Difference between revisions of "Talk:2775: Siphon"

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Agree, capillary action does not seem to be referenced or implied in the comic, presenting only the (not "functioning") siphon phenomenon.
 
Agree, capillary action does not seem to be referenced or implied in the comic, presenting only the (not "functioning") siphon phenomenon.
:Seconded/thirded. Capillary action isn't even what they were expecting. The small amount of water in the lowe receptical indicates they correctly 'filled'' the tube, but then as the longer length drained it did not then induce further flow up and over through the shorter length. e.g. nature no longer abhored the resulting vacuum (or there was increased negative-pressure vapourisation, beyond that previously expected, or other method of seepage 'airlock'-breaking) and thus the short-end also drained straight back out again instead of becoming a potentially self-sustaining inflow to the whole siphoning setup.
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:Seconded/thirded. Capillary action isn't even what they were expecting. The small amount of water in the lowe receptical indicates they correctly ''filled'' the tube, but then as the longer length drained it did not then induce further flow up and over through the shorter length. e.g. nature no longer abhored the resulting vacuum (or there was increased negative-pressure vapourisation, beyond that previously expected, or other method of seepage 'airlock'-breaking) and thus the short-end also drained straight back out again instead of becoming a potentially self-sustaining inflow to the whole siphoning setup.
 
:While the capilliary action element ''could'' induce the start of a rather limited 'empty' siphon setup to start (maybe, I'd have doubts about the 'fluid friction' actually acting against the gravity-feed part, once the surface-tension bit has "climbed the mountain" and started to merely seep out of the other end, almost incidentally, for a sufficiently thin tubing where CA is a significant factor), this suddenly failing for whatever reason (surface-tension effects being nullified) wouldn't then send a token amount of water into the low bucket, nor particularly stop unrelated siphon-flow from continuing properly (in fact, suddenly 'interaction-free' liquid and tubing might siphon ''faster'', with effectively zero fluid boundary effects dragging on the induced flow).
 
:While the capilliary action element ''could'' induce the start of a rather limited 'empty' siphon setup to start (maybe, I'd have doubts about the 'fluid friction' actually acting against the gravity-feed part, once the surface-tension bit has "climbed the mountain" and started to merely seep out of the other end, almost incidentally, for a sufficiently thin tubing where CA is a significant factor), this suddenly failing for whatever reason (surface-tension effects being nullified) wouldn't then send a token amount of water into the low bucket, nor particularly stop unrelated siphon-flow from continuing properly (in fact, suddenly 'interaction-free' liquid and tubing might siphon ''faster'', with effectively zero fluid boundary effects dragging on the induced flow).
 
:But perhaps someone with more QFD experience could explain where my assessment is wrong. So not going to personally rewrite the current Explanation intro just now. [[Special:Contributions/172.70.162.161|172.70.162.161]] 16:21, 12 May 2023 (UTC)
 
:But perhaps someone with more QFD experience could explain where my assessment is wrong. So not going to personally rewrite the current Explanation intro just now. [[Special:Contributions/172.70.162.161|172.70.162.161]] 16:21, 12 May 2023 (UTC)

Revision as of 16:23, 12 May 2023

My understanding was that siphoning can essentially be explained by the Bernoulli equation? There is a difference in potential energy between the upper and lower container so it flows. The weight of water in the downhill part of the tube pulls water up the uphill section of the tube (think like a vacuum), and so on until there's either no difference in head or no more water. Siphoning will work with any diameter tube. 172.70.91.151 15:43, 12 May 2023 (UTC)

That's right. The only mention of capillary action in the siphon wikipedia article is when talking about phenomenon that *isn't* a siphon. Barmar (talk) 16:15, 12 May 2023 (UTC)

Agree, capillary action does not seem to be referenced or implied in the comic, presenting only the (not "functioning") siphon phenomenon.

Seconded/thirded. Capillary action isn't even what they were expecting. The small amount of water in the lowe receptical indicates they correctly filled the tube, but then as the longer length drained it did not then induce further flow up and over through the shorter length. e.g. nature no longer abhored the resulting vacuum (or there was increased negative-pressure vapourisation, beyond that previously expected, or other method of seepage 'airlock'-breaking) and thus the short-end also drained straight back out again instead of becoming a potentially self-sustaining inflow to the whole siphoning setup.
While the capilliary action element could induce the start of a rather limited 'empty' siphon setup to start (maybe, I'd have doubts about the 'fluid friction' actually acting against the gravity-feed part, once the surface-tension bit has "climbed the mountain" and started to merely seep out of the other end, almost incidentally, for a sufficiently thin tubing where CA is a significant factor), this suddenly failing for whatever reason (surface-tension effects being nullified) wouldn't then send a token amount of water into the low bucket, nor particularly stop unrelated siphon-flow from continuing properly (in fact, suddenly 'interaction-free' liquid and tubing might siphon faster, with effectively zero fluid boundary effects dragging on the induced flow).
But perhaps someone with more QFD experience could explain where my assessment is wrong. So not going to personally rewrite the current Explanation intro just now. 172.70.162.161 16:21, 12 May 2023 (UTC)