Quantitative Rainbow Schlieren Deflectometry as a Temperature Diagnostic for Spherical Flames

National Aeronautics and Space Administration, Glenn Research Center at Lewis Field, Cleveland, Ohio 44135, USA.
Applied Optics (Impact Factor: 1.78). 08/2006; 45(20):4826-32. DOI: 10.1364/AO.45.004826
Source: NTRS


Numerical analysis and experimental results are presented to define a method for quantitatively measuring the temperature distribution of a spherical diffusion flame using rainbow schlieren deflectometry in microgravity. The method employed illustrates the necessary steps for the preliminary design of a rainbow schlieren system. The largest deflection for the normal gravity flame considered in this paper is 7.4 x 10(-4) rad, which can be accurately measured with 2 m focal-length collimating and decollimating optics. The experimental uncertainty of deflection is less than 5 x 10-(5) rad.

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    • "Optical computerized tomography (OCT) has become the first chosen method for the real-time visualization and diagnosis of the transient state measurement for various flow fields [1] [2] [3], especially flame flow fields [4] [5] [6] [7] [8] [9] [10] [11]. In principle, all current OCT methods work out the 3-D density distribution for flow fields by the Gladstone-Dale (G-D) equation, on the basis of the refractive index has been reconstructed from the experimental fringes information. "
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