positive displacement flow meter

例句：

1. 1. This type of flow meter is used to measure the positive displacement of fluids.
   这种流量计用于测量流体的正位移。
2. 2.The positive displacement flow meter is a reliable tool for measuring the volume of liquids.
   正位移流量计是一种可靠的工具，用于测量液体的体积。
3. 3.The positive displacement flow meter was designed to detect leaks in pipelines.
   正位移流量计被设计用来检测管道中的泄漏。