Flow rate changes in the same tube
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For a pipe with a diameter of 100, there is a section where the diameter reduces to 80. One flow meter is installed vertically at the 100-diameter section, while another flow meter is installed horizontally at the 80-diameter section. Water flows upward from the 100-diameter section over a distance of about 3 meters, and then horizontally through the section with the reduced diameter of 80. Will the flow rate change?
Traffic is continuous; how can there be any changes?
It definitely won’t change; there are errors in the measurements.
Well, for this topic,,, since there is a flow meter, the data measured should be the actual value. I’m not sure what you mean by \"whether the traffic will change\" – which part are you referring to? If it refers to terminal traffic, then it is the actual traffic.
The flow rate remains constant; it is the velocity that changes.
Which location do you mean where the measurement error is smaller?
This post was last edited by Ku Liang Zhi Le on 2020-7-30 09:20. In a pipe without branches, according to the principle of conservation of mass, the mass of fluid flowing through any cross-section is equal, regardless of the diameter of the pipe. For incompressible fluids (liquids), the flow rate (volumetric flow rate, mass flow rate) at any cross-section is the same ； For compressible fluids (gases, vapors), the mass flow rate is the same at any cross-section, but the volume flow rate and weight flow rate can vary; this is related to the fluid density at that cross-section, and the fluid density in turn is related to the temperature and pressure at that cross-section. To obtain the standard-condition flow rate of a compressible fluid, temperature and pressure compensation is required.
If the flow rate changes, then the law of conservation of mass is incorrect. The flow rate remains constant, but the velocity does change.
This post was last edited by HEJIYUER on 2020-7-29 21:18. If it is an exam question, it can be said that it remains unchanged. In the case of engineering problems, there is a \"balance\" relationship between the flow rate in the pipeline and the pressure drop in the pipeline, with the pressure drop including the control valve. And a flow meter is merely an “observer,” not a “controller.”
If the flow rate doesn’t change, then it’s necessary to check whether the flow meter is accurate; this also depends on the straight pipe section and the installation location!