Pump head, flow rate, and the impact of pipe diameter and cavitation! ~
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The pump is a horizontal centrifugal pump with a flow rate of Q=60 m3/H and a head of 40 meters. Medium: Glacial acetic acid with a purity of over 99%, operated intermittently; density: 1050 Kg/m3, viscosity: 1.22 mPa·s (at 20°C); temperature range: up to 90°C and down to 20°C. Steam tracing with copper pipes. NPSHr=0.6 (at rated flow), motor speed: 1475 revolutions per minute. Pump inlet DN100, outlet DN80. The inlet for the user is a DN80 flexible hose (3–4 meters long) that transitions to a DN150 pipe (over 10 meters long), while the outlet is a DN100 pipe that connects to a DN150 pipe (over 100 meters long) leading to the storage tank. The user can change the diameter to match that of the pump’s inlet and outlet. I would like to ask users about the impact of pipes on pump flow rate, head, and NPSH
The impact of the user pipeline on pump flow rate, head, and net positive suction head
Could you explain in detail the impacts? Don’t copy my title, man
Head is used to overcome pipeline resistance; however, if the head is greater than this resistance, the excess head will result in an actual flow rate that is higher than the designed flow rate. As a result, the flow rate of the pump increases. NPSH refers to the excess capacity of the liquid pressure at the pump inlet over the vaporization pressure of the liquid； The cavitation head of the unit refers to the cavitation head determined by the oil pump unit system; its value is determined by the parameters of the pump’s suction pipeline system and the flow rate in the pipes, and it is independent of the pump’s structure.
The user's inlet diameter is DN80, which is smaller than the pump’s inlet diameter of DN100; this results in throttling in the pipeline, causing NPSHe to be less than NPSHr=0.6, and thus cavitation occurs.
It should not affect the pump’s operating condition
The outlet is larger, and there’s also an outlet valve to control the flow rate; this affects the outlet pipeline, but it shouldn’t affect the pump, right?
If the outlet pipeline is large, the pump can achieve a pressure of 40 meters of head; when this pressure acts on a pipe with a DN150 diameter, the pressure should decrease, and it probably won’t reach 40 meters
Could you analyze it in detail? Thank you
Dude, can you give a detailed analysis? Don’t explain the proper nouns
Try simulating it with Aspen