Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
TURBULENT FLOW OVER DUNES: EXPERIMENTAL DETERMINATION
Submission Author:
Jimmy Alvarez , SP
Co-Authors:
Jimmy Alvarez, Willian Righi Assis, Erick de Moraes Franklin
Presenter: Jimmy Alvarez
doi://10.26678/ABCM.ENCIT2022.CIT22-0276
Abstract
Sand dunes are frequently found in both nature and industry. Barchans are a type of dunes characterized by the presence of two tips pointing downstream in the direction of the fluid flow. These dunes appear mainly under unidirectional flows and with limited sediment supply. In natural environments barchan dunes are found in deserts and river beds, and in industrial applications they can appear in petroleum pipelines, causing pressure drops and flow’s obstruction. The presence of the dune perturbs the fluid,and some turbulent flow features aren’t fully understood. In this configuration, strong perturbations are observed in the fluid flow, with the wake of the upstream barchan interacting with the downstream dune. In this experimental investigation, heaps of glass beads were placed in a rectangular channel made of transparent material and were entrained by a turbulent water flow, forming two barchan dunes that interacted with each other. The fluid flow was characterized by two-dimensional particle image velocimetry (2D-PIV). We report results for two cases: (i) empty channel, and (ii) with barchans inside the channel. Mean and fluctuation fields were obtained, and the velocities and stresses computed.
Keywords
granular bed, barchan dunes, Turbulent flow, PIV
