Abstract
A low-gravity environment offers advantages to investigations concerned with soot growth or flame radiation by eliminating of buoyancy-induced convection. Basic to each type of study is knowledge of spatially resolved soot volume fraction (fv). Laser-induced incandescence (LII) has emerged as a diagnostic for soot volume fraction determination because it possesses high temporal and spatial resolution, geometric rersatility and high sensitivity. Implementation and system characterization of LII in a drop tower that provides 2.2 s of low-gravity (μg) at the NASA Lewis Research Center are described here. Validation of LII for soot volume fraction determination in μg is performed by comparison between soot volume fraction measurements obtained by light extinction and LII in low-gravity for laminar gas-jet diffusion flames consisting of a 50/50-mixture (by volume) of acetylene/nitrogen issuing into quiescent air. Quantitative soot volume fraction measurements within other laminar flames of ethane and propane and a turbulent diffusion flame in μg via LII are also demonstrated. An analysis of LII images of a turbulent acetylene diffusion flame at I g and μg is presented.
Original language | English (US) |
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Pages (from-to) | 66-74 |
Number of pages | 9 |
Journal | Microgravity Science and Technology |
Volume | 10 |
Issue number | 2 |
State | Published - 1997 |
All Science Journal Classification (ASJC) codes
- Modeling and Simulation
- General Engineering
- General Physics and Astronomy
- Applied Mathematics