The debate over the mechanisms responsible for the flow rates of simple tube siphons (Fig. 1) has received much attention in the physics education and general physics literature in the past decade. Particularly with regard to the driving mechanism for water siphons, some suggested explanations emphasize contributions, or lack thereof, from the atmospheric pressure on the tank supply-side, while other sources argue for, and against, the pulling effect of the weight of the water in the long side of the siphon, in a chain-like action via intermolecular forces, as the dominant mechanism driving the siphoning action. What is more, the atmospheric model has recently become the principal competitor to the chain pulling model, neither of which in our assessment supplies the essential explanation of the dominant driving mechanism of simple tube siphons, nor in any way accounts for their near steady-state flow rates.
References
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2.
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We identify normal water tube siphon operation as having ambient pressures of 0.5 atm or greater throughout, which allows for a siphon height above the supply tank of 5 m at sea level. Note that water siphons do indeed operate continuously under more exotic pressure conditions, particularly at or below the edge of the HDL phase transaction (see Ref. 5 discussion). An example of such water siphon behavior is reported in
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2018
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