重型燃机叶片熔模铸造过程的数值模拟

Numerical Simulation of Investment Casting Large Heavy-duty Gas Turbine Blade

采用Procast软件模拟计算重型燃机叶片熔模铸造过程的温度场,对凝固过程进行了分析,研究了不同的浇注温度对叶片缩松的影响。结果表明,随着浇注温度提高,叶根、叶身处缩松均减少。通过在型壳适当的位置加冷铁、包裹保温棉,可以显著地减少叶片的缩松。对模拟得到的较优工艺进行试验验证,叶片缩松的位置、变化规律与模拟结果相吻合。

The temperature field and solidification field of the gas turbine blade during investment casting process have been simulated by using the Procast software to understand the effects of the pouring tem- perature on the blade porosity. The simulation results indicate that the shrinkage porosities in the blade root and airfoil are reduced with the increase of pouring temperature. The shrinkage porosities are de- creased significantly by placing chiller and insulation cotton on proper location of the mold. Optimized process was presented. Practical experimental results were well in agreement with the simulation ones in shrinkage porosity location and change in the blades.