semi-enclosed impeller

例句：

1. 1.The new semi-enclosed impeller significantly improved the efficiency of the machine.
   新的半封闭叶轮大大提高了机器的效率。
2. 2. The design of this semi-enclosed impeller is innovative and practical.
   这种半封闭叶轮的设计既创新又实用。
3. 3. The engineers carefully designed the semi-enclosed impeller to ensure its stability and durability.
   工程师们仔细设计了半封闭叶轮，以确保其稳定性和耐用性。