离心力场下铸造充型行为数值模拟

NUMERICAL SIMULATION OFMOLDFILLING BEHAVIORS UNDERCENTRIFUGAL FORCES

建立了离心力场下铸造充型流动的数学模型,采用VC++语言自行编制了离心力场铸造充型及凝固传热的计算机模拟软件。通过模拟旋转圆柱容器中的液体从重力静止水平自由表面状态过渡到离心抛物面自由表面的动态变化过程,并与理论解析曲线对比,以及钛合金薄壁件离心浇注充型状态与试验结果的对比,检验了所建立的理论模型及计算程序的正确性。通过对钛合金薄壁铸件在重力场与离心力场浇注工艺条件下合金熔体充型行为数值模拟结果的对比表明,在一定转速条件下,金属液的离心浇注比重力浇注具有强得多的薄壁充型能力。

A mathematical model for mold-filling processes under centrifugal force conditions is proposed. Computer codes for the centrifugal mold-filling and heat transfer processes are developed using VC++ language. The validity of the computer modeling is examined through comparisons of numerical sample computations on the free surface developments in a rotating cylindrical container with analytical results and that for a partially centrifugal mold-filled titanium casting with experiments. The comparisons between the numerical simulation results from the same titanium mold-filling configuration but under gravity and centrifugal conditions, respectively, show that, at a certain rotating velocity, the alloy melt has a much stronger tendency of mold-filling under the centrifugal condition than under the gravity.