# A Comparative Study between Sand- and Gravel-Bed Open Channel Flows in the Wake Region of a Bed-Mounted Horizontal Cylinder

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## Abstract

**:**

## 1. Introduction

## 2. Experimental Details

#### 2.1. Experimental Instrumentations

#### 2.2. Bed Settings

#### 2.3. Experimental Conditions and Measuring Stations

#### 2.4. ADV System and Data Collection Procedure

## 3. Results and Discussion

#### 3.1. Mean Velocities

#### 3.2. Reynolds Normal Stress (RNS) Distribution

#### 3.3. Reynolds Shear Stress (RSS)

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 4.**Particle size distribution curve for (

**a**) the sand-bed (Run 1 and Run 2) and (

**b**) the gravel-bed material (GB 1).

**Figure 5.**Schematic of different regions of flow field upstream and downstream of a circular cylinder.

**Figure 6.**The vertical profiles of normalized time-averaged longitudinal velocity ($\overline{u}/{U}_{max}$) at different measuring stations ($x$) for Run 1, Run 2, and GB 1.

**Figure 7.**The variation of normalized time-averaged vertical velocity ($\overline{w}/{U}_{max}$) against normalized vertical distance ($\overline{z}$) at different measuring stations ($x$) for Run 1, Run 2, and GB 1.

**Figure 8.**The vertical profiles of normalized longitudinal RNS (${\sigma}_{uu}/{{U}_{max}}^{2}$) at different measuring stations ($x$) for Run 1, Run 2, and GB 1.

**Figure 9.**The variation of normalized time-averaged vertical RNS (${\sigma}_{ww}/{{U}_{max}}^{2}$) against normalized vertical distance ($\overline{z}$) at different measuring stations ($x$) for Run 1, Run 2, and GB 1.

**Figure 10.**The vertical profiles of normalized RSS (${\tau}_{uw}/{{U}_{max}}^{2}$) at different measuring stations ($x$) for Run 1, Run 2, and GB 1.

Exp. Run | D (m) | ${\mathit{S}}_{0}(\%)$ | $\mathit{h}$ (m) | $\mathit{U}$ (m/s) | $\mathit{A}\mathit{r}$ | ${\mathit{d}}_{50}\left(\mathbf{m}\right)$ | $\mathit{R}\mathit{e}$ | $\mathit{R}{\mathit{e}}_{*}$ | $\mathit{F}\mathit{r}$ |
---|---|---|---|---|---|---|---|---|---|

Run 1 | 0.05 | 0.023 | 0.30 | 0.15 | 3.1 | 0.00254 | 45,000 | 18.03 | 0.09 |

Run 2 | 0.05 | 0.023 | 0.30 | 0.19 | 3.1 | 0.00254 | 57,000 | 23.37 | 0.11 |

GB 1 | 0.06 | 0.022 | 0.25 | 0.25 | 2.4 | 0.04200 | 62,500 | 1050 | 0.16 |

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**MDPI and ACS Style**

Devi, K.; Hanmaiahgari, P.R.; Balachandar, R.; Pu, J.H.
A Comparative Study between Sand- and Gravel-Bed Open Channel Flows in the Wake Region of a Bed-Mounted Horizontal Cylinder. *Fluids* **2021**, *6*, 239.
https://doi.org/10.3390/fluids6070239

**AMA Style**

Devi K, Hanmaiahgari PR, Balachandar R, Pu JH.
A Comparative Study between Sand- and Gravel-Bed Open Channel Flows in the Wake Region of a Bed-Mounted Horizontal Cylinder. *Fluids*. 2021; 6(7):239.
https://doi.org/10.3390/fluids6070239

**Chicago/Turabian Style**

Devi, Kalpana, Prashanth Reddy Hanmaiahgari, Ram Balachandar, and Jaan H. Pu.
2021. "A Comparative Study between Sand- and Gravel-Bed Open Channel Flows in the Wake Region of a Bed-Mounted Horizontal Cylinder" *Fluids* 6, no. 7: 239.
https://doi.org/10.3390/fluids6070239