Capturing the Pinch-Off of Liquid Jets by the Level Set Method

2003 ◽  
Vol 125 (5) ◽  
pp. 922-927 ◽  
Author(s):  
Y. Pan ◽  
K. Suga
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Density Ratio ◽  
Three Dimensional ◽  
Liquid Jets ◽  
Surface Phenomena ◽  
Two Phase ◽  
Dynamic Simulations ◽  
Fine Grid ◽  
Radial Profiles

Full three-dimensional dynamic simulations of forced liquid jets flowing into and pinching off in ambient of another liquid were performed by using the level set method for tracking the interface between the immiscible materials. The simulations were performed for jets with viscosity ratios between the inner and outer fluids of 0.17 and 1.7. The jets were forced at Strouhal number of 4.0. The Reynolds, Froud, and Bond numbers based on the conditions at the nozzle exit were 34–35, 0.2, and 6.1, for both cases. The numerical results are compared with the data from the experiment made by Longmire et al. (2001). The comparisons were made for (1) flow images of one complete pinch-off cycle and (2) the axial and radial profiles of the instantaneous velocities around the region of jet disintegration. The feasibility and accuracy of using the level set method in multiphase problems involving interface breakup/coalescence is explored and accessed by simulating such relatively low speed, low density-ratio two-phase flows. Although the level set method is quite promising, due to the surface tension model, it requires very fine grid resolution (the Weber number based on the grid spacing is smaller than 10−2) even for capturing the laminar surface phenomena.

An Improved Three-Dimensional Level Set Method for Gas-Liquid Two-Phase Flows

2004 ◽  
Vol 126 (4) ◽  
pp. 578-585 ◽  
Author(s):  
Hiroyuki Takahira ◽  
Tomonori Horiuchi ◽  
Sanjoy Banerjee
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Stokes Equations ◽  
Interpolation Method ◽  
Density Ratio ◽  
Three Dimensional ◽  
Mass Conservation ◽  
Staggered Grid ◽  
Two Phase ◽  
Level Set Function

For the present study, we developed a three-dimensional numerical method based on the level set method that is applicable to two-phase systems with high-density ratio. The present solver for the Navier-Stokes equations was based on the projection method with a non-staggered grid. We improved the treatment of the convection terms and the interpolation method that was used to obtain the intermediate volume flux defined on the cell faces. We also improved the solver for the pressure Poisson equations and the reinitialization procedure of the level set function. It was shown that the present solver worked very well even for a density ratio of the two fluids of 1:1000. We simulated the coalescence of two rising bubbles under gravity, and a gas bubble bursting at a free surface to evaluate mass conservation for the present method. It was also shown that the volume conservation (i.e., mass conservation) of bubbles was very good even after bubble coalescence.

An Improved Three-Dimensional Level Set Method for Gas-Liquid Two-Phase Flows (Keynote)

2003 ◽  
Author(s):  
Hiroyuki Takahira ◽  
Tomonori Horiuchi ◽  
Sanjoy Banerjee
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Stokes Equations ◽  
Interpolation Method ◽  
Density Ratio ◽  
Three Dimensional ◽  
Mass Conservation ◽  
Staggered Grid ◽  
Two Phase ◽  
Level Set Function

For the present study, we developed a three-dimensional numerical method based on the level set method that is applicable to two-phase systems with high-density ratio. The present solver for the Navier-Stokes equations was based on the projection method with a non-staggered grid. We improved the treatment of the convection terms and the interpolation method that was used to obtain the intermediate volume flux defined on the cell faces. We also improved the solver for the pressure Poisson equations and the reinitialization procedure of the level set function. It was shown that the present solver worked very well even for a density ratio of the two fluids of 1:1000. We simulated the coalescence of two rising bubbles under gravity, and a gas bubble bursting at a free surface to evaluate mass conservation for the present method. It was also shown that the volume conservation (i.e., mass conservation) of bubbles was very good even after bubble coalescence.

scholarly journals Computing three-dimensional two-phase flows with a mass-conserving level set method

2008 ◽  
Vol 11 (4-6) ◽  
pp. 221-235 ◽  
Author(s):  
S. P. van der Pijl ◽  
A. Segal ◽  
C. Vuik ◽  
P. Wesseling
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Three Dimensional ◽  
Two Phase Flows ◽  
Two Phase

Numerical Simulation of Filling Process in Vertical Centrifugal Casting Based on Projection-Level Set Method

2011 ◽  
Vol 314-316 ◽  
pp. 364-368 ◽  
Author(s):  
Jun Zhang ◽  
Jian Xin Zhou ◽  
Ming Yuan Zhang ◽  
Sheng Yong Pang ◽  
Dun Ming Liao ◽  
...  
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Centrifugal Casting ◽  
Three Dimensional ◽  
Thin Wall ◽  
Filling Process ◽  
Two Phase ◽  
Numerical Result ◽  
Complex Part ◽  
Mould Filling

A three-dimensional incompressible two phase flow model of vertical centrifugal casting is proposed to simulate the fluid flow of mould filling process accurately and effectively. The Projection method is adopted to solve the govern equation of the flow field, and the Level Set method is used to capture the free surface. The mold filling of a complex part with thin-wall is simulated. The numerical result shows that the Projection-Level Set method could simulate centrifugal casting effectively. The present study has a guiding significance to the production of vertical centrifugal casting.

