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

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


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


Global Displacement Speeds for Various

Recent Data Cover a Wide Range of Flamelet Regions


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


-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

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

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


(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


(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


Baseline Mixtures and Model Show Good Agreement


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


1.6% CH4

neat

1.7% C2H6

7.4% CH4

Bio-Derived Syngas Results


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


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


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 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 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


New Design Will Utilize a Pressure Relief System


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


Flange for Mating with Vent Volume

Observation WindowFan Motors

Timeline Showing Task 4

now


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 4 – Design and Construction of a High-Pressure Turbulent Flame Speed Facility


Summary

high-pressure turbulent flame speeds and chemical kinetics ......project overview there are five...

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