Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Classification of flow patterns in air-water flows using confocal chromatic microscopy
Submission Author:
Fernando Neves Quintino dos Santos , SP , Brazil
Co-Authors:
Fernando Neves Quintino dos Santos, Cristiano Tibiriçá
Presenter: Fernando Neves Quintino dos Santos
doi://10.26678/ABCM.COBEM2023.COB2023-1475
Abstract
Two phase-flow has several applications, including but not limited to refrigeration or power generation. Several factor influences the flow, such as flow pattern, tube geometry, velocity, and other. One important parameter is the flow pattern, as it has a close relationship in the behavior of important parameters such as pressure drop, and phase dispositions. Flow patterns can be divided into two main categories: dispersed and separated flows. Despite its importance, this classification is subjective, as there is no consolidated objective method for classification. This paper proposes the use of a novel optical technique called chromatic confocal microscopy to classify flow patterns. It works measuring the wavelength of focal reflections happening in the interfaces (eg. glass-liquid or liquid-glass). As there is a significant difference in the liquid-gas interfaces in the flow patterns, the sensor output signal can be used for flow classification. Advantages of the technique are that it has a high measurement rate, is non-intrusive, and can measure distance, which can be used to measure liquid thickness and waves. Experiments were conducted in a air-water horizontal flow, in a 8 mm squared tube, using a confocal chromatic microscope to evaluate liquid thickness. Results point that the technique is adequate for intermittent flows.
Keywords
multiphase flow, Flow patterns, air-water, confocal chromatic microscopy
