Need help calculating head
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Toluene is to be transported at a flow rate of 30 cubic meters per hour, over a lift height of 15 meters. The density of the liquid is 0.87, the length of the pipeline is 300 meters, there are 15 elbows, 4 tees, and 3 valves. How should the head pressure be calculated?
Diameter, inlet pressure, outlet pressure
The pipe diameter is unknown for now; the inlet is at atmospheric pressure
For a model with a diameter of 80, a head of 45 meters is quite appropriate.
How is the head of 45 meters calculated?
Is there a simple way to calculate head? Thank you
This post was last edited by bfdlwolf on 2019-6-8 at 22:00. According to \"Pipe Diameter Selection\" (HGT 20570.6-95) or the Guidelines for Pipe Diameter Selection in Petrochemical Process Units (SH/T 3035-2007), the pump outlet diameter was initially determined to be DN80. Under these conditions, the flow velocity was 1.66 m/s, the friction coefficient was 0.02198, and the pressure drop over 100 meters was 32.85 KPa (the viscosity of toluene at 20°C is 0.5866 mPa·s). The pressure loss due to straight pipes was 98.55 KPa, while the local pressure loss was 16 KPa; thus, the total pressure loss was 114.55 KPa. The static pressure drop was 128,02 KPa, and the total pressure drop across the system was 242.57 KPa. The head generated by the pump was 28.45 m; however, a value of 35 m would be more appropriate for this purpose.
Download a Pump Manager app; it contains a small tool for calculating pipe resistance.
There is an approximate estimate. For vertical height, 15 meters corresponds to a head of 15 meters; for horizontal distance, 8 meters is counted as 1 meter of head, so a distance of 300 meters results in a head of 37.5 meters. Elbows, valves, tees, etc. are each counted as 1 meter of head; with 22 of such elements here, the total head is approximately 7 meters. In total, choose a pump with a head of 60 meters. It’s a rough estimate; professional calculation software is needed for an accurate figure.