title: Assessment of refractive index gradients by standard rainbow thermometry.
abstract: Up to now the application of rainbow thermometry has been limited to particle systems possessing a uniform refractive index. This is mostly due to the absence of an appropriate data inversion algorithm that takes into account the presence of a refractive index gradient. In this paper, for the first time to our knowledge, exploiting a generalization of the Airy theory, a data inversion algorithm for a single droplet, presenting a parabolic refractive index gradient, is proposed. This data inversion algorithm is used to compute the diameter and the refractive index at the core and at the surface of a simulated burning droplet. The results are compared to the analytical solutions showing a satisfactory agreement.
authors.affiliation: Von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640, Rhode Saint Genèse, Belgium. vetrano@vki.ac.be
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Vetrano
authors.forename: Jeronimus Petrus Antonius Johannes
authors.initials: JP
authors.lastname: van Beeck
authors.forename: Michel Léon
authors.initials: ML
authors.lastname: Riethmuller