1988 Fiscal Year Final Research Report Summary
Flow Analysis of Injected Metal in Die Cast
| Project/Area Number |
61550511
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
金属加工(含鋳造)
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| Research Institution | Toyohashi University of Technology |
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Principal Investigator |
NOMURA Hiroyuki Toyohashi University of Technology, 工学部, 教授 (60023272)
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| Project Period (FY) |
1986 – 1988
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| Keywords | Die Cast / Fluid Flow Simulation / Computer Hydrodynamics / 容器内流れ / 流れシミュレーション |
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| Research Abstract |
In order to establish a flow simulator for die cast, model experiments and computer simulations have been done. The experiments are carried out using the mold cavity with plate or box-type obstacles. Through air blow experiments, proper venting arrangement is shown to be important especially near the finally filled area. From the series of water injection experiments, the following results are obtained;
1. Macroscopic behavior of cavity flow is almost the same under the varied conditions of gate speed and vent arrangement for the fixed structure of inner cavity.
2. The area of final filling and combination of different flow lines are formed depending on vent arrangement. These are considered to be closely connected with defects formation in practical die cast.
3. Visualization of cavity filling process has been done by means of oil method and high speed camera pictures. From this, front lines of flow have been decided.
4. In order to predict the characteristics of filling behavior, modelling and numerical simulations are carried out. Navier-Stokes equation is used in the discrete form. The SMAC method (Simplified Marker and Cell method) has been adopted in the simulation. The results explain reasonably the experiments for the two cavity types with plate and box-type obstacles. The location of dead space, final filling area, time change of front lines and flow confluence are predicted well by the simulation.
5. From these results the present mathematical model gives basic ideas for designing a cavity shape with an optimal vent arrangement and suitable gating system.
On the basis of the present study, a die-cast flow simulator will be developed, as an important part of the die-cast CAD system.
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