2. Materials and Methods
2.1. Experimental Setup
2.2. ADV Measurements and Analysis
3. Results and Discussion
3.1. Mean Flow Characteristics
3.2. Turbulent Flow Characteristics
3.3. Near-Bed Shear Stress
- The analysis of vertical profiles of streamwise normalized velocity revealed that the rate of flow development downstream was faster than that midstream. The midstream profiles were influenced by the downstream cylinder in all scenarios.
- The flow recirculation zones midstream (x/D~1.50–1.80) were larger and stronger than those downstream (x/D~0.90–1.30). The longest recirculation zone in S1 midstream was affected by the downstream cylinder, and there was zero interruption from the downstream cylinder in S2 and S3.
- The length of the recirculation zone increased with the increase in c/c spacing of cylinders. The rate of flow development to achieve cross-sectional mean velocity became slower with increasing c/c spacing.
- The maximum turbulent kinetic energy for all three scenarios occurred approximately near the end of their respective recirculation zones. The midstream ke had a significant influence on the ke in downstream.
- The variation of resultant Reynolds shear stress was relatively chaotic as compared to the turbulent kinetic energy. The maximum shear stresses occurred within the recirculation zone for all scenarios.
- The peaks of dimensionless maximum near-bed shear stress () were higher (5–20%) and occurred over an extended length of about 0.5D in midstream as compared to the peaks of downstream, which occurred over a short length of 0.2D. The highest value of in the TKE method was about 50% and 70% higher than that in the Reynolds and modified TKE methods, respectively.
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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|Experimental Scenarios||Cylinder Diameter (D)||Cylinder Spacing *||Flow Rate||Approach Water Depth (H)||Approach Flow Velocity θ||Reynolds Number Ϯ (Rd)||Shear Velocity ± (u *)||Average||Average||Data Retained|
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