What is the difference between cavitation and gas entrapment? What is the principle behind it?
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What is the difference between cavitation and gas entrapment? What is the principle behind it?
There is a very good slide presentation in the PPT section on cavitation and gas entrapment
Gas entrapment occurs when the gas inside the pump is not removed before starting the pump, resulting in insufficient vacuum at the inlet while the pump is rotating and preventing liquid from being drawn in; this generally does not happen with submersible pumps. Cavitation refers to the phenomena that occur during the startup or operation of a pump (when the pump is properly filled with liquid), such as the vaporization of the liquid leading to the formation and collapse of bubbles inside the pump, as well as droplets hitting the impeller.
The answer is upstairs! I’ve learned it; my knowledge has improved!
The Haichuan Forum contains FLASH animations on gas binding and cavitation phenomena； The link is as follows: http://bbs.hcbbs.com/thread-57158-1-1.html
Cavitation refers to the phenomena that occur during the startup or operation of a pump (when the pump is properly filled with liquid), such as the vaporization of the liquid leading to the formation and collapse of bubbles inside the pump, as well as droplets hitting the impeller. In these words, it’s not the droplets hitting the impeller; it should be erosion of the pipe wall
Cavitation refers to the phenomena that occur during the startup or operation of a pump (when the pump is properly filled with liquid), such as the vaporization of the liquid leading to the formation and collapse of bubbles inside the pump, as well as droplets hitting the impeller. In these words, it’s not the droplets hitting the impeller; it should be erosion of the pipe wall
Erosion is mainly caused by the impact of bubbles on the impeller, pump casing, etc., as they accumulate, flow, split, and collapse, coupled with the corrosive effect of dissolved oxygen in the flowing liquid~~
I believe erosion is caused solely by the high-speed flow of fluids and the pressure changes from liquid to gas back to liquid, while impact is merely a superficial phenomenon
But I think I understand what you mean; it’s referring to the same thing
I generally believe that the small pits on the impeller after cavitation are caused by the impact of liquid droplets~~