1.0 atm, 98% Ar
H2/O2 60 CO/40 H2 (BS)BS-CO2BS-CH4BS-H2SCoal syngasCoal syngas-imp
(1429 K) (1111 K)
All mixtures have similar behavior at 32 atm
Results – 32 atm
7.5 8 8.57.75 8.25 8.75
104/T5 (K-1)
100
1000
Igni
tion
dela
y tim
e (
s)32.3 2.0 atm, 98 % Ar
H2/O2 60 CO/40 H2 (BS)BS-CO2BS-CH4BS-H2SCoal syngasCoal syngas-imp
(1333 K) (1143 K)
• C0-C4 from Wang et al., 2007 (USCII)
• C0-C1 from Li et al., 2007 (Princeton)
• Small HC mechanisms from Konnov, 2009
• C0-C3 from Metcalfe et al., 2013 (NUI Galway)
• Addition of the OH* sub-mechanism from Hall and Petersen, 2006 (if needed)
Comparison of the data with literature mechanisms
Model
NUIG and PRCT Models Agree Best with Data atHigher Pressures
Model - Results
NUI Galway
Konnov
USCII
Princeton
Disagreement at 13 atm and high temp. for the Coal syngas
5 6 7 8 9 1010
100
1000
Igni
tion
dela
y tim
e (
s)
7 7.5 8 8.5 9104/T5 (K-1)
10
100
1000
7.6 8 8.4 8.8
Baseline - 1.7 atm Baseline - 12.6 atm Baseline - 31.5 atm
Coal Syngas - 32.6 atmCoal Syngas - 13.2 atmCoal Syngas - 1.7 atm
Mixtures with H2S Impurity Were Also Modeled
• CO/H2 Chemistry from Metcalfe, Curran et al. (2013)
• H2S Chemistry from Mathieu, Petersen et al. (2014)
• OCS from Glarborg and Marshall (2013)
Model - Results
6 7 8 9 10104/T5 (K-1)
100
1000
Igni
tion
dela
y tim
e (
s)
= 0.5BS-H2S, 1.8 atmBS-H2S, 12.4 atmBS-H2S, 32.4 atmLines: model
BS CO/H2 mixture with H2S
1. Coal-Syngas and Bio-Syngas Blend Baselines
• Coal: 40/60 H2/CO
• Bio: 50/50 H2/CO
2. Coal Syngas with 1.6%, 7.4% CH4
3. Coal Syngas with 1.7% C2H6
4. Bio Syngas with 5%, 15% CH4
5. Bio Syngas with 1.6% C2H6
Laminar Flame Speed Study Focused on Hydrocarbons
Task 3 – Impurity Effects
Baseline Mixtures and Model Show Good Agreement
Task 3 – Impurity Effects
0.5 1.0 1.5 2.0 2.5 3.00
20
40
60
80
100
120
140
160
180
200
S L,
u (cm
/s)
Aramco Model, Bio-Neat Data, Bio-Neat Aramco Model, Coal-Neat Data, Coal-Neat
Model: AramcoMech 1.3Coal
Bio
0.5 1.0 1.5 2.0 2.5 3.00
20
40
60
80
100
120
140
160
180
S L,
u (cm
/s)
Aramco Model, Coal-Neat Data, Coal-Neat Aramco Model, Coal-1.6% CH4 Data, Coal-1.6% CH4 Coal-Ethane, Aramco Model Data-Coal-1.7% Ethane Aramco Model, Coal-7.4% CH4 Data, Coal-7.4% CH4
Coal-Derived Syngas Results
Task 3 – Impurity Effects
1.6% CH4
neat
1.7% C2H6
7.4% CH4
Bio-Derived Syngas Results
Task 3 – Impurity Effects
0.5 1.0 1.5 2.0 2.5 3.00
20
40
60
80
100
120
140
160
180
200
S L,
u (cm
/s)
Aramco Model, Bio-Neat Data, Bio-Neat Bio-0.8% Ethane, Aramco Model Data-Bio-0.8% Ethane Aramco Model, Bio-5% CH4 Data, Bio-5% CH4 Aramco Model, Bio-15% CH4 Data, Bio - 15% CH4
5% CH4
neat
0.8% C2H6
15% CH4
Model Good at Extremes but Improvements Needed For Blends
Task 3 – Impurity Effects
0.5 1.0 1.5 2.0 2.5 3.00
20406080
100120140160180200220240260280300
S L,
u (cm
/s)
Pure H2
CH4
Coal Syngas
7.4% CH4
• Completed Numerical Study of Effect of Impurities (NOx, H2S) on Syngas Blend Kinetics at Real Engine Conditions
