# Hydraulic Characteristics of Emerged Rigid and Submerged Flexible Vegetations in the Riparian Zone

^{1}

^{2}

^{3}

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## Abstract

**:**

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Experiment Apparatus

^{3}) is 5 cm from the sensing elements, and it can measure mean velocity and velocity fluctuation. Via a processing card, the probe was connected to the computer [11]. Real-time data could be recorded using a data acquisition program installed in the sampling computer.

#### 2.2. Vegetation Material

^{2}and the top view of the vegetation can be seen in Figure 3.

#### 2.3. Experiment Method

#### 2.4. Experimental Conditions

#### 2.5. Locations of Flow Measurement

## 3. Analytical Method

#### 3.1. Mean Velocity

#### 3.2. Turbulence Intensity

#### 3.3. Flow Resistance Coefficient

## 4. Results and Discussions

#### 4.1. Mean Velocity Profiles

#### 4.2. Turbulence Intensities

#### 4.3. Reynold Stress

#### 4.4. Manning Coefficient $n$

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 4.**Test run S9 with grasses. (

**a**) The average flow velocity is 0. (

**b**) The average flow velocity is 0.23 m/s.

**Figure 5.**Vertical distributions of point velocity at vertical 4 with Q = 20 L/s for different vegetations: reed and stick at the length of 30 cm, grass at the length of 10 cm, and the chlorella at the length of 5–6 cm.

**Figure 6.**Vertical distributions of $RM{S}_{u}$, $RM{S}_{v}$ and $RM{S}_{w}$ at the vertical 5 with Q = 30 L/s for different vegetations: reed and stick at the length of 30 cm, grass at the length of 10 cm, and the chlorella at the length of 5–6 cm. (

**a**) Vertical distributions of $RM{S}_{u}$; (

**b**) Vertical distributions of $RM{S}_{v}$; (

**c**) Vertical distributions of $RM{S}_{w}$.

**Figure 7.**Vertical distributions of $-\overline{{u}^{\prime}{v}^{\prime}}$, $-\overline{{u}^{\prime}{w}^{\prime}}$ and $-\overline{{v}^{\prime}{w}^{\prime}}$ at verticals 3 and 5, respectively, with Q = 20 L/s for four different vegetations: reed and stick at the length of 30 cm, grass at the length of 10 cm, and the chlorella at the length of 5–6 cm: (

**a**) Vertical distributions of $-\overline{{u}^{\prime}{v}^{\prime}}$ at verticals 3 with Q = 20 L/s; (

**b**) Vertical distributions of $-\overline{{u}^{\prime}{w}^{\prime}}$ at verticals 3 with Q = 20 L/s; (

**c**) Vertical distributions of $-\overline{{v}^{\prime}{w}^{\prime}}$ at verticals 3 with Q = 20 L/s; (

**d**) Vertical distributions of $-\overline{{u}^{\prime}{v}^{\prime}}$ at verticals 5 with Q = 20 L/s; (

**e**) Vertical distributions of $-\overline{{u}^{\prime}{w}^{\prime}}$ at verticals 5 with Q = 20 L/s; (

**f**) Vertical distributions of $-\overline{{v}^{\prime}{w}^{\prime}}$ at verticals 5 with Q = 20 L/s.

**Figure 8.**Manning coefficient n for various vegetations: (

**a**,

**b**): n against relative depth, z/h, where z is the height if measurement location, h is the water depth; (

**c**) n against the Froude number, Fr.

Scheme | Data Number | H (cm) | Discharge (L/s) | Vegetation | Re | Fr | |
---|---|---|---|---|---|---|---|

S1 | Run01 | 15 | 10.00 | reed | stick | 10,967 | 0.0082 |

S2 | Run02 | 15 | 10.00 | grass | chlorella | 10,967 | 0.0082 |

S3 | Run03 | 15 | 15.00 | reed | stick | 16,620 | 0.0189 |

S4 | Run04 | 15 | 15.00 | grass | chlorella | 16,620 | 0.0189 |

S5 | Run05 | 15 | 20.00 | reed | stick | 22,134 | 0.0335 |

S6 | Run06 | 15 | 20.00 | grass | chlorella | 22,134 | 0.0335 |

S7 | Run07 | 15 | 25.00 | reed | stick | 27,697 | 0.0525 |

S8 | Run08 | 15 | 25.00 | grass | chlorella | 27,697 | 0.0525 |

S9 | Run09 | 15 | 30.00 | reed | stick | 33,200 | 0.0754 |

S10 | Run10 | 15 | 30.00 | grass | chlorella | 33,200 | 0.0754 |

S11 | Run11 | 20 | 10.00 | reed | stick | 9930 | 0.0035 |

S12 | Run12 | 20 | 10.00 | grass | chlorella | 9930 | 0.0035 |

S13 | Run13 | 20 | 15.00 | reed | stick | 14,955 | 0.0080 |

S14 | Run14 | 20 | 15.00 | grass | chlorella | 14,955 | 0.0080 |

S15 | Run15 | 20 | 20.00 | reed | stick | 19,944 | 0.0142 |

S16 | Run16 | 20 | 20.00 | grass | chlorella | 19,944 | 0.0142 |

S17 | Run17 | 20 | 25.00 | reed | stick | 24,885 | 0.0221 |

S18 | Run18 | 20 | 25.00 | grass | chlorella | 24,885 | 0.0221 |

S19 | Run19 | 20 | 30.00 | reed | stick | 29,910 | 0.0319 |

S20 | Run20 | 20 | 30.00 | grass | chlorella | 29,910 | 0.0319 |

S21 | Run21 | 25 | 10.00 | reed | stick | 9068 | 0.0018 |

S22 | Run22 | 25 | 10.00 | grass | chlorella | 9068 | 0.0018 |

S23 | Run23 | 25 | 15.00 | reed | stick | 13,596 | 0.0041 |

S24 | Run24 | 25 | 15.00 | grass | chlorella | 13,596 | 0.0041 |

S25 | Run25 | 25 | 20.00 | reed | stick | 18,082 | 0.0072 |

S26 | Run26 | 25 | 20.00 | grass | chlorella | 18,082 | 0.0072 |

S27 | Run27 | 25 | 25.00 | reed | stick | 22,664 | 0.0113 |

S28 | Run28 | 25 | 25.00 | grass | chlorella | 22,664 | 0.0113 |

S29 | Run29 | 25 | 30.00 | reed | stick | 27,191 | 0.0163 |

S30 | Run30 | 25 | 30.00 | grass | chlorella | 27,191 | 0.0163 |

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**MDPI and ACS Style**

Meng, X.; Zhou, Y.; Sun, Z.; Ding, K.; Chong, L. Hydraulic Characteristics of Emerged Rigid and Submerged Flexible Vegetations in the Riparian Zone. *Water* **2021**, *13*, 1057.
https://doi.org/10.3390/w13081057

**AMA Style**

Meng X, Zhou Y, Sun Z, Ding K, Chong L. Hydraulic Characteristics of Emerged Rigid and Submerged Flexible Vegetations in the Riparian Zone. *Water*. 2021; 13(8):1057.
https://doi.org/10.3390/w13081057

**Chicago/Turabian Style**

Meng, Xin, Yubao Zhou, Zhilin Sun, Kaixuan Ding, and Lin Chong. 2021. "Hydraulic Characteristics of Emerged Rigid and Submerged Flexible Vegetations in the Riparian Zone" *Water* 13, no. 8: 1057.
https://doi.org/10.3390/w13081057