基于Projection VOF方法的熔模铸造蜡模充型过程数值模拟

Numerical Simulation of Mold Filling ProcessofInvestment Casting Wax PatternBased on Projection VOF Method

针对熔模铸造蜡模充型过程数值模拟软件自主开发,建立了流动场和温度场数学模型,采用Cross-WLF粘度模型描述蜡料的流变性能,基于Projection VOF方法进行蜡料流动过程速度场、压力场以及自由表面的求解。通过试验测量获取了K512型蜡料的热物理性能和流变性能的相关数据,拟合得到粘度模型参数。分别在蜡料常粘度和变粘度模型两种条件下对扳机铸件蜡模充型过程进行模拟,结果表明,所建立蜡模充型过程数学模型能较好地描述蜡料的动态流变特性和传热行为。

Numerical simulation software was independently developed for the filling process of investment casting wax pattern,and mathematical models of flow field and temperature field were established,where the Cross-WLF viscosity model was applied to describe the rheological properties of wax material,based on the Projection VOF method,the velocity field and pressure field and free surface of the flow process of wax are solved.The data of thermal properties and rheological properties of K512 wax were measured by tests,and the parameters of viscosity model were obtained by fitting.The mold filling process of trigger casting wax pattern was simulated under two conditions of constant wax viscosity and variable wax viscosity model respectively.The results show that the established mathematical models of mold filling process of wax pattern can accurately describe the dynamic rheological properties and thermal transmission behavior of wax.