Characteristic of Vertical Reynolds Shear Stress in a Patchy Heterogeneous Open Channel
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In turbulent flow, the Reynolds stress provides an understanding of the shear dispersion within the flow. Turbulence can be said to have an effect equivalent to the Reynolds shear stresses and are indicators of turbulence transport. This paper examined the characteristic of vertical Reynolds Shear stress in a patchy heterogeneous open channel using two experimental conditions for flexible and rigid vegetation interaction with gravel bed. The results show the value of vertical Reynolds stress decreases downstream along the channel section and as the distance from change in roughness increases. This is attributed to the effects of the bed roughness configuration (due to the preceding vegetated bed roughness) on the vertical Reynolds stress distribution. However, the position of maximum vertical Reynolds stress is located near bed over the vegetated zone. This provides an indication that the vegetated bed serves as the primary source of turbulence for the flow.
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