• Applying OH Laser Absorption Diagnostic in Collaboration with Aerospace Corporation (Los Angeles, CA)
• Set up “New” Shock Tube at TAMU (inherited from Aerospace Corporation)
• Finished Kinetics Mechanism for NOx and Ammonia Chemistry with H2/CO
Task 3 – Impurity Effects
Several Other Tasks Have been Completed or are Underway
Aerospace Shock Tube Has Been Installed at TAMU
900 1000 1100 1200 1300 1400 1500
0.0
0.4
0.8
1.2
1.6
Reflected Shock
Pres
sure
(atm
)
Time (s)
Incident Shock
100% ArgonP = 0.89 atmT = 2589 K
Task 3 – Impurity Effects
Task 4 – Design and Construction of a Turbulent Flame Speed Facility
10-1 100 101 102 103 10410-1
100
101
102
103
104
Methane Hydrogen Syngas (50:50 H2:CO)
Da =10
Ka = 100
ReT = 10 4
ReT = 10 3
u'/S
L
L/L
ReT = 1
Da = 1
Ka = 1
Gas Turbine Conditions and Proposed Hi-P Rig Domain
LaminarFlames
Current RigDomain
Hi-P (SLL)
Task 4 – New Facility
Borghi Diagram shows Current and Desired Regions for Turbulent Flame Speeds
New Facility Will be Designed and Built at TAMU
1. Detailed Design and Structural Analysis
2. Fabrication of Vessel Components
3. Installation of Vessel
4. Characterization of Flow Conditions
Task 4 – New Facility
Task 4 Design Effort is Underway
• Survey of Existing Turbulent Flame Speed Facilities Completed
• Trade-off Study for Final Design Finished
• Critical Aspect is how to Handle or Reduce the Overpressure
• Will Move Toward a Design that Involves a Blowout Disk and Reservoir for Overpressure
• Detail Design is Underway
Task 4 – New Facility
New Design Will Utilize a Pressure Relief System
Task 4 – New Facility
Flame bomb Duct Expansion
tank
Pressure release device (vent)
0.0 0.2 0.4 0.6 0.8 1.00
1
2
3
4
5
6
7
8
9
Pre
ssur
e [b
ar]
Time [s]
Confined deflagration overpressure
Vent opens
Confined
Vented
• Max Initial Pressure: 30 atm
• Vessel Size: ~ 30.5 cm Dia (12 in)
• Motor and Fans similar to existing rig
Conceptual Design is Complete
Task 4 – New Facility
Flange for Mating with Vent Volume
Observation WindowFan Motors
Timeline Showing Task 4
now
Task 4 – New Facility
Task 5 – High-Pressure Turbulent Flame Speed Measurements
High-Pressure Experiments Will be Performed for Selected Syngas Blends
• Identify Two Test Matrices (Fuel Blends) for Study
• Utilize Results from Tasks 2 and 3 for Guidance
• Perform Experiments at Elevated Pressures
• Parallel High-Pressure Laminar Tests Should also be Done
Task 5 – High-Pressure Turbulence
Timeline Showing Task 5
now
Task 5 – High-Pressure Turbulence
Progress on the Five Main Work Tasks for the Project Was Presented
Task 1 – Project Management and Program Planning
Task 2 – Turbulent Flame Speed Measurements at Atmospheric Pressure
Task 3 – Experiments and Kinetics of Syngas Blends with Impurities
Task 4 – Design and Construction of a High-Pressure Turbulent Flame Speed Facility
Task 5 – High-Pressure Turbulent Flame Speed Measurements
Summary