A Comprehensive Picture for Binary Interactions of Subaqueous Barchans

Autor(es)

Assis, W. R. ^[1] ; Franklin, E. M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Sch Mech Engn, Campinas - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Geophysical Research Letters; v. 47, n. 18 SEP 28 2020.
• Citações Web of Science: 1

Resumo

We investigate experimentally the short-range interactions occurring between two subaqueous barchans. The experiments were conducted in a water channel of transparent material where controlled grains were poured inside, and a camera placed on the top acquired images of the bedforms. We varied the grain types (diameter, density, and roundness), pile masses, transverse distances, water flow rates, and initial conditions. As a result, five different patterns were identified for both aligned and off-centered configurations, and we propose interaction maps that depend basically on the ratio between the number of grains of each dune, Shields number, and alignment of barchans. In addition, we show experimental indications that an ejected barchan has roughly the same mass of the impacting one in some cases and that in wake-dominated processes the asymmetry of the downstream dune is large. The present results shed light on the size regulation of barchans found on Earth and other planets. (AU)

• Processo FAPESP: 19/10239-7 - Instabilidades em leitos móveis: dinâmica granular e interação com o escoamento
• Beneficiário: Willian Righi Assis
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 18/14981-7 - Modelagem de escoamentos granulares densos: experimentos, simulações numéricas e análises de estabilidade
• Beneficiário: Erick de Moraes Franklin
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores - Fase 2