Water evaporation-driven toy motor
theguardian.com
Water evaporation-driven toy motor
1–10 of 15 posts
Re: Water evaporation-driven toy motor
#2They're using difference in humidity... wow, inventive.
Re: Water evaporation-driven toy motor
#3Wow this is amazing. I'm actually blown away.
Re: Water evaporation-driven toy motor
#4Aw. Anyone still have a drinking bird?[1] Same principle.
Re: Water evaporation-driven toy motor
#5“(Water)has a desire to evaporate". I wonder what other previously unappreciated emotions it has.
Re: Water evaporation-driven toy motor
#6Aw. Anyone still have a drinking bird?[1] Same principle. [1] https://www.youtube.com/watch?v=Yk71GY02diY
Er... I suppose you could technically consider this an open-cycle heat engine, but I find the connection to the drinking bird pretty strained.
Re: Water evaporation-driven toy motor
#7How much power can these motors produce? Can they be used for practical purposes, or are they simply a cool experiment?
Re: Water evaporation-driven toy motor
#8Aw. Anyone still have a drinking bird?[1] Same principle. [1] https://www.youtube.com/watch?v=Yk71GY02diY
I used to have one, but I lived in a hard water area, and the felt evaporator scaled up and is stopped working.
IIRC a sipping bird is powered by the heat differential caused by cooling of the evaporator. This thing seems to be powered by centre-of-gravity changes caused by motion of hygroscopic material.
I suspect that IRL it would very quickly stop working due to gunk in the water affecting the hygroscopic material, but it's a very neat hack nevertheless.
I wonder if you could build a passive humidifier out of one of these? Float one in a container of (clean) water and attach some fan blades. As it spins, it pushes water into the air. At the very least it'd make a fun executive toy.
Re: Water evaporation-driven toy motor
#9How much power can these motors produce? Can they be used for practical purposes, or are they simply a cool experiment?
The fact they don't give any hard numbers is a pretty big sign that this is nothing more than a neat toy. Powering LEDs takes very little energy - 1 mA at 2V (2 mW) is enough to make it visible. Making it flash reduces that power again.
The concept of using bacterial spores as a means of producing motion is pretty neat, though it's obviously a long way from being practical. The suggested use case (low power remote floating sensors) seems pretty suitable for solar power, which has the advantage of maturity and no moving parts.
Re: Water evaporation-driven toy motor
#10“(Water)has a desire to evaporate". I wonder what other previously unappreciated emotions it has.
Even better, the subtitle reads: "Researchers at New York’s Columbia University harness the element’s natural process"