Evaluation of the extinction factor in a laminar flame established over a PMMA plate in microgravity

A methodology for estimating the extinction factor at λ=530 nm in diffusion flames is presented. All experiments have been in microgravity and have as their objective the production of quantitative data that can serve to evaluate the soot volume fraction. A better understanding of soot formation and radiative heat transfer is of extreme importance to many practical combustion related processes such as spacecraft fire safety. The experimental methodology implements non-axisymmetric configurations that provide a laminar diffusion flame at atmospheric pressure. PMMA is used as fuel. The oxidizer flows parallel to its surface. Optical measurements are performed at the 4.74 s ZARM drop tower.

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