When the outlet flow rate of a centrifugal pump exceeds the rated flow rate, the outlet pressure decreases?
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When the outlet flow rate of a centrifugal pump exceeds its rated value, does the outlet pressure decrease? Is there such a thing? In my opinion, according to Bernoulli’s equation, as long as there is flow through the pump’s outlet valve, even if it is only slightly open, the static pressure energy will be converted into kinetic energy. Therefore, it’s not necessary for the outlet pressure to drop only when the flow rate exceeds the rated value; rather, opening the pump’s outlet valve, regardless of the degree of opening, will result in a decrease in the outlet pressure.
This depends on the performance curve of the pump – whether there is a peak in that curve. If no such peak exists, the pump’s head decreases as the flow rate increases. The presence of a hump leads to an increased lift
This post was last edited by altpage on 2019-6-16 09:34. I agree with the second comment: the performance curves of each pump vary, so it’s not possible to make generalizations; although the flow and head curves of most centrifugal pumps tend to decline over time.
Correct, as long as there is flow, the outlet pressure will decrease to varying degrees. Pressure decreases as flow rate increases. The pressure is highest at zero flow rate; in other words, the pressure is greatest when it is completely closed
It’s usually like this; refer to the pump’s performance curve