Skip to content

Ask the SI:

Experiments / ACME burners

Basic flame science

Flame Design

Measured when spherical gas flames start to make soot and when they go out, for both normal and inside-out flames.

NASA's own record
Nine spherical flames at different stages, from blue to sooty yellow.
Spherical flames from Flame Design. NASA photograph, from PSI.

What burned

Gas

Ethylene and propane

Where

On the space station

In orbit, where everything is weightless

How much data

327 tests

Each one is a row in NASA's table

What they changed between tests

  • oxygen concentration
  • pressure
  • fuel dilution
  • flow rate
  • flame direction

What it found

  1. The team proposed a single temperature below which a microgravity spherical flame goes out.

    NASA's words

    “Microgravity spherical diffusion flames extinguish when the peak temperature first decreases below 1130 K.” PSI record

Summarized by the SI. Each summary is tied to a quotation that the build checks against NASA's text. A matching quote is not a scientific review.

What it helps with

  • Stopping a fire from starting

    Which materials burn, and in what air

    Touches on it

  • Noticing a fire early

    What smoke looks like to a detector

    Not an aim

  • Putting a fire out

    What makes a flame go out

    Touches on it

For researchers: NASA's full recordThe conditions tested, every row of the table, NASA's description, publications and hardware
ISSMicrogravity InvestigationACME burnersCompare with othersdoi:10.60555/w4zy-bt45

Shared hardware: Six gas-flame experiments shared one modular set of burners and diagnostics. Experiments that shared hardware share its limits, so their results can be compared directly.

Why it counts as fire-safety research

“Other combustion investigations within the PSI database (but not explicitly referenced above) are still relevant to fire safety, just not as strongly or directly.” NASA challenge statement

NASA's words behind each rating

  • Prevention1 of 3

    “Evaluate whether pseudo-flammability limits can be obtained for these flames.”

  • Detection0 of 3

    Not an aim of this investigation.

  • Suppression1 of 3

    “Obtain extinction limits as functions of Zst, amount of N2, and pressure for normal and inverse spherical C2H4 and CH4 flames.”

Conditions covered

Oxygen in the atmosphere
19.8% to 40%
burner stream up to 85%
Pressure
43 kPa to 305 kPa
Flow speed
not reported
not in the PSI table
Itemized rows
327
327 tests

Fuels and materials

ethylene (307), propane (20)

Measurements named in the PSI record

  • Flame imaging
  • Radiometry
  • Thermocouples
  • Chemiluminescence
  • Soot measurement

How the tests differ, and how they are the same

Worked out from the 327 rows of the PSI table. A variable that is not listed was not reported, which is different from being held fixed.

Changed from test to test

Oxygen
19.8% to 85%
Oxygen refers to
2 different values
Pressure
43 kPa to 305 kPa
Fuel or material
2 different values
Fuel fraction
5% to 100%
Fuel flow rate
0.313 mg/s to 2.52 mg/sreported in 207 of 327 rows
Oxidizer flow rate
1.52 mg/s to 9.8 mg/sreported in 120 of 327 rows
Oxygen at end of test
19.7% to 39.7%reported in 187 of 327 rows
Adiabatic flame temperature
1,683 K to 2,974 K
Stoichiometric mixture fraction
0.0609 to 0.758
Photomultiplier tube 1 gain setting
4 to 7reported in 307 of 327 rows
Photomultiplier tube 3 gain setting
4 to 7reported in 307 of 327 rows

