We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Temporal modulation of turbulence structure over progressive erosion boundary under influence of wave current combined flow.
- Authors
Hansda, Sunil; Das, Vikas Kumar; Debnath, Koustuv
- Abstract
The action of wave dominated flow on river bank leads to retreatment of the bankline thereby causing intense erosion issues. The understanding of the bank erosion process mechanisms is of great importance in the context of protecting or controlling the progressive growth of bankline which imposes a direct threat on near bank fertile agricultural land and habitats. The present study emphasizes on acquiring improved understanding on the bank erosion processes related to wave action that severely impact the bank erosion rate. Turbulent fluctuations of the near bank flow were observed to be modulated due to the interplay between eroded bank wall and stream flow under the influence of wave following and against the current. The fluctuating turbulent velocity field was measured using micro acoustic Doppler velocimeter (ADV) at regions close to the bank wall during the different stages of the erosion progress. Streamwise turbulence intensity was found to be relatively large upto a particular undercut depth during the erosion progression. The integral time and length scales and Taylor microscales were determined for different temporal stages using autocorrelation function. Results depict that wave current combined flow in conjunction with rough wall surface formed by the erosion process amplifies the turbulent kinetic energy and turbulent dissipation rate at vicinity of the wall. The velocity fluctuations show large intermittency as evaluated from Gaussian pdf for wave current combined flows. This may affect the near wall turbulence structures which is a causative factor for enhancement of erosion rate as compared to current only flow. Article highlights: Modulation of turbulence scales under wave current combined flow. Interaction between wave current combined flow and roughness formed in bank wall due to erosion. Turbulent structures and its effects on progressive bank erosion process.
- Subjects
EROSION; TURBULENCE; STREAMFLOW; RIPARIAN areas; KINETIC energy; ACOUSTIC streaming
- Publication
Environmental Fluid Mechanics, 2022, Vol 22, Issue 4, p683
- ISSN
1567-7419
- Publication type
Article
- DOI
10.1007/s10652-022-09846-5