近净形熔模精铸件蜡模成形规律及压型设计基础的研究

The numerical simulation of flowing field of investment casting wax pattern compacting process is systematically studied in this thesis.In order to make up for the shortage of the research on the wax stock basic properties, the rheological property of the wax stock usually used in investment casting have been tested. On this foundation, the constitutive equation ( viscosity model) was derived which describes the rheological behavior of the wax stock..Based on rheological behavior of the wax stock and on the basis of analysing the affecting factor of the wax stock filling pattern die, the mathematical model was established that describes the process of the wax stock filling pattern die. and then finite difference method(FDM) was adopted to proceed discretization on the established mathematical model and derive its numeric computational format.. According to the derived numeric computational format and the research on the boundary condition、initial condition of wax stock filling model process, SOLA-VOF method was adopted to calculate every field value(velocity field、pressure field and flow region etc.), and numerical simulation system of wax pattern filling model process was developed. the system run on the PC/Windows platform, adopt Visual C++ as developing language, and include three module: preliminary treatment、flowing simulation and aftertreatment. With this system ,we can research the flowing field of wax stock at different space and time, explore the basic regulation of wax stock filling pattern diePhysical simulation device of wax stock filling pattern die was designed. Through physical simulating on the process of wax stock filling pattern die, we compared it with the numerical simulation proceeded in the numerical simulation system , provided reference for the optimization of numerical simulation technology. Finally , the numerical simulation system was applied on the forming process simulate of several wax pattern . It was indicated that the numerical simulation result basically accorded with the practical situation..

用数值模拟和物理模拟相结合的方法研究薄壁大型复杂结构近净形熔模精密铸造蜡模的成形规律和各工艺因素对蜡模质量的影响规律，用全局优化模型研究蜡模成形过程的优化问题，以此为依据形成压型设计的基础理论和支持工具，将压型设计建立在科学理论的基础，使我国的近净熔模铸技术在大型化、复杂化、轻量化和光洁化方面上一个台阶。