The same in every test

Fuel phase
gas
Geometry
spherical burner

Rows from the PSI table

Click a row for the source of every value. Filter and export

RecordTypeFuel or materialShapeOxygenPressureFlow, cm/sOutcomeDate
21328A1Testethylenespherical burner37.1%stream101 kPa
21328A2Testethylenespherical burner37.1%stream101 kPa
21328D1Testethylenespherical burner21.2%stream102 kPa
21328N1Testethylenespherical burner85%stream96.2 kPa
21328N2Testethylenespherical burner85%stream96.3 kPa
21328N3Testethylenespherical burner85%stream96.5 kPa
21328N4Testethylenespherical burner85%stream96.5 kPa
21328N5Testethylenespherical burner85%stream96.6 kPa
21328P1Testethylenespherical burner40.2%stream96.7 kPa
21340A1Testethylenespherical burner85%stream101 kPa
21340A2Testethylenespherical burner85%stream101 kPa
21340B1Testethylenespherical burner56.5%stream102 kPa
21340B2Testethylenespherical burner56.5%stream102 kPa
21340C1Testethylenespherical burner35.5%stream102 kPa
21340C2Testethylenespherical burner35.6%stream102 kPa
21340C3Testethylenespherical burner29%stream102 kPa
21340C4Testethylenespherical burner29.1%stream103 kPa
21340C5Testethylenespherical burner29.4%stream103 kPa
21340C6Testethylenespherical burner29.1%stream103 kPa
21340C7Testethylenespherical burner29.5%stream103 kPa
21340M1Testethylenespherical burner85%stream101 kPa
21340M2Testethylenespherical burner46.9%stream101 kPa
21349A1Testethylenespherical burner85%stream43 kPa
21349B1Testethylenespherical burner85%stream43.1 kPa
21349D2Testethylenespherical burner21.2%stream43.2 kPa
21349D3Testethylenespherical burner25.3%stream43.4 kPa
21349M1Testethylenespherical burner34.5%stream101 kPa
21349M2Testethylenespherical burner26.2%stream101 kPa
21349M3Testethylenespherical burner21.2%stream102 kPa
21349M4Testethylenespherical burnernot reportedstream103 kPa
21349M5Testethylenespherical burnernot reportedstream103 kPa
21349M6Testethylenespherical burnernot reportedstream104 kPa
21349M7Testethylenespherical burner50%stream105 kPa
21349N1Testethylenespherical burner50.2%stream50.8 kPa
21349N2Testethylenespherical burner32%stream51.1 kPa
21349N3Testethylenespherical burner21.2%stream51.4 kPa
21349N4Testethylenespherical burner21.2%stream52.3 kPa
21361A1Testethylenespherical burner85%stream101 kPa
21361B1Testethylenespherical burner85%stream102 kPa
21361C1Testethylenespherical burner43.3%stream102 kPa
21361C2Testethylenespherical burner43.4%stream102 kPa
21361D1Testethylenespherical burner27%stream102 kPa
21361D2Testethylenespherical burner27%stream103 kPa
21361F1Testethylenespherical burner85%stream101 kPa
21361F2Testethylenespherical burner85%stream101 kPa
21361F3Testethylenespherical burner85%stream101 kPa
21361F4Testethylenespherical burner85%stream102 kPa
21361F5Testethylenespherical burner85%stream102 kPa
21361F6Testethylenespherical burner85%stream102 kPa
21361G1Testethylenespherical burner57%stream102 kPa
21361G2Testethylenespherical burner57.2%stream102 kPa
21361G3Testethylenespherical burner57.2%stream102 kPa
21361G4Testethylenespherical burner36.4%stream102 kPa
21361G5Testethylenespherical burner36.6%stream102 kPa
21361M1Testethylenespherical burner43.5%stream101 kPa
21361M2Testethylenespherical burner27.1%stream101 kPa
21361M3Testethylenespherical burner85%stream102 kPa
22018A1Testethylenespherical burner85%stream101 kPa
