Formulations and Validations of a High-Precision Volume-of-Fluid Algorithm on Nonorthogonal Meshes for Numerical Simulations of Gas Entrainment Phenomena

Ito, Kei; Kunugi, Tomoaki; Ohshima, Hiroyuki; Kawamura, Takumi

doi:10.1080/18811248.2007.9711542

Cited by 32 publications

(25 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A three-dimensional CFD can consider the non-linearity and locality of the GE phenomena and therefore, the CFD can be a reliable GE evaluation method. In fact, the authors developed a high-precision numerical simulation algorithm for gas-liquid two-phase flows and confirmed that the GE phenomena in a simple experiment can be reproduced by the CFD (2) . However, such a two-phase flow simulation needs very high computational costs and a simpler method is also necessary to evaluate the GE occurrences roughly with lower computational costs.…”

Section: Introductionmentioning

confidence: 89%

Study on Turbulent Modeling in Gas Entrainment Evaluation Method

Ito

Ohshima

Nakamine

et al. 2012

JPES

Self Cite

View full text Add to dashboard Cite

Suppression of gas entrainment (GE) phenomena caused by free surface vortices are very important to establish an economically superior design of the sodium-cooled fast reactor in Japan (JSFR). However, due to the non-linearity and/or locality of the GE phenomena, it is not easy to evaluate the occurrences of the GE phenomena accurately. In other words, the onset condition of the GE phenomena in the JSFR is not predicted easily based on scaled-model and/or partial-model experiments. Therefore, the authors are developing a CFD-based evaluation method in which the non-linearity and locality of the GE phenomena can be considered. In the evaluation method, macroscopic vortex parameters, e.g. circulation, are determined by three-dimensional CFD and then, GE-related parameters, e.g. gas core (GC) length, are calculated by using the Burgers vortex model. This procedure is efficient to evaluate the GE phenomena in the JSFR. However, it is well known that the Burgers vortex model tends to overestimate the GC length due to the lack of considerations on some physical mechanisms. Therefore, in this study, the authors develop a turbulent vortex model to evaluate the GE phenomena more accurately. Then, the improved GE evaluation method with the turbulent viscosity model is validated by analyzing the GC lengths observed in a simple experiment. The evaluation results show that the GC lengths analyzed by the improved method are shorter in comparison to the original method, and give better agreement with the experimental data.

show abstract

Section: Introductionmentioning

confidence: 89%

Study on Turbulent Modeling in Gas Entrainment Evaluation Method

Ito

Ohshima

Nakamine

et al. 2012

JPES

Self Cite

View full text Add to dashboard Cite

show abstract

“…The developed high-precision numerical simulation algorithms are validated by simulating the GE phenomena in a simple experiment (Ito et al 2009). Figure 15 shows the experimental apparatus (Okamoto et al, 2004) In the rectangular channel, uniform inlet flow (0.10 m/s) from the left boundary (in Fig.…”

Section: Numerical Simulation Of Ge Phenomenamentioning

confidence: 99%

“…The other issues is the accurate simulation of interfacial dynamics (interfacial deformation), which is addressed by developing an interface-tracking algorithm based on the high-precision volume-of-fluid algorithm on unstructured meshes (Ito et al, 2007). The physically appropriate formulations of momentum and pressure calculations near a gas-liquid interface are also derived to consider the physical mechanisms correctly in numerical simulations (Ito & Kunugi, 2009). …”

Section: General Description Of High-precision Numerical Simulation Amentioning

confidence: 99%

CFD-based Evaluation of Interfacial Flows

Ito¹,

Ohshima²,

Sakai³

et al. 2010

Computational Fluid Dynamics

Self Cite

View full text Add to dashboard Cite

“…A different approach consists in performing numerical simulations in order to reproduce the formation and evolution of free surface vortices. Several studies (Sakai et al [12], Ito et al [13], Cristofano et al [14]) were performed in the last years, adopting this approach, but the deformation of gas-liquid interface, combined with the swirling motion in the vortex core, makes the numerical simulation of free surface vortex extremely difficult to be performed accurately.…”

Section: Introductionmentioning

confidence: 99%

Experimental Investigation on Free Surface Vortices Driven by Tangential Inlets

Caruso¹,

Cristofano²,

Nobili³

et al. 2016

IJHT

View full text Add to dashboard Cite

Particle Image Velocimetry (PIV) measurements have been carried out in order to analyze the structure of free surface vortices in a promoting geometry with two tangential inlets. Velocity fields associated to the free surface vortex have been obtained at different horizontal planes and Reynolds numbers. Average velocity fields have been calculated and tangential velocity profiles have been compared at different vortex stages and measurement planes. The results show that tangential flow is uniform along the vortex axis and it scales well with the average exit velocity. The tangential velocity profiles, in comparison to the potential behavior, show discrepancies especially at large distances from the vortex axis. Vorticity fields and circulation profiles have been also derived from the measured velocity fields and discussed. The circulation profiles increase along the vortex radius even at large distances from the vortex axis, so that the potential solution is not applicable at all. The comparison of tangential velocity and circulation profiles between promoted and free vortices, the last presented in a previous paper, shows that the tangential motion in a driven vortex is more intense and predominant over the sink effect (radial motion), except very close to the tank bottom, as in a forced configuration (i.e. rotating cylindrical tank).

show abstract

Formulations and Validations of a High-Precision Volume-of-Fluid Algorithm on Nonorthogonal Meshes for Numerical Simulations of Gas Entrainment Phenomena

Cited by 32 publications

References 9 publications

Study on Turbulent Modeling in Gas Entrainment Evaluation Method

Study on Turbulent Modeling in Gas Entrainment Evaluation Method

CFD-based Evaluation of Interfacial Flows

Experimental Investigation on Free Surface Vortices Driven by Tangential Inlets

Contact Info

Product

Resources

About