Numerical simulation of molecular conformation evolution during mold filling process in a complex cavity

It has been proved that the mold filling under low pressure casting can be described by the second order nonlinear differential equations characterized by damping oscillations. To obtain higher accuracy of the velocity field, the mold filling process with damping oscillations should be considered. A computational model taking the liquid level droping in the crucible into account based on two phase flow for filling process of damping oscillations is presented in this paper. Hydraulic simulation with the particle image velocimetry was adopted to verify the numerical simulation result. It is proved that the nemuerical simulation results used the presented model perfecly match with the particle image velocimetry results. Liquid level droping in crucible is the main reason for damping oscillations in mold filling. Velocity oscilations can be eliminated when the melt flow across a sudden expansion section. The detailed flow field based on the presented model can provide guidance to optimize the process parameters.

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Parallel partitioning algorithm for numerical simulation of gas-liquid two-phase flow during the mold filling process

Procedia Manufacturing ◽

10.1016/j.promfg.2019.12.082 ◽

2019 ◽

Vol 37 ◽

pp. 513-519

Author(s):

Yongjia Zhang ◽

Xiang Gao ◽

Xu Shen ◽

Zhiwei Huang ◽

Yajun Yin ◽

...

Keyword(s):

Numerical Simulation ◽

Two Phase Flow ◽

Mold Filling ◽

Phase Flow ◽

Filling Process ◽

Two Phase ◽

Partitioning Algorithm

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Numerical Study on Mold Filling Process of Casting

Materials Science Forum ◽

10.4028/www.scientific.net/msf.575-578.87 ◽

2008 ◽

Vol 575-578 ◽

pp. 87-92

Author(s):

Xiao Qiang Pan ◽

Hong Zhu Sun ◽

Jun Da Chen ◽

Yu Ling Zhu

Keyword(s):

Numerical Simulation ◽

Initial Conditions ◽

Numerical Study ◽

Solidification Process ◽

Mold Filling ◽

General Purpose ◽

Filling Process ◽

Numerical Heat Transfer ◽

Multiphase Fluid Flow ◽

Multiphase Fluid

Techniques of numerical simulation on mold filling process of casting are investigated in this paper. The mathematical model is formed on the ground of some selected theories in computational fluid dynamics (CFD), Numerical Heat Transfer (NHT) and computational methods to interfacial tracking. The discrete solution to the governing equations appeals to Finite Volume Method (FVM) on structured mesh. As for viscous turbulence flow and multiphase fluid flow in mold filling, engineering turbulence model and Volume of Fluid (VOF) method are adopted in the algorithms, respectively. As a debut, the general-purpose CFD software is used to establish the practicable mechanical model for the simulation. By means of numerical simulation, variation and distribution of velocity, temperature, stress and configuration of casting, etc. with respect to time and space in the filling process can be quantitatively analysed in detail, which is helpful for engineers to optimize their design of technics with less time and less cost and is meaningful to provide the subsequent simulation, solidification process of casting, with initial conditions.

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STUDY ON EFFICIENT NUMERICAL SIMULATION TECHNOLOGY OF MOLD FILLING PROCESS OF CASTING

International Journal of Modern Physics B ◽

10.1142/s0217979209061330 ◽

2009 ◽

Vol 23 (06n07) ◽

pp. 1603-1608

Author(s):

LIUSHUAN YANG ◽

XIAO WANG ◽

JINLIANG HUANG ◽

SHAOLI ZHANG

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Simulation Experiment ◽

Mold Filling ◽

Simulation Technology ◽

Filling Process ◽

Calculating Method

The paper based on the SOLA-VOF, depended on the meaning of the equation result in the algebra and geometry, brings forward a new idea and the rapid iterative arithmetic. According to the rapid iterative arithmetic, a program of the rapid calculating method of flow field and the numerical simulation experiment using the standard casting have been made by the author. The result showed that the calculating efficiency has increased by 3~4 times than before, the accuracy equals to the SOLA-VOF, which can meet the requirements of the application.

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Dynamic simulation of fiber orientation in mold filling process in a complex cavity

Acta Physica Sinica ◽

10.7498/aps.61.044701 ◽

2012 ◽

Vol 61 (4) ◽

pp. 044701

Author(s):

Yang Bin-Xin ◽

Ouyang Jie ◽

Li Xue-Juan

Keyword(s):

Dynamic Simulation ◽

Fiber Orientation ◽

Mold Filling ◽

Filling Process ◽

Complex Cavity

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Research of the Interpolation Method Applied to the Numerical Simulation of the Casting Filling Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1037.369 ◽

2014 ◽

Vol 1037 ◽

pp. 369-372

Author(s):

Xiao Chong Lv ◽

Ya Jun Yin ◽

Jian Xin Zhou

Keyword(s):

Numerical Simulation ◽

Temperature Field ◽

Interpolation Method ◽

Interpolation Formula ◽

Mold Filling ◽

Casting Simulation ◽

Filling Process ◽

Process Comparison ◽

Temperature Filed ◽

Last Stage

With the development of computer technology, casting simulation plays an increasingly important role in foundry production. VOF (Volume of Fluid) method which tracks free surfaces is widely used in casting simulation because it is simple to solve and easy to achieve. However, in the last stage of mold filling process, the solution speed of VOF method is very slow because the space to fill becomes smaller. To solve this problem, interpolation formula is applied to the calculation of temperature field and an interpolation method to calculate the last part of temperature field in mold filling process is presented in this paper. The solution is to calculate temperature field of unfilled grids based on the temperature filed of filled grids at the last stage of filling process. Comparison between the results of interpolation method and theoretical calculation illustrates the rationality of the interpolation temperature field in this paper. Numerical simulations of actual castings indicate that the interpolation method can greatly improve the speed of getting temperature field under a certain accuracy. This paper has important implications to the calculation of numerical simulation in mold filling process.

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Numerical Simulation of Die-Casting Mold Filling Process by Using Fractional Step Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.575-578.104 ◽

2008 ◽

Vol 575-578 ◽

pp. 104-108

Author(s):

Jie Yang ◽

Yu Xin Ren ◽

Shou Mei Xiong

Keyword(s):

Numerical Simulation ◽

Die Casting ◽

Mold Filling ◽

Flow Patterns ◽

Fractional Step ◽

Filling Process ◽

Step Method ◽

Fractional Step Method ◽

Time Step ◽

Simulation Results

In the numerical simulation of mold filling process, the calculation efficiency has been a key point for practical applications due to the complexity and thin-section of die castings. In current research work, a fractional step method was applied in the solution of the unsteady Navier-Stokes equations, which can be implemented with a single solution to the momentum/pressure equations at each time step. This method may avoid the decrease in efficiency induced by iteration. A water analog system was designed and developed to simulate the die casting process. The flow patterns were recorded by a high speed camera with a capturing rate of 500 frames per second. The simulation results were consistent with the experimental ones. Besides, the fluid flow patterns of several components were simulated by the fractional step and VOF algorithm, and the SOLA-VOF algorithm respectively. The simulation results showed that the combination of the fractional step method and VOF method can improve the computational efficiency to some extent in numerical simulation of mold filling process.

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