22018B1Testethylenespherical burner85%stream101 kPa
22018C1Testethylenespherical burner56.9%stream101 kPa
22018D1Testethylenespherical burner45.6%stream101 kPa
22018F1Testethylenespherical burner36.5%stream102 kPa
22018G1Testethylenespherical burner85%stream101 kPa
22018G2Testethylenespherical burner85%stream101 kPa
22018G3Testethylenespherical burner85%stream102 kPa
22018H2Testethylenespherical burner49.7%stream102 kPa
22018J1Testethylenespherical burner31.8%stream102 kPa
22018J2Testethylenespherical burner85%stream102 kPa
22018J4Testethylenespherical burner46.1%stream103 kPa
22024A1Testethylenespherical burner85%stream101 kPa
22024A2Testethylenespherical burner85%stream101 kPa
22024B1Testethylenespherical burner85%stream102 kPa
22024C1Testethylenespherical burner64.4%stream102 kPa
22024D1Testethylenespherical burner41.2%stream102 kPa
22024F1Testethylenespherical burner25.6%stream102 kPa
22024B2Testethylenespherical burnernot reportedstream102 kPa
22024B3Testethylenespherical burnernot reportedstream102 kPa
22024G1Testethylenespherical burner85%stream50.6 kPa
22024H1Testethylenespherical burner85%stream50.7 kPa
22024J1Testethylenespherical burner64.4%stream50.8 kPa
22024K1Testethylenespherical burner41.2%stream50.9 kPa
22024L1Testethylenespherical burner25.6%stream51.1 kPa
22024L2Testethylenespherical burner32.7%stream51.2 kPa
22024L3Testethylenespherical burner41.3%stream51.4 kPa
22024H2Testethylenespherical burner85%stream51.5 kPa
22042M1Testethylenespherical burnernot reportedstream51.5 kPa
22024M2Testethylenespherical burnernot reportedstream51.8 kPa
22024K2Testethylenespherical burnernot reportedstream51.9 kPa
22024K3Testethylenespherical burnernot reportedstream52.4 kPa
22027B1Testethylenespherical burner85%stream304 kPa
22027B2Testethylenespherical burner85%stream304 kPa
22027B3Testethylenespherical burner85%stream304 kPa
22027B4Testethylenespherical burnernot reportedstream304 kPa
22027B5Testethylenespherical burner85%stream304 kPa
22027B6Testethylenespherical burner85%stream304 kPa
22027B7Testethylenespherical burner85%stream304 kPa
22027D1Testethylenespherical burner49.1%stream305 kPa
22027D2Testethylenespherical burner85%stream305 kPa
22027D3Testethylenespherical burner85%stream304 kPa
22027D4Testethylenespherical burner85%stream304 kPa
22027D5Testethylenespherical burner85%stream304 kPa
22027D6Testethylenespherical burner85%stream304 kPa
22027B8Testethylenespherical burnernot reportedstream304 kPa
22027C1Testethylenespherical burner49.8%stream304 kPa
22027C2Testethylenespherical burner31.9%stream304 kPa
22035A1Testethylenespherical burner85%stream200 kPa
22035B1Testethylenespherical burner85%stream200 kPa
22035C1Testethylenespherical burner56.9%stream200 kPa
22035D1Testethylenespherical burner45.6%stream200 kPa
22035D3Testethylenespherical burner45.5%stream200 kPa
22035F1Testethylenespherical burner36.5%stream200 kPa
22035G1Testethylenespherical burner29.1%stream200 kPa
22035G2Testethylenespherical burner85%stream201 kPa
22035J1Testethylenespherical burner85%stream50.6 kPa
22035J2Testethylenespherical burner85%stream51 kPa
22035J3Testethylenespherical burner85%stream51.4 kPa
22035J4Testethylenespherical burner85%stream51.4 kPa
22035J5Testethylenespherical burner85%stream51.6 kPa
22035J6Testethylenespherical burner85%stream51.7 kPa
