Equalizing air flow into long slitted tube?
Equalizing air flow into long slitted tube?
(OP)
Assume a 10" diameter 10' long tube or pipe laying horizontally with a 2" wide slit all along its top side running it's full length.
One end is capped and the other has a fan drawing air into the pipe through this 2" slit all along its length.
Without changing the slit dimensions, is there anything about the tube diameter itself, if that could be varied along its length, that would then help have air being drawn in all along the slit be more equalized and not mostly just coming in through the slit nearest the end with the fan?
IOW's, if you wanted it to draw in near to the same volume of air at one end of slit compared to other end, is there anything about changing pipe dimensions make any difference?
Thanks for any thoughts.
One end is capped and the other has a fan drawing air into the pipe through this 2" slit all along its length.
Without changing the slit dimensions, is there anything about the tube diameter itself, if that could be varied along its length, that would then help have air being drawn in all along the slit be more equalized and not mostly just coming in through the slit nearest the end with the fan?
IOW's, if you wanted it to draw in near to the same volume of air at one end of slit compared to other end, is there anything about changing pipe dimensions make any difference?
Thanks for any thoughts.





RE: Equalizing air flow into long slitted tube?
The only factors that determine how much air flows through any portion of the slit is the slit width (or geometry), which you say must stay constant, and the pressure difference across the slit at any point. So, to stay constant anywhere along the slit length, there can be no pressure gradient along your tube, which means little or no flow along the tube.
To do what you are asking, the slit must have a relatively high resistance to air flow compared to all other parts of your system.
RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
B.E.
You are judged not by what you know, but by what you can do.
RE: Equalizing air flow into long slitted tube?
At 10'length it really should be easy, at least better than a balancer would do. And even if each foot has slightly different flowrate - it probably won't matter.
RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
drawing from multiple points also helps.
B.E.
You are judged not by what you know, but by what you can do.
RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
might could be done upstream of the slot if it has to stay same width all along its length.
RE: Equalizing air flow into long slitted tube?
Remember - More details = better answers
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RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
RE: Equalizing air flow into long slitted tube?
and will play with restricting the size of those channel openings, more on the fan end than the closed end to achieve more
uniform draw into the tube all along its full length.
Basically accomplishing same as having 2" slit be less wide at fan end drawing air in, and ever wider the further away.
RE: Equalizing air flow into long slitted tube?
https://res.cloudinary.com/engineering-com/image/upload/v1493392098/tips/VAC_jxordi.pdf