# Experimental Study of Supercavitation Bubble Development over Bodies in a Duct Flow

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## Abstract

**:**

## 1. Introduction

## 2. Problem Description

## 3. The Experimental System and Flow Conditions

## 4. Results

#### 4.1. Stages of Bubble Development

#### 4.2. The Pressure Field

#### 4.3. Comparison of Results with Theoretical Analysis

#### 4.4. The Bubble Dimensions

## 5. “Hysteresis”

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 7.**The wall pressure in P5 vs. the velocity in this section for the three cavitators 1.

**Figure 8.**Control volume for theoretical analyses. (

**a**) the cavitation does not reach the cross-section (

**b**) the cavitation reaches the cross-section.

**Figure 9.**Comparison between the theoretical and experimental values of $\Delta P={P}_{5}-{P}_{t}$ vs. the velocity at the nozzle throat for the different cavitators.

**Figure 10.**Comparison between the theoretical prediction and experimental results of the bubble geometry for the three cavitators.

**Figure 11.**The measured supercavitation bubble dimension ratio vs. the cavitation number for the three cavitators.

**Figure 12.**Wall pressure at the diverging part of the nozzle vs. the velocity for the spherical cavitator during a cycle including an increase followed a decrease of the flow velocity.

**Table 1.**Flow velocity at the front edge of the cavitator in Stages 1–6 of the bubble development for the three cavitators.

Stage of Development | Conical Cavitator | Spherical Cavitator | Flat Cavitator |
---|---|---|---|

Stage 1 | 14.8 m/s | 13.5 m/s | 9.9 m/s |

Stage 2 | 16.4 m/s | 15.8 m/s | 11.7 m/s |

Stage 3 | 17.2 m/s | 16.8 m/s | 13.8 m/s |

Stage 4 | 17.8 m/s | 17.3 m/s | 15.5 m/s |

Stage 5 | 19.7 m/s | 18.3 m/s | 17.7 m/s |

Stage 6 | 20.7 m/s | 19.8 m/s | 18.8 m/s |

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**MDPI and ACS Style**

Arad Ludar, L.; Gany, A. Experimental Study of Supercavitation Bubble Development over Bodies in a Duct Flow. *J. Mar. Sci. Eng.* **2020**, *8*, 28.
https://doi.org/10.3390/jmse8010028

**AMA Style**

Arad Ludar L, Gany A. Experimental Study of Supercavitation Bubble Development over Bodies in a Duct Flow. *Journal of Marine Science and Engineering*. 2020; 8(1):28.
https://doi.org/10.3390/jmse8010028

**Chicago/Turabian Style**

Arad Ludar, Lotan, and Alon Gany. 2020. "Experimental Study of Supercavitation Bubble Development over Bodies in a Duct Flow" *Journal of Marine Science and Engineering* 8, no. 1: 28.
https://doi.org/10.3390/jmse8010028