open impeller

例句：

1. 1.The open impeller is responsible for the efficient operation of the machine.
   开放叶轮负责机器的高效运转。
2. 2. The engineer designed an open impeller to improve the efficiency of the process.
   工程师设计了一个开放的叶轮来提高过程的效率。
3. 3.The open impeller was a significant innovation in the field of mechanical engineering.
   开放的叶轮在机械工程领域是一个重大的创新。