Quote from: LarryC on June 22, 2012, 12:53:59 PM
Thanks, M.
But, It's not hanging right at the bottom, should look like Fig 14. I'll check my specifications.

Regards, Larry

Okay.  Please note that I levitated the Pod so that the gap between it's top surface and the next Riser was the same gap (.31) as all the other gaps.  Just FYI.

M.

Quote from: telecom on June 22, 2012, 12:36:47 PM
Hi Mondrasek,
these spacers on top - I thought all the air should be squeezed out from the top to bring the expansion force to 0?
I'm not by any means an expert in these kind of devices - just asking...
Alex

Hi Alex,

To be honest, I am also not sure.  The buoyancy is the product of the "water head" and the "surface area" of the water displacing Riser's top surface.  So the need for air in the gap due to the spacers does not seem to be necessary.  But I have not tested and really don't know more than that.  Maybe TK or someone else with higher physics understanding can elaborate.  Or possibly someone can do an experiment?

Then again, Mr. Wayne might also answer?

Thanks,

M.

Quote from: neptune on June 22, 2012, 09:48:18 AM
      It is interesting to note that the multilayer systems are based on cylinders of uniform diameter, not tapered cylinders.So if you are building a single layer model, it may be best to use a cylinder of uniform diameter . Any comments ?

With the buoyancy force being the "water head pressure" x "surface area" of the top of a cylindrical "riser", I would think that having tapered walls would change this simple equation into a calculus function.  With a tapered riser, the effective "surface area" would be changing at the different heights of the "water head?"  Just my "swag" at your question.

M.

Not 100% certain, but I think these spacers are shown in the patent.

Quote from: mondrasek on June 21, 2012, 04:47:21 PM

Let me think on this.  It may not matter, like you say.  Could be just my mistake!

@LarryC, I believe you are correct that the outer ring of water can be as big as you want without any negative effects on performance.  In fact, having a bigger ring might change how much pressure difference there needs to be between the ZEDs in a two ZED system in your favor.  But I will need to get back to my own little model and analysis to figure out if that second part is true or not.  And that is not on my schedule for this weekend (which has already started for me!).

Sorry for confusing anyone with my mistake.

M.