In which positions can an impeller be found?

The correct choice highlights the common types of impeller configurations found in various applications. Impellers can be classified into closed, semi-open, and open types based on their design and function.

1. Closed impellers consist of a shroud (covering) on both the inlet and outlet sides. This design allows for maximum efficiency and is ideal for applications requiring higher pressure and flow rates. As the liquid passes through, it gains energy from the rotating blades enclosed within the shroud.

2. Semi-open impellers have an open side on one side, allowing for some solids or entrained air to pass through while still providing a degree of pressure and flow. This type is often used in applications where the material being pumped might contain small solids or where clogging is a concern. It offers a balance between efficiency and the ability to handle particulates.

3. Open impellers have no shrouds and are typically used in applications where the fluid can contain larger solids. This design allows for easier passage of material but at the expense of some pumping efficiency and pressure.

Together, these classifications encapsulate the diversity and functionality of impeller designs in various pumping scenarios. This understanding is crucial for selecting the right impeller type