There is a significant difference between the gas flow rate and the liquid flow rate
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Why is the recommended flow rate for many gases above 10 m/s, while the recommended flow rate for liquids is only between a few tenths and 2 m/s? What is the reason for such a large difference?
Consider various factors such as vibration, noise, and resistance.
Consider various factors such as vibration, noise, and resistance.
The main reason is density; the density of liquids is about 1,000 times that of gases. If the flow velocity of the liquid also reaches over 10 m/s, the kinetic energy of the liquid and the resulting frictional losses will be very high
Same as the answer on floor 4! It’s mainly because the density ratio difference is too large!
It is also necessary to consider whether it is the material flow rate in the main pipeline or the local flow rate within a specific device on the pipeline; for both gas and liquid media, safety risks such as increased vibration and static electricity accumulation resulting from high flow rates must be taken into account.
For gases as well, it’s not necessarily 10 m/s; there is a maximum limit, which mainly depends on the pipe diameter, material, and flow velocity
The main factors to consider are vibration, noise, and resistance; among these, resistance is the most important factor, as it is directly related to pressure drop. A high pressure drop means that more power is required, and more power implies higher energy consumption, which in turn means higher costs. Therefore, these optimal flow rates are also referred to as economic flow rates.