How to solve this math problem
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The density of a certain medium is 700 kg/m3, the temperature is 20°C, and the outlet pressure of the transfer pump is 1.2 Mpa. If the diameter of the horizontal pipeline at the outlet is DN50, what is the maximum flow rate for transporting this fluid in tons per hour? (Pipe resistance is ignored)
By looking at the conditions mentioned by the original poster, it’s clear that they are not a person with a degree in chemistry; since all the conditions weren’t specified, it’s impossible to make any calculations. But then again, if all the conditions are provided, it’s basically possible to calculate it by oneself. It is recommended that the original poster take a look at Bernoulli’s equation.
As mentioned above, the Bernoulli equation is also a waste of effort! Is there really no solution to this problem? ? ? ? ? ? ?
Is the resistance in the outlet pipeline ignored? It can be as big as you want! How can the pump outlet pressure increase without pipeline resistance?
Let the gods answer. . . . . . . . . . . . . . . . . . . . . .
This post was last edited by *ti on 2012-6-25 09:58. Sorry, I feel my previous calculations didn’t take everything into account, so I deleted them
This isn’t really a question. Since it’s the pump’s outlet, you just need to check the head-flow curve of your pump, that is, the H-Q curve, and you’ll know the answer. If you don’t even know that curve for your pump, then obviously you can’t determine the flow rate........
Are the conditions for this problem insufficient? The outlet pressure of a pump isn’t necessarily related to its flow rate; rather, it affects the pump’s head. If calculation is to be done, it can only be done by using the empirical flow velocity based on the pipe diameter
Ah, it’s so troublesome. This isn’t about manufacturing the Shenzhou-9 spacecraft. Generally speaking, unless there are special requirements regarding the manufacturing process, and provided that the medium is not flammable or explosive and its viscosity is not too high, it is advisable to use an economic flow rate of 3 meters per second; a DN50 pipe can transport 21 m³/h； The pump outlet pressure is 1.2 MPa; when the pipeline is not very long, a conservative flow velocity of 5 meters per second can be achieved, and a DN50 pipeline can transport 35 m³/h. But I don’t know what the back pressure in your system is; why choose a pump with a head of 120 meters? In short, the conditions are not complete, so an accurate calculation is impossible. There is no need for precise calculations either; as pipes are used for an extended period of time, their resistance also changes.
There is no solution to this problem. What is the rotation speed of your pump? There’s simply no way of knowing