Can flow rate be determined knowing the pipe diameter and pressure?
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Knowing the pipe diameter and pressure, can we determine the flow rate? For a pipe diameter of 250 and a pressure of 1.6, can we roughly estimate what the flow rate per unit time is?
The calculation formula is as follows: Q = 0.25kπD*D*√2gH. Here, k is the discharge coefficient; values for this parameter can be found in relevant hydraulics references. π represents 3.14. D is the nominal diameter of the pipe in meters. g is the acceleration due to gravity, measured in kilograms per meter per second squared. H is the water pressure in MPa. Q represents the flow rate in tons per hour. The above formula was derived by me for reference purposes only. I’m not sure if it’s correct
Refer to the \"SHT 3035-2007 Guidelines for Selecting Pipe Sizes in Process Units of Petrochemical Enterprises\", select an appropriate pressure drop per 100 meters; this allows for the calculation of the normal flow velocity and thus the flow rate.
This post was last edited by qugd on 2012-9-1 19:57. It is impossible to calculate the flow rate based solely on diameter and pressure. A simple example can illustrate this: a high-pressure gas cylinder with a pressure of around 15 MPa, and a large diameter of about 300 millimeters, yet the flow rate of the gas inside the cylinder is zero. To calculate the flow rate of liquid in a pipe, a necessary condition exists: a pressure difference. This is because a pressure difference is essential for generating flow; it is the existence of such a pressure difference (a difference in potential energy) that enables the medium to move from high pressure to low pressure, thereby acquiring kinetic energy.
Definitely not; if the pressure drop is known, it’s still logical
If pressure is replaced with pressure difference, how should it be calculated?
It is only known that pressure and pipe diameter cannot be used to accurately calculate flow rate. Even if the medium is known, only a flow velocity can be estimated, resulting in a very broad range for the calculated flow rate.
My personal understanding is that the flow rate can be determined using the pressure difference, and from that the flow volume can be calculated.