Space evolution of turbulent structures over a flexible vegetation area
Por:
Jonathan Pastrana, Edwin, Aguilar-Chavez, Ariosto, Mendoza-Gonzalez, Angel
Publicada:
1 mar 2023
Resumen:
In a natural or artificial channel, the presence of vegetation at the
bottom and on the wall is usual. The effects produced by the presence of
this is an alteration of the flow field. The magnitude of the changes in
the flow field depends on the extension, height, density, and
flexibility of the vegetation. To analyze the turbulent structures in
detail in this work, an experimental study was carried out in a
laboratory, in a rectangular channel with a section of submerged,
flexible and artificial vegetation. The measurement region was located
upstream of the vegetation zone until the end of it, in addition, the
asymmetry that the presence of the channel wall can induce was
determined. The measurements were performed with an Acoustic Doppler
Velocimeter (ADV) instrument. The results allow to identify the
development of the mixing layer from the average velocity patterns and
the Reynolds stress. In the case of the average velocity profiles over
the vegetation layer, it was possible to identify an inflection point
where Kelvin-Helmholtz instabilities type were identified. In order to
analyze the processes in the mixing layer, a phenomenological model is
proposed based on the analysis of the curvature of the averaged
velocities. In addition, the contribution to the moment transport rate
by the identified turbulent structures were determined with a quadrant
analysis of fluctuating velocities.
Filiaciones:
Jonathan Pastrana, Edwin:
Univ Nacl Autonoma Mexico, Ciudad De Mexico, Mexico
Aguilar-Chavez, Ariosto:
Inst Mexicano Tecnol Agua, Jiutepec, Mexico
Mendoza-Gonzalez, Angel:
Univ Nacl Autonoma Mexico, Ciudad De Mexico, Mexico
gold, All Open Access; Gold
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