Investigation of cavitation and vapor shedding mechanisms in a Venturi nozzle

Investigation of cavitation and vapor shedding mechanisms in a Venturi nozzle

Brunhart, Maxwell (Delphi Technologies)
Soteriou, Celia (Delphi Technologies)
Gavaises, Manolis (City University of London)
Karathanassis, Ioannis (City University of London)
Koukouvinis, Phoevos (City University of London)
Jahangir, S. (TU Delft Multi Phase Systems)
Poelma, C. (TU Delft Multi Phase Systems)

2020

Cavitating flow dynamics are investigated in an axisymmetric converging–diverging Venturi nozzle. Computational Fluid Dynamics (CFD) results are compared with those from previous experiments. New analysis performed on the quantitative results from both datasets reveals a coherent trend and shows that the simulations and experiments agree well. The CFD results have confirmed the interpretation of the high-speed images of the Venturi flow, which indicated that there are two vapor shedding mechanisms that exist under different running conditions: re-entrant jet and condensation shock. Moreover, they provide further details of the flow mechanisms that cannot be extracted from the experiments. For the first time with this cavitating Venturi nozzle, the re-entrant jet shedding mechanism is reliably achieved in CFD simulations. The condensation shock shedding mechanism is also confirmed, and details of the process are presented. These CFD results compare well with the experimental shadowgraphs, space–time plots, and time-averaged reconstructed computed tomography slices of vapor fraction.

http://resolver.tudelft.nl/uuid:eca95016-d600-4fd6-aa3f-708e07201ac2

https://doi.org/10.1063/5.0015487

1070-6631

Physics of Fluids, 32 (8)

Institutional Repository

journal article

© 2020 Maxwell Brunhart, Celia Soteriou, Manolis Gavaises, Ioannis Karathanassis, Phoevos Koukouvinis, S. Jahangir, C. Poelma