Seventh International Workshop on Microgravity Combustion and Chemically Reacting Systems
Sacksteder, Kurt
The Seventh International Workshop on Microgravity Combustion and Chemically Reacting Systems was planned for June 3-6, 2003, in Cleveland, Ohio, near the NASA John H. Glenn Research Center at Lewis Field. The new name for the workshop is based on the decision to broaden our scope to encompass support for future space exploration through basic and applied research in reacting systems that in some cases may not look like combustion. The workshop has been lengthened to 4 days with focus sessions on spacecraft fire safety and exploration-related research. We believe that the microgravity combustion science community is almost uniquely positioned to make substantial contributions to this new effort.
Test conditions.
Extracted from the paper by AI · “Verified” means a person checked it
| Fuel | O₂ | Pressure | Airflow | Sensors | Source | AI conf. | Status |
|---|---|---|---|---|---|---|---|
| PMMA cylinders |
— | — | — | — | p. 151 | 95% | Pending |
| JP8 droplets |
air and a mixture of oxygen and helium | — | — | diameter measurements | p. 127 | 90% | Pending |
| n-nonane droplets |
air and a mixture of oxygen and helium | — | — | diameter measurements | p. 127 | 90% | Pending |
| porous stainless-steel sphere burner fuel spherical flames |
— | 0.98 bar | quiescent | imaging | p. 64 | 95% | Pending |
Findings.
-
01
Oscillations in diffusion flames occur when at least one of the two Lewis numbers (fuel or oxidizer) is larger than one, specifically in mixtures deficient in the less mobile reactant.
Other · p. 39 · AI confidence 90% · Reported · Pending
“Oscillations would therefore occur in mixtures that are deficient in the less mobile reactant, namely in lean hydrocarbon-air or rich hydrogen-air mixtures.”
-
02
Instabilities in nominally planar diffusion flames occur only when there is sufficient reactant leakage through the reaction zone, typically at high flow rates or near-extinction conditions.
Other · p. 39 · AI confidence 90% · Reported · Pending
“A stability theory of a nominally planar flame shows that instabilities occur only when there is sufficient reactant leakage through the reaction zone.”
-
03
Soot appears inside the flame sheet for normal flames and outside the flame sheet for inverse flames in microgravity spherical diffusion flames.
Other · p. 64 · AI confidence 95% · Reported · Pending
“Note that soot, when present, appears inside the flame sheet for normal flames and outside for inverse flames.”
-
04
A transitional flow velocity exists above which an originally uniform spreading flame pulsates due to gas-phase recirculation cells caused by forced opposed flow, buoyancy, and thermocapillary effects.
Other · p. 95 · AI confidence 90% · Reported · Pending
“A transitional flow velocity was found above which an originally uniform spreading flame pulsates.”
-
05
Extinction of low stretch diffusion flames over solid fuel occurs when ongoing heat losses represent 80% or more of the flame feedback.
Suppression · p. 151 · AI confidence 95% · Reported · Pending
“extinction is observed when these losses represent 80% or more of the flame feedback.”
-
06
NASA specifications require an Upward Flame Propagation Test and a Heat and Visible Smoke Release Rates Test to assess material flammability in space vehicles.
Prevention · p. 219 · AI confidence 95% · Reported · Pending
“This document specifies two tests that need to be performed before a material is qualified to be used in a space vehicle, the “Upward Flame Propagation Test” (Test 1) and the “Heat and Visible Smoke Release Ra tes Test” (Test 2).”
-
07
Wavelength modulation spectroscopy (WMS) using diode lasers is an important method for quantitative species detection in microgravity-based measurements.
Detection · p. 254 · AI confidence 90% · Reported · Pending
“This work has helped to establish wavelength modulation spectroscopy (WMS) as an important method for species detection within the restrictions of microgravity-based measurements.”