Application of Level Set Method to the Simulation of Liquid-Gas Two-Phase Flow during Mold Filling

2008 ◽  
Vol 575-578 ◽  
pp. 43-48 ◽  
Author(s):  
Jing Hao ◽  
Li Liang Chen ◽  
Jian Xin Zhou
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Two Phase Flow ◽  
Density Ratio ◽  
Mold Filling ◽  
Physical Parameters ◽  
Phase Flow ◽  
Mathematical Tool ◽  
Two Phase ◽  
Navier Stokes Equation

Level Set Method is an appropriate mathematical tool for solving two-phase flow problems. The main advantage of Level Set Method is its efficiency to deal with complex interfaces, even if topology changes. In this paper, the liquid-gas two-phase flow is simulated using a combination of Level Set Method and SOLA method. SOLA is used to compute the Navier-Stokes equation, and Level Set Method is used to track the interfaces between the liquid and the gas during mold filling process. The difficulty in the simulation of two-phase flow comes from great change of physical parameters (e.g., density and viscosity) across the interfaces. Level Set Method allows for large density ratio and jump in viscosity without reconstructing the numerical grid. In this work, the forming and moving of the gas bubbles in liquid were numerically simulated by Level Set approach. The numerical simulation results and experiments suggest that Level Set Method is quite reliable and effective for the simulation of liquid-gas two-phase flow during mold filling.

Efficient two-phase mass-conserving level set method for simulation of incompressible turbulent free surface flows with large density ratio

2016 ◽  
Vol 136 ◽  
pp. 212-227 ◽  
Author(s):  
J.M. Cubos-Ramírez ◽  
J. Ramírez-Cruz ◽  
M. Salinas-Vázquez ◽  
W. Vicente-Rodríguez ◽  
E. Martinez-Espinosa ◽  
...  
Keyword(s):  
Free Surface ◽  
Level Set Method ◽  
Level Set ◽  
Density Ratio ◽  
Free Surface Flows ◽  
Two Phase ◽  
Surface Flows ◽  
Large Density ◽  
Large Density Ratio

Implementation of a Level Set Interface Tracking Method in the FIDAP and CFX-4 Codes

2004 ◽  
Author(s):  
Sergey V. Shepel ◽  
Brian L. Smith ◽  
Samuel Paolucci
Keyword(s):  
Level Set ◽  
Gaseous Phase ◽  
Viscosity Ratio ◽  
Density Ratio ◽  
Three Dimensional ◽  
Interface Tracking ◽  
Two Phase ◽  
Computational Fluid Dynamics Cfd ◽  
Liquid Flows ◽  
Level Set Formulation

A Streamline-Upwind/Petrov-Galerkin (SUPG) Finite Element (FE) Level Set method is presented, which may be used for solving problems involving incompressible two-phase flow with moving inter-phase boundaries. The method is three-dimensional, and can be used on both structured and unstructured grids. Two formulations are given. The first considers the coupled motion of both phases, and is implemented in the framework of the commercial Computational Fluid Dynamics (CFD) code CFX-4. The second can be applied for gas-liquid flows when effects of the gaseous phase on the motion of the liquid phase are negligible; consequently, the gaseous phase is removed from consideration. This Level Set formulation is implemented in the commercial CFD code FIDAP. The resulting Level Set formulations are tested on sample problems involving two-phase flows with density ratio of the order of 103 and viscosity ratio as high as 105. The numerical results are compared against experimental data.

Element-local level set method for three-dimensional dynamic crack growth

2009 ◽  
Vol 80 (12) ◽  
pp. 1520-1543 ◽  
Author(s):  
Qinglin Duan ◽  
Jeong-Hoon Song ◽  
Thomas Menouillard ◽  
Ted Belytschko
Keyword(s):  
Crack Growth ◽  
Level Set Method ◽  
Level Set ◽  
Local Level ◽  
Three Dimensional ◽  
Dynamic Crack ◽  
Dynamic Crack Growth ◽  
Local Level Set

Parallelized numerical modeling of the interaction of a solid object with immiscible incompressible two-phase fluid flow

2017 ◽  
Vol 34 (3) ◽  
pp. 709-724 ◽  
Author(s):  
Amirmahdi Ghasemi ◽  
R. Nikbakhti ◽  
Amirreza Ghasemi ◽  
Faraz Hedayati ◽  
Amir Malvandi
Keyword(s):  
Level Set ◽  
Stokes Equations ◽  
Density Ratio ◽  
High Density ◽  
Immersed Boundary ◽  
Immersed Boundary Methods ◽  
Solid Object ◽  
Computational Tool ◽  
Two Phase ◽  
Content Type

Purpose A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of accurate modeling of wave energy converters in which the immense energy of the ocean can be extracted at low cost. Design/methodology/approach The full two-dimensional Navier–Stokes equations are discretized on a regular structured grid, and the two-step projection method along with multi-processing (OpenMP) is used to efficiently solve the flow equations. The level set and the immersed boundary methods are used to capture the free surface of a fluid and a solid object, respectively. The full two-dimensional Navier–Stokes equations are solved on a regular structured grid to resolve the flow field. Level set and immersed boundary methods are used to capture the free surface of liquid and solid object, respectively. A proper contact angle between the solid object and the fluid is used to enhance the accuracy of the advection of the mass and momentum of the fluids in three-phase cells. Findings The computational tool is verified based on numerical and experimental data with two scenarios: a cylinder falling into a rectangular domain due to gravity and a dam breaking in the presence of a fixed obstacle. In the former validation simulation, the accuracy of the immersed boundary method is verified. However, the accuracy of the level set method while the computational tool can model the high-density ratio is confirmed in the dam-breaking simulation. The results obtained from the current method are in good agreement with experimental data and other numerical studies. Practical/implications The computational tool is capable of being parallelized to reduce the computational cost; therefore, an OpenMP is used to solve the flow equations. Its application is seen in the following: wind energy conversion, interaction of solid object such as wind turbine with water waves, etc. Originality/value A high efficient CFD approach method is introduced to capture the interaction of solid object with a two-phase flow where they have high-density ratio. The current method has the ability to efficiently be parallelized.

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