22035J7Testethylenespherical burner85%stream51.9 kPa
19115A1Testethylenespherical burner20.7%103 kPa
19115D2Testethylenespherical burner20.6%103 kPa
19115B1Testethylenespherical burner20.6%103 kPa
19115B2Testethylenespherical burner20.5%103 kPa
19115F1Testethylenespherical burner20.4%103 kPa
19115G1Testethylenespherical burner20.4%103 kPa
19115K1Testethylenespherical burner20.3%103 kPa
19115L1Testethylenespherical burner20.3%103 kPa
19115N1Testethylenespherical burner20.2%103 kPa
19115M4Testethylenespherical burner20.1%103 kPa
19115Q1Testethylenespherical burner20.1%103 kPa
19123A1Testethylenespherical burner21%102 kPa
19123A2Testethylenespherical burner20.9%102 kPa
19123A3Testethylenespherical burner20.9%102 kPa
19123A4Testethylenespherical burner20.8%103 kPa
19123C1Testethylenespherical burner20.7%102 kPa
19123F1Testethylenespherical burner20.7%103 kPa
19123F2Testethylenespherical burner20.6%103 kPa
19123F3Testethylenespherical burner20.5%103 kPa
19123K1Testethylenespherical burner20.5%103 kPa
19123B1Testethylenespherical burner20.4%103 kPa
19123D1Testethylenespherical burner20.4%103 kPa
19123J1Testethylenespherical burner20.3%103 kPa
19123L1Testethylenespherical burner20.3%103 kPa
19123L2Testethylenespherical burner20.2%103 kPa
19123L3Testethylenespherical burner20.1%103 kPa
19123L4Testethylenespherical burner20.1%103 kPa
19123L5Testethylenespherical burner20%103 kPa
19123L6Testethylenespherical burner20%103 kPa
19123L7Testethylenespherical burner19.9%103 kPa
19137A1Testethylenespherical burner21%102 kPa
19137B1Testethylenespherical burner21%102 kPa
19137C1Testethylenespherical burner20.9%102 kPa
19137D1Testethylenespherical burner20.8%102 kPa
19137F1Testethylenespherical burner20.7%102 kPa
19137F2Testethylenespherical burner20.7%102 kPa
19137F3Testethylenespherical burner20.6%102 kPa
19137G1Testethylenespherical burner20.5%102 kPa
19137H1Testethylenespherical burner20.5%102 kPa
19137J1Testethylenespherical burner20.4%102 kPa
19137K1Testethylenespherical burner20.4%102 kPa
19137K2Testethylenespherical burner20.4%102 kPa
19137L1Testethylenespherical burner20.3%102 kPa
19137L2Testethylenespherical burner20.3%102 kPa
19137L3Testethylenespherical burner20.2%103 kPa
19137L4Testethylenespherical burner20.2%103 kPa
19137L5Testethylenespherical burner20.2%103 kPa
19137L6Testethylenespherical burner20.1%103 kPa
19137L7Testethylenespherical burner20.1%103 kPa
19137L8Testethylenespherical burner20%103 kPa
19142G1Testethylenespherical burner39.7%102 kPa
19142G2Testethylenespherical burner39%103 kPa
19142G3Testethylenespherical burner38.4%103 kPa
19142F1Testethylenespherical burner37.9%103 kPa
19142J2Testethylenespherical burner37.3%104 kPa
19142G4Testethylenespherical burner37.9%100 kPa
19142G5Testethylenespherical burner37.6%100 kPa
19142J3Testethylenespherical burner37.3%100 kPa
19150A1Testethylenespherical burner39.8%102 kPa
19150A3Testethylenespherical burner39.7%102 kPa
19150A4Testethylenespherical burner39.5%102 kPa
19150A5Testethylenespherical burner39.3%103 kPa
19150B2Testethylenespherical burner38.9%103 kPa
19150C1Testethylenespherical burner38.6%104 kPa
19150B3Testethylenespherical burner38.3%104 kPa
19150D2Testethylenespherical burner38%105 kPa
19150F1Testethylenespherical burner37.1%106 kPa
19150G2Testethylenespherical burner37%106 kPa
