ï»¿ï»¿**Article details**

**Title: **Rotational Vortex Rope Detection using Recurrence Plot Analysis

**Author(s): ***Angela Digulescu* *Teodor Petruţ* *Ion Candel* *Cornel Ioana* *Florentina Bunea* *Georgiana Dunca* *Diana-Maria Bucur* *Alexandru ÅžerbÄƒnescu*

**Abstract: **In this paper, a new approach is proposed for the assessment of a vortex in fluid flow using an active acoustic system. The experiment is done on a reduced scale experimental pipe with ultrasonic transceivers. The purpose of the paper is to point out the presence of cavitation appearing in this pipe using wide band signals in the active acoustic system mode. Therefore, the Recurrence Plot Analysis (RPA) method which constitutes an interesting tool for the characterization of a dynamical system is used in terms of signal processing. The investigation is done varying the flow from steady flow to cavitation flow and backwards.

**Keywords: **non-intrusive monitoring, recurrence plot analysis, phase space.

** References: **

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