Are the flow rates and wind speeds the same for the main air ducts and the branch ducts?
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The last edit to this post was made by luodanwsk on 2011-9-25 at 17:52. I have a question: there is one main duct running horizontally, from which 10 branch ducts extend out on the sides. When air is supplied, the dimensions of the main duct remain at 800*800, and those of each branch duct remain at 250*250. Given that the wind pressure is sufficient, will the flow rate be the same for each branch duct? Additionally, when drawing in air, the main duct is also 800*800, while the branch ducts are 250*250. Is the air volume and wind speed the same in the branch ducts? In the main duct, is the wind speed highest near the fan, and does it decrease with each additional branch duct? If the size of the main duct is 800*800 and each branch duct is 250*250, then the size of the main duct becomes 760*760; after adding another branch duct of 250*250, the main duct size becomes 720*720. In this way, the size of the main duct gradually decreases. Does the wind speed within the main duct remain constant, regardless of whether its cross-sectional area decreases step by step as described above or stays the same? Are the wind speed and flow rate the same for all 10 branch ducts?
Of course it’s different; the further away a duct is from the supervisor, the lower the air volume flow will be. That’s why regulating valves need to be installed at the air outlets. This relationship has little to do with wind pressure; of course, if the wind pressure is too low, it won’t be possible to deliver air.
No, regardless of the channel used, the pressure drop before and after remains the same; this allows for determining the percentage of flow in each channel, that is, the flow velocity
Theoretically, if identical branch pipes are evenly distributed around the 10 circumferences of the main pipe, the flow velocity in each branch pipe should be the same. However, in practice it is impossible for all ten branch pipes to have the same length, which inevitably leads to uneven flow. Branch pipes with shorter lengths experience less resistance, so their flow velocity is higher and the volume of air flowing through them is greater. The above information is provided for reference only
The flow rate of each branch is related to its respective flow resistance; in an extreme case, if a branch is completely blocked, there will be no flow at all!
This post was last edited by li*ch1968 on 2012-4-19 at 19:01. No, regardless of the channel used, the pressure drop before and after remains the same; this allows for determining the percentage of flow in each channel, that is, the flow velocity.
The air volume will definitely be different, but the resistance will definitely be the same. :):)
A classic question: when air is supplied, the static pressure difference allows for a clear analysis of the distribution of air volume.