Abstract
The present paper focuses on the numerical simulation of unsteady cavitation around a NACA66 hydrofoil to improve the understanding of the cavitation effects on hydraulic machinery. For this aim, the Zwart–Gerber–Belamri cavitation model was updated and uploaded as a library file for OpenFOAM’s solvers using C++ language. Furthermore, the hybrid Reynold average Navier–Stokes (RANS)–large eddy simulation (LES) model k - ω SST scale adaptive simulation (SAS) was implemented as a turbulence model for the present study of scale adaptive simulation. For validation, numerical results were compared with experimental results obtained by Leroux at the Naval Academy Research Institute in France. In order to highlight the benefits in terms of computational consumption and reproduction of the phenomenon the k - ω SST SAS model was compared against implicit large eddy simulation (ILES). Results show that the cavitation evolution including the maximum vapor length, the detachment and the oscillation frequency were reproduced satisfactorily using k - ω SST SAS. Moreover, k - ω SST SAS results predicted a lower total vapor volume on time than ILES, which is related to observed pulses of pressure coefficient, C p , and those match fairly well with the experimental results. To summarize, the k - ω SST SAS model predicts with good accuracy unsteady cavitation behavior around hydrofoils and shows improved versatility over the ILES approach.
Highlights
Studies of unsteady cavitating flow around hydrofoils are important to understand the cavitation dynamic behavior and its impact in hydraulic machinery [1,2]
The highest pulse is observed at 4.01 Hz in both cases, and it matches the frequency of the experimental result obtained by Leroux [22]
implicit large eddy simulation (ILES) presented additional pulses related to subgrid scale (SGS), which may contribute to the large computational resources demanded by ILES
Summary
Studies of unsteady cavitating flow around hydrofoils are important to understand the cavitation dynamic behavior and its impact in hydraulic machinery [1,2]. Based on previous studies of Lu et al [10], Hidalgo et al [4] applied implicit large eddy simulation (ILES) for the numerical simulation of unsteady cavitating flows around a plane–convex hydrofoil. [17] proposed a RANS–LES turbulence model called scale adaptive simulation (SAS) which is based on previous studies carried out by Menter [20,21]. The use of SAS for numerical simulations of unsteady cavitating flows around hydrofoils has not been widely explored yet, and the model mechanics of the scale–adaptive characteristics in regions as the detached process of cavities is not fully understood [19]. For a better understanding of the SAS model and to capture major trends, ILES has been carried out for the numerical simulation of unsteady cloud cavitation flows around a NACA66 hydrofoil. The comparison is based on the methodology proposed by Edgar et al [23]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
