# Numerical Investigation and Optimization of the Flow Characteristics of Bend Pipe with Different Bending Angles

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Physical and Numerical Methods

#### 2.1. Physical Models

#### 2.2. Numerical Methods

^{−5}.

## 3. Results and Discussion

#### 3.1. Global Flow Analysis

#### 3.2. Wake Development

^{3}), and ${u}_{in}$ is the average inlet velocity (m/s).

#### 3.3. Pressure Loss

## 4. Structure Optimization

#### 4.1. Different Thick-Diameter Ratio

#### 4.2. Different Length-Diameter Ratio

## 5. Conclusions and Prospects

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 3.**Verification of numerical method: (

**a**) flow field distribution; (

**b**) the relative velocity of the horizontal center line.

**Figure 6.**Pressure distribution on the downstream cross−section of the bend pipe with different bending angles.

**Figure 7.**Velocity slices of bend pipe with different bending angles at different downstream distances.

**Figure 9.**Velocity distribution of (

**a**) horizontal and (

**b**) vertical centerline at 0.67D cross−section of downstream bend pipe with different bending angles.

**Figure 13.**Velocity contour and streamline distribution of 0.67D section downstream of 90° bend pipe with different thick-diameter ratio deflectors.

**Figure 15.**Velocity distribution of (

**a**) horizontal and (

**b**) vertical centerline of 0.67D cross−section downstream of 90° bend pipe with different thick−diameter ratio deflectors installed.

**Figure 16.**Velocity distribution of (

**a**) horizontal and (

**b**) vertical center line at 0.67D cross−section downstream of 90° bend pipe with different length−diameter ratio deflectors installed.

No. | Mesh Number (×10^{4}) | Pressure Coefficient | Relative Error (%) |
---|---|---|---|

1 | 45 | 1.3972 | 0.59 |

2 | 90 | 1.4055 | 1.03 |

3 | 140 | 1.4201 | 0.53 |

4 | 170 | 1.4277 | 0.16 |

5 | 200 | 1.4300 | 0.26 |

6 | 260 | 1.4336 | —— |

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**MDPI and ACS Style**

Zhang, J.; Wang, D.; Wang, W.; Zhu, Z.
Numerical Investigation and Optimization of the Flow Characteristics of Bend Pipe with Different Bending Angles. *Processes* **2022**, *10*, 1510.
https://doi.org/10.3390/pr10081510

**AMA Style**

Zhang J, Wang D, Wang W, Zhu Z.
Numerical Investigation and Optimization of the Flow Characteristics of Bend Pipe with Different Bending Angles. *Processes*. 2022; 10(8):1510.
https://doi.org/10.3390/pr10081510

**Chicago/Turabian Style**

Zhang, Jianyi, Dongrui Wang, Weiwei Wang, and Zuchao Zhu.
2022. "Numerical Investigation and Optimization of the Flow Characteristics of Bend Pipe with Different Bending Angles" *Processes* 10, no. 8: 1510.
https://doi.org/10.3390/pr10081510