19150H1Testethylenespherical burner36.6%106 kPa
19150J1Testethylenespherical burner36.2%106 kPa
19150G3Testethylenespherical burner35.8%106 kPa
19150N1Testethylenespherical burner30%102 kPa
19150S1Testethylenespherical burner29.4%102 kPa
19156B2Testethylenespherical burner38.9%103 kPa
19156B4Testethylenespherical burner38.8%103 kPa
19156K1Testethylenespherical burner38%104 kPa
19156C1Testethylenespherical burner37.7%105 kPa
19156C2Testethylenespherical burner37.5%104 kPa
19156C3Testethylenespherical burner37.1%104 kPa
19156J1Testethylenespherical burner37.3%104 kPa
19156J2Testethylenespherical burner37%104 kPa
19156J3Testethylenespherical burner36.9%104 kPa
19156J4Testethylenespherical burner36.6%104 kPa
19156J5Testethylenespherical burner36.4%104 kPa
19156J6Testethylenespherical burner36.3%104 kPa
19156J7Testethylenespherical burner36.1%104 kPa
19171D1Testethylenespherical burner39.4%102 kPa
19171D2Testethylenespherical burner38.7%102 kPa
19171D3Testethylenespherical burner38.1%102 kPa
19171D4Testethylenespherical burner37.9%102 kPa
19171D5Testethylenespherical burner37.4%102 kPa
19171S1Testethylenespherical burner37%102 kPa
19171B1Testethylenespherical burner37.9%102 kPa
19171B3Testethylenespherical burner37.2%103 kPa
19171J1Testethylenespherical burner36.5%104 kPa
19171J2Testethylenespherical burner36.3%104 kPa
19171J3Testethylenespherical burner36.1%104 kPa
19171J4Testethylenespherical burner36%105 kPa
19175A2Testethylenespherical burner39.8%127 kPa
19175A3Testethylenespherical burner39.7%128 kPa
19175A4Testethylenespherical burner39.1%128 kPa
19175B1Testethylenespherical burner38.9%128 kPa
19175B4Testethylenespherical burner38.8%128 kPa
19175B5Testethylenespherical burner38.5%128 kPa
19175B6Testethylenespherical burner38.9%127 kPa
19175B7Testethylenespherical burner38.8%127 kPa
19175B8Testethylenespherical burner38.6%127 kPa
19175B9Testethylenespherical burner38.4%127 kPa
19175N1Testethylenespherical burner38.3%127 kPa
19175N2Testethylenespherical burner37.9%128 kPa
19175N3Testethylenespherical burner37.7%128 kPa
19182G1Testethylenespherical burner39.9%127 kPa
19182G2Testethylenespherical burner39.7%128 kPa
19182G3Testethylenespherical burner39.5%128 kPa
19182G6Testethylenespherical burner39.4%128 kPa
19182G7Testethylenespherical burner39.2%129 kPa
19182G8Testethylenespherical burner39%129 kPa
19182G9Testethylenespherical burner38.8%129 kPa
19182N1Testethylenespherical burner38.6%129 kPa
19182N2Testethylenespherical burner38.9%129 kPa
19182N3Testethylenespherical burner38.8%129 kPa
19182A1Testethylenespherical burner38.6%129 kPa
19182C1Testethylenespherical burner38.5%130 kPa
19182C2Testethylenespherical burner38.3%130 kPa
19182N4Testethylenespherical burner38%131 kPa
19182F1Testethylenespherical burner37.8%131 kPa
19189A1Testethylenespherical burner39.9%127 kPa
19189A2Testethylenespherical burner39.6%129 kPa
19189A3Testethylenespherical burner39.5%129 kPa
19189D1Testethylenespherical burner39.4%129 kPa
19189A4Testethylenespherical burner39.2%130 kPa
19189D2Testethylenespherical burner39.1%130 kPa
19189D3Testethylenespherical burner39%130 kPa
19189H1Testethylenespherical burner38.8%131 kPa
19189J1Testethylenespherical burner38.7%131 kPa
19189J2Testethylenespherical burner38.3%131 kPa
19189J3Testethylenespherical burner38%131 kPa
19189K1Testethylenespherical burner37.6%131 kPa
