Gravity Mill - any comments to this idea?

[tbird]

hi free energy,

air filled shuttles will have their problems, but a well designed unit will perform well (think about all the hydraulics at work today).  i think we will be forced to use them simply because of why you want to use a sponge/foam shuttle.  if it's easy to "push back down under water", it won't deliver much work.  if all you want is a small toy or proof of concept, that would be fine (as long as it can be compressed).

i have some thoughts of parts and design, but am not opposed to exploring other suggestions, like ooandioo's.  that's why we have the forum.  many heads are better than one.

hi stepan,

not sure what formulas you are referring to, but most of the figures i used just came from simple math.  this site

http://en.wikipedia.org/wiki/Buoyancy

does have good info about buoyancy we might use at a later date.

as far as changing all the numbers to metric, i think it would be a waste of time, because everytime something is modified, i would have to change the metric numbers too.  what i would suggest is download this Calculator...

http://www.calculator.org/

it's free and does the conversions you would like, as well as a number of other useful things.

after responding to andi's post, i thought of your "U" shaped case.  not sure what type valve you would use, but i think if the top of the "u" were 1 or 2 doors (opening out) that would seal when closed, this could work well.  when it hit bottom, the door(s) would close and latch (from gravity).  at the same time a spring loaded latch would be holding the unit down until enough force (air in container) trips the hold down latch and away it goes.  at the top, the door latch could be triped by a fixed arm.

food for thought.

tbird

[hartiberlin]

What exact formula did you use for the compression of air ?
Thanks.

[tbird]

hi stefan,

"compression of air " is measured in pounds per square inch (psi).  all you need to know is area.  if you want to compress it, just add weight.  divide weight by area=psi.  just basic math.  100 pounds placed on 10 square inches = 10psi.  what ever mass you placed  on it (100lbs.), now has 10psi more applied.  the weight of air at sea level is considered to be 14.7 pounds per square inch (this column goes to outer space).  34 ft in fresh water (33ft in salt water) is considered 1 atmosphere (1 square inch column of water 34 ft deep=14.7psi).  most pressure gauges you see are reading gauge pressure and not Absolute pressure.  the later would be showing the atmosphereic pressure all the time, then add whatever you are checking the pressure of.

wouldn't really call these formulas, mostly just givens.  hope this helps.

tbird

ps  ifound some formulas for you.  look here   http://en.wikipedia.org/wiki/Pressure 

[hartiberlin]

TBird, Okay, thanks for the info.
But how many centimeters or inches must then the swimmer
unit be compressed at what size dimension ?

And how much energy does this use up ?

Maybe someone can post a step by step calculation
of an example with all mathematical steps to calculate that,
so it it getting more clear ?
Many thanks.

[FreeEnergy]

hi free energy,

air filled shuttles will have their problems, but a well designed unit will perform well (think about all the hydraulics at work today).  i think we will be forced to use them simply because of why you want to use a sponge/foam shuttle.  if it's easy to "push back down under water", it won't deliver much work.  if all you want is a small toy or proof of concept, that would be fine (as long as it can be compressed).

i have some thoughts of parts and design, but am not opposed to exploring other suggestions, like ooandioo's.  that's why we have the forum.  many heads are better than one.

hi stepan,

not sure what formulas you are referring to, but most of the figures i used just came from simple math.  this site

http://en.wikipedia.org/wiki/Buoyancy

does have good info about buoyancy we might use at a later date.

as far as changing all the numbers to metric, i think it would be a waste of time, because everytime something is modified, i would have to change the metric numbers too.  what i would suggest is download this Calculator...

http://www.calculator.org/

it's free and does the conversions you would like, as well as a number of other useful things.

after responding to andi's post, i thought of your "U" shaped case.  not sure what type valve you would use, but i think if the top of the "u" were 1 or 2 doors (opening out) that would seal when closed, this could work well.  when it hit bottom, the door(s) would close and latch (from gravity).  at the same time a spring loaded latch would be holding the unit down until enough force (air in container) trips the hold down latch and away it goes.  at the top, the door latch could be triped by a fixed arm.

food for thought.

tbird

you are right.

i also had an idea that might help in this project. the shuttle would be air sealed and in its center would have a one way valve so when it's being pushed down it can recharge the tube/pipe with water. the pipe/tube would be half way in the water. i.e 3 feet in water and 3 feet outside of water in an open tank...this is still half baked idea.