Analysis of Performance of Cavitation Models with Analytically Calculated Coefficients

Abstract

Cavitation is often simulated using a mixture model, which considers the transport of an active scalar, namely the vapor fraction αv. Source and sink terms of the transport equation of αv, namely vaporization and condensation terms, rule the dynamics of the cavity and are described through different models. These models contain empirical coefficients generally calibrated through optimization processes. The purpose of this paper is to propose an analytical approach for the calculation of the coefficients, based on the time scales of vaporization and condensation processes. Four different models are compared considering as a test-case a two-dimensional flow around a cylinder. Some relevant quantities are analyzed both for standard value of coefficients, as found in the literature, and the coefficients calculated through the analytical approach. The study shows that the analytical computation of the coefficients of the model substantially improve the results, and the models considered give similar results, both in terms of cavitation regime and mean vapor fraction produced.

A Comprehensive Numerical Study of a Wedge-Shaped Textured Convergent Oil Film Gap

“…The boundary condition of zero gradient is applied to all the other surfaces that are not mentioned. Table 2 shows the oil and cavitation parameters used for the simulation model, as presented in [33,34]. The geometry was discretized using second order 3D tetrahedron-shaped elements.…”

Influence of turbulence models in the prediction of cavitation occurrence

“…Over the past years, several approaches were developed to model cavitation phenomena: among the conducted studies, many engineering applications are based on the use of homogeneous mixture models, easy to be employed in large-scale cavitation cases, Ghahramani et al (2021). They are further divided into two groups: barotropic state equation-based models and transport equation models, Savio et al (2021). The former is properly adapted to describe the choke effect on the flow rate but its greater lack is about a proper prediction of cavitation dynamics under turbulent flow conditions, Ducoin et al (2012).…”