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Analysis of the Sampling Behavior of a Phase Doppler Interferometer
Published
Author(s)
J F. Widmann, S R. Charagundla, Cary Presser, Grace L. Yang, Stefan D. Leigh
Abstract
A phase Doppler interferometer (PDI) was used to measure the intensity (i.e., the expected number of droplets measured per unit time) of a swirling methanol spray flame. Gaps observed in the data, which have been previously reported (McDonell and Samuelsen, 1955), correspond to periods where the PDI was inactive. The intensity of the spray as a function of position within the flame was determined from the distribution of interarrival times (time between subsequent droplets entering the probe volume of the PDI), and a statistical simulation was developed to correct for the regularly occurring intervals in which the PDI does not accept data. The duration of this dead time was determined to be difference} 5.2 ms for all points in the flame for which data were collected. A statistical model is presented to correct for the observed behavior of the PDI, and the good agreement between the simulations and the experimental data indicate that the spray can be adequately modeled by Poisson statistics.
Widmann, J.
, Charagundla, S.
, Presser, C.
, Yang, G.
and Leigh, S.
(1999),
Analysis of the Sampling Behavior of a Phase Doppler Interferometer, 37th AIAA Aerospace Sciences Meeting and Exhibit, Undefined
(Accessed October 17, 2025)