Negative pressure issue in centrifugal pump impellers
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The rotation of the centrifugal pump impeller creates a negative pressure area, which causes the medium at the inlet to continuously flow into the impeller. Wouldn’t this lead to the vaporization of the medium and thus cavitation in the pump?
It is certainly possible; the properties of the medium, along with high temperatures, can lead to vaporization and cavitation. One can look at the pump’s net positive suction head and the required net positive suction head definitions.
Appropriate technical measures were put in place during the design to ensure this.
Therefore, a certain filling head should be formed at the pump inlet.
As you described, it generally doesn’t happen; at the initial stage of pump design, the user already provides all the various process parameters for that pump, so such situations basically do not occur. Media that vaporize easily, such as liquefied gas, will increase the pressure in the storage tank to a certain level, providing a constant head at the pump inlet that prevents the medium from vaporizing; I have examples of this.