Quote from: see3d on August 15, 2012, 12:11:54 AM

Hello all,

This is the link to my public ZED distribution folder:

https://www.dropbox.com/sh/6vdnbk72ywyckns/zB501rT78P

A PDF document has just been uploaded.  It is too late tonight to generate a set of animation files.  That will have to wait until sometime tomorrow.  Text that appears in red are numbers and formula terms that are changed from my previous version.  They will only be red for a single significant version.

The purpose of this analysis is to present (for critical review), the theory and implementation I used for a simplified simulation of a single ZED machine. This is just a single layer version.  A 2+ layer simulation model will follow after this one is verified for accuracy.  No attempt was made to find the most efficient geometry for this.  It is known that other geometries had better simulation results, but it would be wasted effort to try to optimize this model before verifying that it is accurate.

~Dennis

Thanks Dennis !

EDIT:

What sim program did you use Dennis ?

I'm used to talking of force as Newton's rather than pounds - in fact, using SI units because they are a coherent system.

I use WM - if I have time I will replicate a similar system to what you have shown, in WM [time is limited] - I am fairly confident that I can mathematically create the pseudo/faux forces required that will act exactly the same as real buoyancy force so that the sim is an accurate predictive tool.

P.S. I for one appreciate & understand the enormous amount of thought, time & effort you have put into this sim & presentation.

Quote from: fletcher on August 15, 2012, 04:38:55 AM
Thanks Dennis !

EDIT:

What sim program did you use Dennis ?

I'm used to talking of force as Newton's rather than pounds - in fact, using SI units because they are a coherent system.

I use WM - if I have time I will replicate a similar system to what you have shown, in WM [time is limited] - I am fairly confident that I can mathematically create the pseudo/faux forces required that will act exactly the same as real buoyancy force so that the sim is an accurate predictive tool.

P.S. I for one appreciate & understand the enormous amount of thought, time & effort you have put into this sim & presentation.

Thanks Fletcher,
It can take more time and effort to build a good sim than a physical model.  However. it is orders of magnitude less work to make a change and optimize it for a build. 

I have been doing engineering work in pounds and inches since before there was any push to include metric in this country.  Using units I am used to keeps me from making stupid errors.  Also, since this is a mixed weight (gravity) and force system, I decided to do everything in the same weight measure for force to keep all units the same.  Just my personal choice, and some non-engineers may be able to follow better this way.

This sim was written in AmiBroker.  It is a stock market analysis program.  It had the most useful characteristics for writing the UI stuff I needed of any program I was familiar with. The language is "C" like.

Quote from: TinselKoala on August 14, 2012, 11:27:56 PM
Well, OK, then.... I guess we all agree that the Work, or equivalently the Energy... of the three systems LarryC presented are not the same and there isn't any magic happening. The fact that the "head pressures" are logically the same in all three cases is the Red Herring of the week. Pressure is not energy, it is not work, it is NOT a conserved quantity.

So I am afraid I don't get the point. Reduced work IN for the same pressure -- and reduced work OUT -- , with no other considerations deemed important?

https://www.youtube.com/watch?v=pTSMyKdKDR0

Well I guess I assume too much if I think that Larry's post made a clear point.  It is clear to me probably only because of all the diagrams and calcs I've done on this system.

Let me try to explain a different way:

First, the diagrams that Larry showed are only a good explanation for the INPUT side of the ZED work analysis.

The OUTPUT side of a ZED is not drawn at all.  But please consider that the analysis of the Output system needs for you to consider the amount of buoyant force that can be produced by a given Head of water.  And then the distance that this buoyant force can work over (stroke) to create the Output work for comparison with the Input work.

It is agreed that the Input work of the single U system (left side) that Larry illustrated in post #1376 is greater (edited) than the Input work of the 3U system (right side).  However, the water Head pressure created and therefore the buoyant force *potential* of the two systems are the same.  Stroke height potential is not equal, just the buoyant force potential.

In the classical Archimedes float setup or the single U system it is known that the Input work only produces (at most) an equal and opposite Output buoyancy force potential.  I believe this is the explanation why a buoyancy device cannot be OU.  So Work In = Work Out.

But in the 3U system we have now reduced the Input work to achieve the *same* Output buoyancy force potential as the classical examples.  So Work In < Work Out is a possibility.  The next step would be to find a way to capture the Work Output while in this unbalanced condition?

M.

This was sent to me to post by someone who wishes to remain anonymous for the moment.  FWIW:

This is nothing to do with how much force, just force flow.

If fluid under pressure is moved into the pod chamber the risers will rise.

If the risers are not allowed to rise then that fluid under pressure
will move the air and water columns within the risers and ring walls.

The changed air and water columns store that input value and can return
it at any time.

If fluid under pressure is continued to be moved into the pod chamber
and the resistance against the risers is maintained as such to just
allow the risers to lift but make no further change in the air and water
columns, then I can extract that resistance value.

If at the top of the lift the risers are held in place and the pressure
against the fluid in the pod chamber is reduced then the stored
potential in the air and water columns within the risers can be extracted.

The fluid under pressure can be manifested by raising a reservoir of
fluid a distance.

Quote from: see3d on August 15, 2012, 12:11:54 AM
Hello all,

This is the link to my public ZED distribution folder:

https://www.dropbox.com/sh/6vdnbk72ywyckns/zB501rT78P

A PDF document has just been uploaded.  It is too late tonight to generate a set of animation files.  That will have to wait until sometime tomorrow.  Text that appears in red are numbers and formula terms that are changed from my previous version.  They will only be red for a single significant version.

The purpose of this analysis is to present (for critical review), the theory and implementation I used for a simplified simulation of a single ZED machine. This is just a single layer version.  A 2+ layer simulation model will follow after this one is verified for accuracy.  No attempt was made to find the most efficient geometry for this.  It is known that other geometries had better simulation results, but it would be wasted effort to try to optimize this model before verifying that it is accurate.

~Dennis

BRAVO!
Dennis - Your buoyancy simulation model is so well thought out and detailed! It is beautifully coded.
I like the way the split screen lets you compare water and air levels to the at-rest model at the same time.

The document has a good flow for all levels of readers. The engineers should be happy with all of the details in the formula pages yet the non-engineer can follow the detailed conceptual descriptions, graphs and animated models.
I agree with all of your conclusions on the last page.

LET'S GIVE DENNIS SOME FEEDBACK so we can move ahead to the multi-layered versions!