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arXiv · 2105.14858

Numerical investigation of three-dimensional partial cavitation in a Venturi geometry

Camille Gouin·Carlos Junqueira-Junior·Eric Goncalves da Silva·Jean-Christophe Robinet
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Abstract

Sheet cavitation appears in many hydraulic applicationss and can lead to technical issues. Some fundamental outcomes such as the complex topology of 3-Dimensional cavitation pockets and their associated dynamics need to be carefully visited.In the present paper, the dynamics of partial cavitation developing in a 3-D Venturi geometry and the interaction with sidewalls are numerically investigated. The simulations are performed usinf a one-fluid compressible Reynolds-Averaged Navier-Stokes (RANS solver associated to a non-linear turbulence model and a void transport-equation model. A detailed analysis of this cavitating flow is carried out using innovative tools such as Spectral Proper Orthogonal Decompositions. Particular attenttion is paid in the study of 3-D effects by comparing numerical results obtained with sidewalls and periodic conditions. A three-dimensional dynamics of the sheet cavitation, unrelated to the presence of sidewalls, is identified and discussed.

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Camille Gouin, Carlos Junqueira-Junior, Eric Goncalves da Silva, Jean-Christophe Robinet. 2021-05-31. Numerical investigation of three-dimensional partial cavitation in a Venturi geometry. https://doi.org/10.1063/5.0052913

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