Recent advances and applications of digital holography in multiphase reactive/nonreactive flows: a review

Abstract

In various multiphase flows, the characterization of particle dynamics is of great significance to understand the interaction between particles and the surrounding flows. Digital holography (DH) is a versatile 3D imaging technique, which has shown great advantages in quantitative analysis and non-intrusive diagnosis of various particle fields. This review focuses on the advances and applications of DH in multiphase reactive/non-reactive flows in the last two decades. The basic principles of DH are introduced firstly, including its mathematical background and representative experimental configurations. Then, the image processing algorithms for hologram reconstruction and automatic focusing are summarized, along with the methods for separating overlapping particles and tracking moving particles. As a prevailing and powerful tool, the recent applications of deep learning in processing holographic images is also included in this review. Furthermore, the applications of DH in the characterization of particle dynamics in multiphase reactive/non-reactive flows are surveyed in detail. Lastly, the review concludes with the discussion of the technical limits of DH and provides insights into its promising future research directions.

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