semi-open impeller

例句：

1. 1.The semi-open impeller is a crucial component in the engine's performance.
   半开式叶轮是发动机性能的关键部件。
2. 2.The design of the semi-open impeller has been optimized for efficiency.
   半开式叶轮的设计已被优化以提高效率。
3. 3. The engineers were tasked with designing a new semi-open impeller for the new aircraft.
   工程师们被指派为新飞机设计一个新的半开式叶轮。