Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator
In this paper, the ITTC Standard Cavitator is numerically investigated in a cavitation tunnel. Simulations at different cavitation numbers are compared against experiments conducted in the cavitation tunnel of SVA Potsdam. The focus is placed on the numerical prediction of sheet-cavitation dynamics...
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doaj-86b0bf19d9ad4e7ab1beacd2231517a12020-11-25T02:46:40ZengMDPI AGApplied Sciences2076-34172020-10-01106985698510.3390/app10196985Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard CavitatorVille M. Viitanen0Tuomas Sipilä1Antonio Sánchez-Caja2Timo Siikonen3VTT Technical Research Centre of Finland Ltd., 02150 Espoo, FinlandABB Marine and Ports, 00980 Helsinki, FinlandVTT Technical Research Centre of Finland Ltd., 02150 Espoo, FinlandDepartment of Mechanical Engineering, Aalto University, 02150 Espoo, FinlandIn this paper, the ITTC Standard Cavitator is numerically investigated in a cavitation tunnel. Simulations at different cavitation numbers are compared against experiments conducted in the cavitation tunnel of SVA Potsdam. The focus is placed on the numerical prediction of sheet-cavitation dynamics and the analysis of transient phenomena. A compressible two-phase flow model is used for the flow solution, and two turbulence closures are employed: a two-equation unsteady RANS model, and a hybrid RANS/LES model. A homogeneous mixture model is used for the two phases. Detailed analysis of the cavitation shedding mechanism confirms that the dynamics of the sheet cavitation are dictated by the re-entrant jet. The break-off cycle is relatively periodic in both investigated cases with approximately constant shedding frequency. The CFD predicted sheet-cavitation shedding frequencies can be observed also in the acoustic measurements. The Strouhal numbers lie within the usual ranges reported in the literature for sheet-cavitation shedding. We furthermore demonstrate that the vortical flow structures can in certain cases develop striking cavitating toroidal vortices, as well as pressure wave fronts associated with a cavity cloud collapse event. To our knowledge, our numerical analyses are the first reported for the ITTC standard cavitator.https://www.mdpi.com/2076-3417/10/19/6985hydrodynamic cavitationcompressible two-phase flowturbulence modellingsystem instabilities |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Ville M. Viitanen Tuomas Sipilä Antonio Sánchez-Caja Timo Siikonen |
spellingShingle |
Ville M. Viitanen Tuomas Sipilä Antonio Sánchez-Caja Timo Siikonen Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator Applied Sciences hydrodynamic cavitation compressible two-phase flow turbulence modelling system instabilities |
author_facet |
Ville M. Viitanen Tuomas Sipilä Antonio Sánchez-Caja Timo Siikonen |
author_sort |
Ville M. Viitanen |
title |
Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator |
title_short |
Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator |
title_full |
Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator |
title_fullStr |
Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator |
title_full_unstemmed |
Compressible Two-Phase Viscous Flow Investigations of Cavitation Dynamics for the ITTC Standard Cavitator |
title_sort |
compressible two-phase viscous flow investigations of cavitation dynamics for the ittc standard cavitator |
publisher |
MDPI AG |
series |
Applied Sciences |
issn |
2076-3417 |
publishDate |
2020-10-01 |
description |
In this paper, the ITTC Standard Cavitator is numerically investigated in a cavitation tunnel. Simulations at different cavitation numbers are compared against experiments conducted in the cavitation tunnel of SVA Potsdam. The focus is placed on the numerical prediction of sheet-cavitation dynamics and the analysis of transient phenomena. A compressible two-phase flow model is used for the flow solution, and two turbulence closures are employed: a two-equation unsteady RANS model, and a hybrid RANS/LES model. A homogeneous mixture model is used for the two phases. Detailed analysis of the cavitation shedding mechanism confirms that the dynamics of the sheet cavitation are dictated by the re-entrant jet. The break-off cycle is relatively periodic in both investigated cases with approximately constant shedding frequency. The CFD predicted sheet-cavitation shedding frequencies can be observed also in the acoustic measurements. The Strouhal numbers lie within the usual ranges reported in the literature for sheet-cavitation shedding. We furthermore demonstrate that the vortical flow structures can in certain cases develop striking cavitating toroidal vortices, as well as pressure wave fronts associated with a cavity cloud collapse event. To our knowledge, our numerical analyses are the first reported for the ITTC standard cavitator. |
topic |
hydrodynamic cavitation compressible two-phase flow turbulence modelling system instabilities |
url |
https://www.mdpi.com/2076-3417/10/19/6985 |
work_keys_str_mv |
AT villemviitanen compressibletwophaseviscousflowinvestigationsofcavitationdynamicsfortheittcstandardcavitator AT tuomassipila compressibletwophaseviscousflowinvestigationsofcavitationdynamicsfortheittcstandardcavitator AT antoniosanchezcaja compressibletwophaseviscousflowinvestigationsofcavitationdynamicsfortheittcstandardcavitator AT timosiikonen compressibletwophaseviscousflowinvestigationsofcavitationdynamicsfortheittcstandardcavitator |
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