When a centrifugal pump transports volatile materials, can cavitation and gas entrapment occur simultaneously?
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When a centrifugal pump is used to transport volatile materials, if the pressure at the pump inlet is lower than the saturated vapor pressure of the material, the material will vaporize. In such cases, two things generally happen: 1. If cavitation occurs, will gas entrapment also take place simultaneously? 2. If gas entrapment occurs, will cavitation also occur at the same time? Personally, I think both gas entrapment and cavitation can occur, or rather, they can occur simultaneously. Everyone is welcome to discuss
From a mechanism perspective, air locking is a phenomenon where air remains inside the pump, preventing it from drawing in liquid after startup. If the pump and its suction pipeline system have poor sealing, or if the suction pipe is installed in an inappropriate position, this can result in an excessive amount of air being drawn into the pump. Since air has a very low density, it cannot be expelled to the outer edge of the impeller; as a result, part or all of the flow channels within the impeller become blocked, causing the discharge of fluid to stop. Cavitation is an erosion phenomenon that occurs when the suction height of a pump is too high, causing the pressure inside the pump to equal or fall below the saturated vapor pressure of the liquid being transported. As a result, the liquid vaporizes, bubbles form, and these bubbles burst, leading to what is known as cavitation. From the perspective of the phenomenon occurring: after the \"air binding\" phenomenon takes place, the pump does not discharge any liquid, and there is no noise or vibration. When cavitation occurs, the liquid generates noise and vibration due to the impacts, which reduces the flow rate; in severe cases, no liquid is discharged at all.
I understand the principles of gas binding and cavitation, but when the material pumped vaporizes, does gas binding occur or cavitation? Or do both gas binding and cavitation occur simultaneously?
My understanding is that this is caused by cavitation; in severe cases of cavitation, it should lead to a condition of gas entrapment
Loss of flow is cavitation; when flow is lost, it is air entrapment
First, cavitation occurs; when cavitation becomes severe, air entrapment takes place. This happens because a portion of the liquid continuously turns into saturated steam, resulting in a large amount of steam inside the pump casing. It’s as if the air within the pump casing isn’t properly exhausted, which leads to air entrapment.