Optical Particle Sizing For Hydrodynamics: Further Results

J. B. Riley; Y. C. Agrawal

doi:10.1117/12.964229

Translator Disclaimer

7 August 1986 Optical Particle Sizing For Hydrodynamics: Further Results

J. B. Riley, Y. C. Agrawal

Author Affiliations +

Proceedings Volume 0637, Ocean Optics VIII; (1986) https://doi.org/10.1117/12.964229
Event: 1986 Technical Symposium Southeast, 1986, Orlando, United States

Abstract

An Optical method for instantaneous measurement of suspended particle size distribution shows promise for the study of boundary layer dynamics in the ocean, where suspended particles affect boundary layer flow through stratification. The method is based on observing the an-gular distribution of scattered light from a sample, and inversion to produce the suspended particle size distribution, n(x). In a previous paper, an analytic inversion based on the Fraunhoffer approximation was examined. The function 0³I(0) was found approximately to be related by a Fourier transform to xn(x), with the result that elementary signal processing concepts apply. In this work, the issues of uniqueness and stabilty of the inversion are considered. Instability of inversion for small particles is observed, and has the result that while matrix inversion algorithms show promise, those which manipulate small eigenvalues distort inversions for small sizes. Uniqueness in terms of sampling is revisited, yielding a refined Nyquist sampling criterion. The validity of these results, derived from approximate diffraction theory, is demonstrated for "exact" Mie theory.

Citation Download Citation

J. B. Riley and Y. C. Agrawal "Optical Particle Sizing For Hydrodynamics: Further Results", Proc. SPIE 0637, Ocean Optics VIII, (7 August 1986); https://doi.org/10.1117/12.964229

ACCESS THE FULL ARTICLE