基于ProCAST的大型复杂空心叶片精铸的数值模拟

摘要

重型燃气轮机的叶片尺寸厚大,形状复杂,叶身部位为空心的曲面薄壁结构,铸件极易出现缩孔、疏松缺陷.为改进其工艺方案,利用铸造模拟软件ProCAST对大型复杂空心叶片铸件铸造过程的温度场、流场及固相分数的分布情况进行了模拟,对大型复杂空心叶片的型壳预热温度进行了优化；通过采用980℃的高温型壳预热,实现了大型复杂薄壁叶片的顺利充型.模拟结果预测的缩孔、疏松形成的位置与实际浇注结果十分吻合,采取改进措施后,铸件一次浇注成功,消除了缩孔、疏松缺陷.%Due to large size, thick wall, complex shape and hollow of the heavy duty gas turbine blade, shrinkages and porosity easily appeared in the blade. To optimize the casting process, the liquid flow, temperature field and mushy zone evolution in the large complicated hollow blade were simulated on the basis of casting software ProCAST. The preheating temperature of shell was optimized. By shell preheating at 980 ℃, the large complicated hollow blade was filled soundly. The simulated results of positions of shrinkage and porosity agreed well with the experiment. After the process optimization, a blade without shrinkages and porosity was successfully produced by pouring once.