112. An improved size and refractive index measurement of a pentadecane single droplet in a heated chamber
W. Manosroi1, N. Roth2, B. Weigand3
1, 2, 3Institute of Aerospace Thermodynamics, University of Stuttgart, Pfaffenwaldring 31, 70569, Germany
1Department of Mechanical Engineering, Chiang Mai University, Chiang Mai 50200, Thailand
E-mail: email@example.com, firstname.lastname@example.org, email@example.com‑stuttgart.de
Abstract. The pentadecane single droplet size of less than 20 µm and its refractive index were measured at various ambient temperatures of 100, 120, 150 and 180 °C. The experimental setup was equipped with the high speed linear CCD camera to give sharp and clearly visible MDRs (Morphology Dependent Resonances) structure from the droplet refractive index. The valve of the heated chamber was closed during the experiment until the droplet disappeared from the chamber to increase the measurement time of about 2 folds in order to obtain more experimental data of the droplet behaviors. The cooling device was mounted on the heated chamber to improve boundary condition and smooth the ambient temperature. The obtained droplet sizes were in good agreement with both the D2 law and the Rapid Mixing Model (RMM), while the measured droplet refractive index values were closed to those calculated from the previous reported formula. This has indicated the reliability and applicability of this improved measurement technique for a better understanding of the real fuel droplet behaviors in a combustion system.
Keywords: droplet, ambient temperatures, diameter, refractive index, morphology dependent resonances.
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Cite this article
Manosroi W., Roth N., Weigand B. An improved size and refractive index measurement of a pentadecane single droplet in a heated chamber. Journal of Measurements in Engineering, Vol. 5, Issue 1, 2017, p. 1‑10.
Journal of Measurements in Engineering. March 2017, Volume 5, Issue 1
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