19189K2Testethylenespherical burner37.3%131 kPa
19189K3Testethylenespherical burner36.9%131 kPa
19189P1Testethylenespherical burner36.5%131 kPa
19196A1Testethylenespherical burner39.6%127 kPa
19196A2Testethylenespherical burner39.4%127 kPa
19196A3Testethylenespherical burner39.2%128 kPa
19196B1Testethylenespherical burner39.1%128 kPa
19196B2Testethylenespherical burner39%128 kPa
19196B3Testethylenespherical burner38.8%128 kPa
19196B4Testethylenespherical burner38.7%128 kPa
19196C1Testethylenespherical burner38.5%128 kPa
19196C2Testethylenespherical burner38.3%128 kPa
19196D1Testethylenespherical burner38.6%128 kPa
19196D2Testethylenespherical burner38.4%128 kPa
19196F1Testethylenespherical burner38.2%128 kPa
19196N1Testethylenespherical burner38.2%128 kPa
19200A1Testethylenespherical burner39.5%102 kPa
19200A2Testethylenespherical burner39.3%102 kPa
19200A3Testethylenespherical burner39.2%102 kPa
19200A4Testethylenespherical burner39.1%102 kPa
19200A5Testethylenespherical burner38.9%102 kPa
19200A6Testethylenespherical burner38.7%102 kPa
19200A7Testethylenespherical burner38.4%102 kPa
19200A8Testethylenespherical burner38.3%103 kPa
19200K1Testethylenespherical burner29.9%101 kPa
19200H1Testethylenespherical burner29.7%102 kPa
19200H2Testethylenespherical burner29.4%102 kPa
19200H3Testethylenespherical burner28.9%103 kPa
19206A1Testethylenespherical burner21%102 kPa
19206A5Testethylenespherical burner20.9%102 kPa
19206G1Testethylenespherical burner20.8%102 kPa
19206G2Testethylenespherical burner20.7%102 kPa
19206G3Testethylenespherical burner20.7%102 kPa
19206G4Testethylenespherical burner20.6%102 kPa
19206G5Testethylenespherical burner20.5%102 kPa
19206L2Testethylenespherical burner20.5%102 kPa
19206L3Testethylenespherical burner20.4%102 kPa
19206L4Testethylenespherical burner20.3%102 kPa
19206L6Testethylenespherical burner20.3%102 kPa
19206G7Testethylenespherical burner20.2%102 kPa
19206K1Testethylenespherical burner20.2%102 kPa
19206K2Testethylenespherical burner20.1%103 kPa
19206G8Testethylenespherical burner20.1%103 kPa
19206G9Testethylenespherical burner20%102 kPa
19206N1Testethylenespherical burner20%103 kPa
19206H1Testethylenespherical burner20%102 kPa
19206H2Testethylenespherical burner19.9%102 kPa
19206H3Testethylenespherical burner19.9%103 kPa
19206H4Testethylenespherical burner19.8%103 kPa
21301A1Testpropanespherical burner40%94.4 kPa
21301A2Testpropanespherical burner40%94.4 kPa
21301A3Testpropanespherical burner40%94.4 kPa
21301A4Testpropanespherical burner40%94.4 kPa
21301A5Testpropanespherical burner40%94.4 kPa
21301A6Testpropanespherical burner40%94.4 kPa
21301C1Testpropanespherical burner40%94.4 kPa
21301C2Testpropanespherical burner40%94.4 kPa
21301D1Testpropanespherical burner40%94.4 kPa
21301D2Testpropanespherical burner40%94.4 kPa
21301A7Testpropanespherical burner40%94.4 kPa
21301A8Testpropanespherical burner40%94.4 kPa
21301A9Testpropanespherical burner40%94.4 kPa
21301H1Testpropanespherical burner40%94.4 kPa
21301H2Testpropanespherical burner40%94.4 kPa
21301H3Testpropanespherical burner40%94.4 kPa
21301J1Testpropanespherical burner40%94.4 kPa
21301J2Testpropanespherical burner40%94.4 kPa
21301J3Testpropanespherical burner40%94.4 kPa
21301J4Testpropanespherical burner40%94.4 kPa
How the table was read, and what was repaired

