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Title: Experimental Investigation of Slowly Propagating Flames in Microgravity
Accurate measurements of the laminar flame speed are useful to constrain the uncertainty of chemical models. However, for slowly propagating flames, buoyancy distorts the flame and measuring flame speeds accurately becomes challenging. This is relevant for novel hydrofluorocarbon refrigerants, preventing an accurate assessment of their flammability. Additionally, nitrogenated chemistry could be investigated by measurements of ammonia/air flames but the low laminar flame speeds also lead to similar issues. The only way to circumvent buoyancy-induced effects is to gather measurements in microgravity. In this study, an image processing technique was developed to accurately extract the radius of the spherical flame. This is required as the projection of a sphere on a plane leads to measurement error. A lab-scale drop tower was designed and built to achieve approximately 500 ms of free fall time. The direct imaging technique was combined with the drop tower to gather flame measurements in free fall. The methodology was applied to obtain the laminar flame speed of a lean, high-pressure methane/air flame.  more » « less
Award ID(s):
2053239
PAR ID:
10504157
Author(s) / Creator(s):
;
Publisher / Repository:
Spring Techical Meeting of the Eastern States Section of the Combustion Institute
Date Published:
Journal Name:
Spring Techical Meeting of the Eastern States Section of the Combustion Institute
Subject(s) / Keyword(s):
Spherical Flame Microgravity Buoyancy Laminar Flames
Format(s):
Medium: X
Location:
Athens, Georgia
Sponsoring Org:
National Science Foundation
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