Gravity Mill - any comments to this idea?

[prajna]

No Stefan.

I said: 100 Liter = 100 Kg in the main pipe and 10 kg= 10 Liter in the exit pipe.

Would the shuttle see 110 Kg or 200 Kg ontop of it ?

The shuttle will only see the 10 litres in the exit pipe.

@ tbird
Let's calcuate everything based on 10m depth to begin with and then when the model is validated we can change whatever we like.

To lift 1kg up 1m we have to have a displacement size of 1 litre.  So long as the reservoir volume is the same as its weight then it will be boyancy neutral and doesn't need to affect our calculations (it wouldn't sink but we are adding 2 litres of compressed air to it so that will make it do so.)

I'll work on a calculator applet for these things so that you can put in any figures you like.  Ok?

[hartiberlin]

Okay, looking forward to your applet.
I could integrate it here into a posting, if you would send me the HTML code
via email.
Me as the admin has rights to include HTML code into the postings.

Anyway, yes , we have to find dimensions of this gravity mill,
so that we can build it also in smaller  space and smaller height.

Maybe we can find parameters, where one only needs a height of 1 Meter for the main
pipe and water tank and the exit pipe is another 1 Meter, so 2 Meter height will be okay ?

Also it would be good, if one could use something like these water column bubblers:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=4415427510


If we can modify one of these to build such a gravity mill, it would be very easy to get these
water columns.

[tbird]

hi guys,

i had to take a breather.  my breath of fresh air came from page 6&7 of Mr. Herrings drawings.

http://www.icestuff.com/energy/elsa/

boyle's law is what you need to study to figure out the correct pressure.  see here

http://www.grc.nasa.gov/WWW/K-12/airplane/boyle.html

i attached a paint drawing (not very good) to show how a shuttle design could start (more details later).  the black part at the bottom and the rest of the container can weigh 1.5 times as much as it displaces.  not sure what material would work, but lots of stuff heavier than water, but don't know if anything weighes that much in that little volume.  this might be a slight flaw with Mr. Herrings example.  the worse result is a higher compression like you guys were trying to use or less buoyancy for a given displacement.  the shuttle on the left is in the compressed mode with 2 bar (30psi+or-). that's the white part inside the shuttle.  since pressure and volume are an exact ratio, if we reduce the pressure by half, the volume will double.  the picture to the right shows this state.  not sure if you can tell from the drawing but that is suppose to be twice what it was in the compressed state.  since the outside water pressure is the same at 1 bar, the shuttle would not expand any more at this depth.  if the retainers at the top of the shuttle walls  were not there and the walls extended up, as the shuttle went up, the air inside would expand the volume further.  but it is there so when the shuttle reaches the surface, there will still be 1 bar (15psi+or-) inside.

i modified the drawing after i attached, so not sure which will show up.  if the wrong one comes, i quickly send the other.

well that didn't work at all.  stefan what am i doing wrong?  changed to gif and still doesn't like it.

[tbird]

hi all,

just emailed it to stefan.  maybe he can post it.

tbird

[prajna]

tbird, if you double the volume then you also double the amount of water you displace and increase the bouyancy so must increase the weight to match.  If you increase the pressure then you can use less weight and less volume.

Still working on the calculations.