Flame Design - inverse flames

PSI-10_Experimental table_Flame Design_Inverse Flame.csv

120 rows in the file, 120 kept as records.

sha256 97933ee9ae0b9ebc6b948a67485a0fe2f8218f753253a4f2be93c40d374c44e4 · fetched 2026-11-11

Flame Design - normal flames

PSI-10_Experimental table_Flame Design_Normal Flame.csv

207 rows in the file, 207 kept as records.

sha256 4a663292bd3f65201943cc71bd661a70383639276a9176f64105b285bf0b6deb · fetched 2026-11-11

NASA's description

Objectives

The primary objectives of this flight experiment are: A. Obtain soot-inception limits of quasi-steady normal and inverse spherical diffusion flames as functions of flow rate, Zst, amount of inert (N2 or CO2), and pressure for C2H4 and CH4 flames. Identify the corresponding temperatures in hot regions. Obtain similar limits and temperatures for inverse and normal coflow flames. B. Obtain detailed measurements in quasi-steady normal and inverse spherical diffusion flames for C2H4 and CH4. Determine the effects of flow rate, Zst, amount of N2, and pressure on flame temperature, size, color, and soot volume fraction. Evaluate the possible existence of steady flames. C. Obtain extinction limits as functions of Zst, amount of N2, and pressure for normal and inverse spherical C2H4 and CH4 flames. Identify the corresponding temperatures in hot regions. Identify the presence of radiative or kinetic extinction. Evaluate whether pseudo-flammability limits can be obtained for these flames.

Approach

Perform spherical diffusion flame tests in drop towers and aboard the International Space Station. Consider a broad range of reactant dilutions, flow rates and pressures for normal and inverse convection directions. Observe the flames with a broad suite of cameras, radiometers, photomultiplier tubes, and thermocouples.

Hypothesis

1. Soot formation requires a region where local C/O ratio and T exceed their critical values, and where strain rate is sufficiently low. 2. Microgravity spherical diffusion flames extinguish when the peak temperature first decreases below 1130 K. 3. Steady-state spherical diffusion flames are possible.

Research impacts and Earth benefits

This project has the potential for improving efficiency and reducing pollutant emissions in terrestrial combustors. For example, it is contributing to novel designs of future coal power plants.

Publications

33 listed in PSI, 33 with a DOI.

