<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The suction side of a surface piercing hydrofoil, as a section of a Surface Piercing Propeller (SPP), is usually exposed to three phases of flow consisting air, water, and vapour. Hence, ventilation and cavitation pattern of such section during the initial phase of water entry plays an essential role for the propeller’s operational curves. Accordingly, in the current paper a numerical simulation of a simple surface piercing hydrofoil in the form of an oblique wedge is conducted in three-phase environment by using the coupled URANS and VOF equations. The obtained results are validated against water entry experiments and super-cavitation tunnel test data. The resulting pressure curves and free surface profiles of the wedge water entry are presented for different velocity ratios ranging from 0.12 to 0.64. Non-dimensional forces and efficiency relations are defined in order to present the wedge water entry characteristics. Congruent patterns are observed between the performance curves of the propeller and the wedge in different fully ventilated or partially cavitated operation modes. The transition trend from fully ventilated to partially cavitated operation of the surface piercing section of a SPP is studied and analyzed through wedge’s performance during the transitional period.</p></abstract>

The suction side of a surface piercing hydrofoil, as a section of a Surface Piercing Propeller (SPP), is usually exposed to three phases of flow consisting air, water, and vapour. Hence, ventilation and cavitation pattern of such section during the initial phase of water entry plays an essential role for the propeller’s operational curves. Accordingly, in the current paper a numerical simulation of a simple surface piercing hydrofoil in the form of an oblique wedge is conducted in three-phase environment by using the coupled URANS and VOF equations. The obtained results are validated against water entry experiments and super-cavitation tunnel test data. The resulting pressure curves and free surface profiles of the wedge water entry are presented for different velocity ratios ranging from 0.12 to 0.64. Non-dimensional forces and efficiency relations are defined in order to present the wedge water entry characteristics. Congruent patterns are observed between the performance curves of the propeller and the wedge in different fully ventilated or partially cavitated operation modes. The transition trend from fully ventilated to partially cavitated operation of the surface piercing section of a SPP is studied and analyzed through wedge’s performance during the transitional period.

Analysis of Ventilation Regimes of the Oblique Wedge-Shaped Surface Piercing Hydrofoil During Initial Water Entry Process

Polish Maritime Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The suction side of a surface piercing hydrofoil, as a section of a Surface Piercing Propeller (SPP), is usually exposed to three phases of flow consisting...

Analysis of Ventilation Regimes of the Oblique Wedge-Shaped Surface Piercing Hydrofoil During Initial Water Entry Process

Published Online: Apr 11, 2018

Page range: 33 - 43

DOI: https://doi.org/10.2478/pomr-2018-0003

Keywords
emi-submerged propeller, wedge water entry, ventilation pattern, free surface profile

© 2018 Parviz Ghadimi et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Analysis of Ventilation Regimes of the Oblique Wedge-Shaped Surface Piercing Hydrofoil During Initial Water Entry Process

Published Online: Apr 11, 2018

Page range: 33 - 43

DOI: https://doi.org/10.2478/pomr-2018-0003

Keywordsemi-submerged propeller, wedge water entry, ventilation pattern, free surface profile

© 2018 Parviz Ghadimi et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
emi-submerged propeller, wedge water entry, ventilation pattern, free surface profile