Seminar Title:
Conference Return Seminar: Flow Pattern and Vegetation Interactions in a Straight Channel; An Experimental Investigation
Seminar Type:
Departmental Seminar
Department:
Civil Engineering
Speaker Name:
Pritam Kumar (521ce1010)
Speaker Type:
Student
Venue:
Seminar hall, Department of Civil Engineering
Date and Time:
23 Sep 2024 2:30 PM
Contact:
M. GATTU
Abstract:
The presence of natural vegetation in a river or canal can have various effects on different aspects of flow structures, including conveyance capacity, turbulent properties, sediment transportation and deposition, pollutant transportation, water quality improvement, and the provision of food and shelter for aquatic life. The focus of the present study is on the turbulent flow structure in a partially vegetated straight channel. Experimental work was car-ried out in a straight tilting flume measuring 12 meters in length, 0.6 meters in width, and 0.9 meters in depth. In this study, natural Vetiver grass (Chrysopogon zizanioides) was used in the half width of the channel and placed in a staggered pattern on the sand bed under emergent conditions. The experiment involved the use of natural flexible vegetation in the emergent condition on one side of the channel under mobile bed conditions to in-vestigate turbulent flow properties, including three-dimensional velocity, three-dimensional turbulent intensity, and turbulent kinetic energy. Instantaneous velocities were recorded using a 3-D micro ADV with a 5 cm down-looking sensor operating at 50 Hz to analyze the time-averaged velocity and turbulence properties under steady flow condi-tions. The turbulent flow properties were examined in the vegetated side, interface of veg-etation, and non-vegetated side, and comparisons were made between these regions. The experimental results revealed that longitudinal velocity increases in the non-vegetated side while decreasing in the vegetated side and S-shape profile is observed at the interface of the vegetation in the channel. The distribution of vertical velocity decreases in the non-vegetated side, increases in the interface of vegetation, and further increases in the vege-tated side of the channel. Three-dimensional turbulent intensity and turbulent kinetic en-ergy are also discussed in this study. This study provides valuable insights into under-standing the flow characteristics in the non-vegetated, interface, and vegetated side of the channel.