Large-caliber water meter shells are prone to shrinkage porosity, wrinkles, air entrapment, slag inclusion, and other defects during the lost foam casting process. Taking the vertical spiral wing WS-100 water meter as the research object, through the analysis of the structure of the water meter shell, the flow field and temperature field of the design of outer bottom injection-vertical pouring, outer bottom injection-horizontal pouring and inner bottom injection-horizontal pouring involved in the filling and solidification process are numerically simulated and solve analysis, respectively. The results showed that: when the inner bottom injection-horizontal pouring process was adopted, the filling process of the casting was stable, the isolated liquid phase area of the solidification process was relatively small, and the possibility of forming defects was less. The casting performance is excellent, and the numerical analysis is verified to be effective.

大口径水表壳在消失模铸造过程中容易出现缩孔、皱纹、夹气、夹渣等缺陷。以立式旋翼WS-100水表为研究对象，通过对水表外壳结构、流场和温度场的分析，设计外底注-垂直浇注、外底注-水平浇注对充填凝固过程中涉及的内底注-水平浇注分别进行数值模拟和求解分析。结果表明：采用内底注-水平浇注工艺时，铸件的充型过程稳定，凝固过程的孤立液相面积较小，并且形成缺陷的可能性较小。铸件性能优良，数值分析验证有效。