  1. The kinetics and warm flame chemistry associated with radiative extinction of spherical diffusion flamesWaddell Kendyl A., Irace Phillip H., Yablonsky Gregory, Constales Denis, Sunderland Peter B., Axelbaum Richard L.
  2. Soot Formation in Spherical Diffusion FlamesFrolov Sergey M., Ivanov Vladislav S., Frolov Fedor S., Vlasov Pavel A., Axelbaum Richard, Irace Phillip H., Yablonsky Grigoriy, Waddell Kendyl
  3. On the existence of steady-state gaseous microgravity spherical diffusion flames in the presence of radiation heat lossIrace Phillip H., Waddell Kendyl A., Constales Denis, Kim Minhyeng, Yablonsky Gregory, Sunderland Peter B., Axelbaum Richard L.
  4. Critical temperature and reactant mass flux for radiative extinction of ethylene microgravity spherical diffusion flames at 1 barIrace Phillip H., Waddell Kendyl A., Constales Denis, Sunderland Peter B., Axelbaum Richard L.
  5. An investigation of thermal radiation from laminar diffusion flames in a tri-coflow burner with central oxygenIrace P.H., Gopan A., Axelbaum R.L.
  6. SPHERICAL DIFFUSION FLAME IN MICROGRAVITY CONDITIONS: FIRST RESULTS OF JOINT RUSSIAN-AMERICAN SPACE EXPERIMENT FLAME DESIGN - ADAMANTundefined undefined, FROLOV S. M.
Show the other 27
  1. Observations of long duration microgravity spherical diffusion flames aboard the International Space StationIrace Phillip H., Lee Han Ju, Waddell Kendyl, Tan Logan, Stocker Dennis P., Sunderland Peter B., Axelbaum Richard L.
  2. Double blue zones in inverse and normal laminar jet diffusion flamesWang Zhengyang, Sunderland Peter B., Axelbaum Richard L.
  3. Dilution effects on laminar jet diffusion flame lengthsWang Zhengyang, Sunderland Peter B., Axelbaum Richard L.
  4. A new method of flame temperature measurement utilizing the acoustic emissions from laser-induced plasmasWu Wendong, Adeosun Adewale, Axelbaum Richard L.
  5. Structure and extinction of spherical burner-stabilized diffusion flames that are attached to the burner surfaceRodenhurst Melvin K., Chao Beei-Huan, Sunderland Peter B., Axelbaum Richard L.
  6. Effects of Inert Placement (Z st) on Soot and Radiative Heat Flux in Turbulent Diffusion FlamesGopan Akshay, Yang Zhiwei, Kumfer Benjamin M., Axelbaum Richard L.
  7. Observation of water–gas shift equilibrium in diffusion flamesWu Wendong, Yablonsky Gregory, Axelbaum Richard L.
  8. An Approach to Thermocouple Measurements That Reduces Uncertainties in High-Temperature EnvironmentsKrishnan Siddharth, Kumfer Benjamin M., Wu Wendong, Li Jichuan, Nehorai Arye, Axelbaum Richard L.
  9. Modeled quenching limits of spherical hydrogen diffusion flamesLecoustre V.R., Sunderland P.B., Chao B.H., Axelbaum R.L.
  10. Simplifying the complexity of diffusion flames through interpretation in C/O ratio spaceXia Fei, Axelbaum Richard L.
  11. Numerical study of flame structure and soot inception interpreted in carbon-to-oxygen atom ratio spaceXia Fei, Yablonsky Gregory S., Axelbaum Richard L.
  12. Stability of spray combustion for water/alcohols mixtures in oxygen-enriched airYi Fei, Axelbaum Richard L.
  13. Numerical investigation of spherical diffusion flames at their sooting limitsLecoustre V.R., Sunderland P.B., Chao B.H., Axelbaum R.L.
  14. Kinetic and radiative extinctions of spherical burner-stabilized diffusion flamesWang Q., Chao B.H.
  15. Extremely weak hydrogen flamesLecoustre V.R., Sunderland P.B., Chao B.H., Axelbaum R.L.
  16. Characteristics of non-premixed oxygen-enhanced combustion: II. Flame structure effects on soot precursor kinetics resulting in soot-free flamesSkeen S.A., Yablonsky G., Axelbaum R.L.
  17. Characteristics of non-premixed oxygen-enhanced combustion: I. The presence of appreciable oxygen at the location of maximum temperatureSkeen S.A., Yablonsky G., Axelbaum R.L.
  18. Soot inception limits in laminar diffusion flames with application to oxy–fuel combustionKumfer B.M., Skeen S.A., Axelbaum R.L.
  19. Radiative extinction of gaseous spherical diffusion flames in microgravitySANTA K, CHAO B, SUNDERLAND P, URBAN D, STOCKER D, AXELBAUM R
  20. Numerical and experimental observations of spherical diffusion flamesSanta K. J., Sun Z., Chao B. H., Sunderland P. B., Axelbaum R. L., Urban D. L., Stocker D. P.
  21. The effects of elevated pressure on the kinetics and extinction of hot, warm, and cool gaseous ethylene spherical diffusion flamesWaddell Kendyl A., Yablonsky Gregory, Constales Denis, Sunderland Peter B., Axelbaum Richard L.
  22. On Soot Inception in Nonpremixed Flames and the Effects of Flame StructureCHAO B. H., LIU S., AXELBAUM R. L.
  23. Measurement and analysis of soot inception limits of oxygen-enriched coflow flamesKumfer B.M., Skeen S.A., Chen R., Axelbaum R.L.
  24. Scalar dissipation rate at extinction and the effects of oxygen-enriched combustionChen R., Axelbaum R.L.
  25. A theoretical study on soot inception in spherical burner-stabilized diffusion flamesLiu S., Chao B.H., Axelbaum R.L.
  26. SOOTING LIMITS OF MICROGRAVITY SPHERICAL DIFFUSION FLAMES IN OXYGEN-ENRICHED AIR AND DILUTED FUELSUNDERLAND P. B., URBAN D. L., STOCKER D. P., CHAO B.-H., AXELBAUM∗ R. L.
  27. Effects of structure and hydrodynamics on the sooting behavior of spherical microgravity diffusion flamesSunderland P

Hardware and raw data

2.2 TB of raw data on PSI: reports 3, raw data 3,792, metadata 1, science documents 3, experimental table 2, engineering documents 1, representative image(s) 5. FlameLens reads the experimental table, not the raw video or sensor files.

On Earth

Cleaner combustion: Lower-soot, more efficient combustors and power plants.

“improving efficiency and reducing pollutant emissions in terrestrial combustors”