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New Theories / Re: How do Trees Really lift Water to their Leaves?
« on: 06/05/2008 02:13:58 »
Andrew,
Apologies for my tardiness, been a bit busy as of late, I've been thinking about trees and their ability to lift water for a long time now.
I've been working with my material science students on creating an artificial tree encased in a glass-like sphere to lift water over 300 meters.
Our goal is to take energy from the sun in the form of heat to create electricity. Our basic design involves several of these 'trees' releasing the water they collect at the bottom of their glasslike domes into a central reservoir.Once the reservoir reaches a predetermined level, the water is released, passes through a turbine before being deposited in another reservoir under their 'roots'. This is a complete closed system.
Obviously there has been a lot of interesting problems to overcome!
But one of our biggest problems right now is getting the balance right between evaporation and solute concentration. The evaporation rate from our artificial leaves has to be such that the concentration levels of salt&sugar in our respiratory system don't get too dense and clog up the works!
I posted a question on this in the plant section but with no replies.
With regards to your experiments and whether or not there's a syphon effect I'm of the opinion that you've not created a syphon, as there doesn't seem to be any vacuum involved.
We've yet to test the fluid dynamics of a solute heavy liquid travelling down a 50 meter pipe (nevermind 300meter) into a pure water reservoir (where the pipe's 'skin' is semipermeable) then back up 50 meters.
Would the flow offset the 'osmotic push'?
Would we have fresh water pushing against the downward flow of the solutes?
Or would the two forces combine to provide some additional upward lift?
Your thoughts would be much appreciated.
Blaine
Apologies for my tardiness, been a bit busy as of late, I've been thinking about trees and their ability to lift water for a long time now.
I've been working with my material science students on creating an artificial tree encased in a glass-like sphere to lift water over 300 meters.
Our goal is to take energy from the sun in the form of heat to create electricity. Our basic design involves several of these 'trees' releasing the water they collect at the bottom of their glasslike domes into a central reservoir.Once the reservoir reaches a predetermined level, the water is released, passes through a turbine before being deposited in another reservoir under their 'roots'. This is a complete closed system.
Obviously there has been a lot of interesting problems to overcome!
But one of our biggest problems right now is getting the balance right between evaporation and solute concentration. The evaporation rate from our artificial leaves has to be such that the concentration levels of salt&sugar in our respiratory system don't get too dense and clog up the works!
I posted a question on this in the plant section but with no replies.
With regards to your experiments and whether or not there's a syphon effect I'm of the opinion that you've not created a syphon, as there doesn't seem to be any vacuum involved.
We've yet to test the fluid dynamics of a solute heavy liquid travelling down a 50 meter pipe (nevermind 300meter) into a pure water reservoir (where the pipe's 'skin' is semipermeable) then back up 50 meters.
Would the flow offset the 'osmotic push'?
Would we have fresh water pushing against the downward flow of the solutes?
Or would the two forces combine to provide some additional upward lift?
Your thoughts would be much appreciated.
Blaine