Revista
Recursos Hídricos
DOI:10.5894/rh42n1-cti12
Este artigo é parte integrante da Revista Recursos Hídricos, Vol. 42, Nº 1, 113-120, março de 2021.
Influência da vegetação nas transferências de quantidade de movimento laterais
Influence of vegetation on lateral momentum transfers
Cátia TABORDA1, Cristina FAEL1, César SANTOS1, Ana RICARDO2, Rui FERREIRA3
1 Universidade de Beira Interior - CMADE, Rua Marquês D’Avila e Bolama, 6201-001 Covilhã, csbt@ubi.pt, cmsf@ubi.pt, a34474@ubi.pt
2 CERIS, Avenida Rovisco Pais 1, 1049-003 Lisboa, ana.ricardo@tecnico.ulisboa.pt (Associado)
3 CERIS - Instituto Superior Técnico, Avenida Rovisco Pais 1, 1049-001 Lisboa, ruimferreira@tecnico.ulisboa.pt (Associado)
RESUMO
Nesta comunicação analisam-se os resultados experimentais obtidos num canal parcialmente vegetado, constituído por um corredor de matriz escalonada emergente rígida, visando estudar a influência da vegetação nas transferências laterais de massa e quantidade de movimento. É ainda quantificada a espessura da camada de mistura, através de modelos teóricos, dado que desempenha um papel significativo nessas transferências. A análise é complementada com o estudo da presença das estruturas coerentes de larga escala que promovem a transferência de massa e de quantidade de movimento através do escoamento turbulento que ocorre entre o canal central e o corredor vegetado.
Palavras-chave: canal parcialmente vegetado; vegetação emersa rígida; interface; transferências laterais.
ABSTRACT
In this paper, the experimental results obtained in a partially vegetated channel, consisting of an area with emergent and rigid stems in a staggered pattern, are analyzed in order to study the influence of vegetation on the lateral mass and momentum transfers. The mixing layer width is also quantified, using theoretical models, as it plays a significant role in these transfers. The analysis is complemented with the study of the presence of coherent large-scale structures that promote the mass and momentum transfers through the turbulent flow that occurs between the central channel and the vegetated area.
Keywords: partially vegetated channel; rigid emergent vegetation; interface; lateral transfers.
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