Naslov
A study of cavitation models in computational fluid dynamics

Autori
Niko Primer

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, diplomski rad, diplomski

Fakultet
Fakultet strojarstva i brodogradnje

Mjesto
Zagreb

Datum
10.04

Godina
2020

Stranica
126

Mentor
Jasak, Hrvoje

Ključne riječi
CFD ; cavitation ; Rayleigh-Plesset equation ; Schnerr-Sauer model ; NACA009 Truncated Hydrofoil ; Delft Twist 11 Hydrofoil ; foam-extend ; Open-Foam-7

Sažetak
Cavitation is a natural occurrence of vapor in a flow of liquid, caused by a local drop in pressure. It is a harmful occurrence that disrupts the flow, causes noise and vibrations, and can even inflict structural damage to machine elements. For these reasons, the study of cavitation inception is of particular interest, as is the ability to anticipate cavitation and facilitate the design of engineering devices to avoid the harmful side effects. Thanks to the modern advancements in technology, today, Computational Fluid Dynamics (CFD), is being applied in cavitation research. This thesis explains the current understanding of cavitation inception and presents the mathematical models that describe the behavior of the vapor and liquid phase in cavitating flows. In addition it shows the methods and simplifications, with which those models are used in CFD. In the scope of this thesis, simulations were performed using foam-extend and OpenFOAM software packages, with the purpose of validating the cavitation models. The goal of the thesis was to compare the OpenFOAM implementation of the Schnerr-Sauer cavitation model with experimental results. With that in mind, 2 reference geometries were selected. The first is a 2D mesh in which the NACA009 Truncated Hydrofoil is situated, and it was used for the 2D flow simulations. The second is a 3D geometry in which the Delft Twist 11 Hydrofoil is situated, and it was used for 3D flow simulations. In this study, a total of 12 simulations was performed. Out of those, 8 were on the 2D mesh, and 4 on the 3D mesh. For each inlet velocity, 4 simulations were performed. Both cavitating and non-cavitating flow was simulated, and for each experimental setup, one simulation with turbulence modeling and one without. The results were compared to experimental research results. At the end of the thesis, a brief review of the results and the current state of CFD cavitation research was given.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

POVEZANOST RADA