Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
ASYMMETRIES IN LIQUID FILM THICKNESS IN HORIZONTAL AIR-WATER ANNULAR FLOW
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.COBEM2019.COB2019-1779
Abstract
Two-phase annular flow has numerous industrial applications. During this flow pattern, liquid flows alongside the wall forming a thin film, that influences several other parameter as heat transfer and pressure drop. The measurement and modeling of this liquid film is difficult, as the film is very thin and asymmetric. Also, the film thickness is time-dependent due to wave-formation. Earlier measurement techniques used invasive methods with high uncertainty, unsuitable for microscale applications. New, non-invasive techniques are developed, however experimental error continues an issue. This paper aims to provide an overview on liquid film asymmetries on horizontal air-water annular flow. For that, a database of 102 liquid film thickness profile was compiled from 9 experimental studies. The asymmetries parameters t_a/t_b and t_t/t_b were evaluated against four predictive methods. Results points that the t_a/t_b is a better parameter, and also that the film asymmetry correlates well with the Froude number. The correlations tested can only predict with +- 50 %, mainly due to measurement error.
Keywords
Two-phase Flow, liquid film thickness, air-water, Annular flow
