Does the temperature of the medium at the pump inlet affect the flow rate at the pump outlet?
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We have a multi-stage centrifugal pump A here; the inlet pressure is 7.2 kilograms per square centimeter while the outlet pressure is 62 kilograms per square centimeter. Initially, the feed temperature was 80 degrees Celsius, and the outlet flow rate fluctuated frequently. After raising the feed temperature to 88 degrees Celsius, the outlet flow rate became very stable. The inlet of pump A is connected to the outlet of another pump, B. The outlet pressure of pump A remains stable throughout – why is that? Seeking guidance, thank you! :)
Are there any other changes in operating conditions? Logically, there shouldn’t be
Let’s see if there is any change in the actual flow rate after heating Logically, at a temperature of 8°C, if the mass remains constant, the volumetric flow rate should not change. Fluctuations in outlet pressure are usually due to low flow rates
What medium? That doesn’t make sense
I find it strange anyway; I checked and found that the required operating temperature for Pump A is 85. Additionally, the inlet of Pump B is connected to the product tank at the top of the vacuum tower. Could it be that non-condensable gases from the liquid phase get into the pump, and due to the high temperature, these non-condensable gases cannot accumulate in the product tank and are thus drawn away by the vacuum system? Or has the viscosity of the material changed? Anyway, the export traffic has been quite stable these days; before, it was often underreported and manual control was required :)
As the temperature of the fluid decreases, the hydraulic efficiency increases (with viscosity remaining roughly constant). A lower temperature results in an increase in NPSHa, which also has a significant impact on the stability of the pump
Did you add a heating pipeline or a heat pump to raise the temperature? If the medium is viscous or prone to crystallization and solidification, it will affect the flow rate of the medium, thereby impacting the stability of the flow. First, determine what the medium is, and then look at its freezing point in order to make a judgment; the way the question is phrased can easily confuse people. If it’s due to the medium, it is recommended that you use a pump with a jacket, which will solve your temperature control problem. Moreover, from your description, it seems that pumps A and B are connected in series; if they are in series, this indicates that you require a higher head.