With the discussion turning to replication and potential materials selections:
A thought that lead to a question, if it doesn't probe too deep.
I haven't dug too deeply into Larry's calculator yet, maybe this answer is there; I'll throw it out anyway.

Selection of suitable tubing sizes for at least the risers ( demo units ) might be easier if... the thickness of the vertical walls of the base can be varied. That's what caused the question: Which is more critical to the successful implementation of the principles ( and maybe the relationship between these 2 is just as important as either independently )...
1. The volume of the air / water contained in the spaces between vessel walls and riser walls.
2. The increase in displacement of the adjacent risers themselves.
IE: Could riser 1 be 2"OD and riser 2 be 2.75"OD if the thickness of the partition separating them was managed to create the appropriate volumes of air and water? Or is that too large a step in displacement?
Dale

It is my understanding that best efficiency is obtained by using thin walls for all risers and lower retaining walls. Like wise the air gaps should be as small as practicable, although not small enough to cause capillary attraction. A cheap material is tinplate [tinplated steel]. It solders easily, but needs a bit of skill to work with. Someone will correct me if I am wrong abot dimensions.

Quote from: wildew on July 26, 2012, 09:59:41 AM
With the discussion turning to replication and potential materials selections:
A thought that lead to a question, if it doesn't probe too deep.
I haven't dug too deeply into Larry's calculator yet, maybe this answer is there; I'll throw it out anyway.

Selection of suitable tubing sizes for at least the risers ( demo units ) might be easier if... the thickness of the vertical walls of the base can be varied. That's what caused the question: Which is more critical to the successful implementation of the principles ( and maybe the relationship between these 2 is just as important as either independently )...
1. The volume of the air / water contained in the spaces between vessel walls and riser walls.
2. The increase in displacement of the adjacent risers themselves.
IE: Could riser 1 be 2"OD and riser 2 be 2.75"OD if the thickness of the partition separating them was managed to create the appropriate volumes of air and water? Or is that too large a step in displacement?
Dale

Dale, I have an older version of a 5 Riser force calculator picture and xls file attached. It uses the 'Riser 5 Diameter Increase' value to account for the clearance and material thickness between the Pod and the closes Riser. With the values set it shows webby1 specification going from 1" Pod to Riser 1 of 2.4", it does not have the retainer wall, so the Increase value would need to be adjusted lower to get webby1 actual Riser 1 size correct.

My newer versions use a 'Clearance' and 'Thickness' value instead, but I don't have any 5 Risers. I can change this one if requested, just PM me.

Regards, Larry

Quote from: wildew on July 26, 2012, 09:59:41 AM
With the discussion turning to replication and potential materials selections:
A thought that lead to a question, if it doesn't probe too deep.
I haven't dug too deeply into Larry's calculator yet, maybe this answer is there; I'll throw it out anyway.

Selection of suitable tubing sizes for at least the risers ( demo units ) might be easier if... the thickness of the vertical walls of the base can be varied. That's what caused the question: Which is more critical to the successful implementation of the principles ( and maybe the relationship between these 2 is just as important as either independently )...
1. The volume of the air / water contained in the spaces between vessel walls and riser walls.
2. The increase in displacement of the adjacent risers themselves.
IE: Could riser 1 be 2"OD and riser 2 be 2.75"OD if the thickness of the partition separating them was managed to create the appropriate volumes of air and water? Or is that too large a step in displacement?
Dale

Hello Dale,
I can not answer definitively on the Small model.

In the large model - we originally built equal layers - thickness and gap, and then we modeled varying the gap - increasing the diameter of the wall thickness is a loss since as the risers move - the air gap above the wall is increased by the wall thickness and the water gap below the riser wall is increased as you stroke - those are minor with thin walls - but thick wall will make a difference.

Also - in our physical testing - you have to allow the air to expand in the system in order to lower the pressure -
If you have too much air in a gap -(by design) you may not be able to move enough to lower the pressure "enough to sink".

Weighting the system can give you a larger range - but you give up some Net to do it.

Here is my point - Sinking is as important as floating - if you plan a 0 to pressure system - and then to Zero again -
That is simple - but you give up efficiency - if you weight the system - you increase efficiency and give up some Net
That is why we suggest the six layer system - it is easy to build and has a nice balance between efficiency and Net.

Lastly - you do not have to match Volumes - equal gaps work almost as well - what you are looking for when matching volumes is to maximize your stroke length - and still Have differential at the last riser.

If you have equal gaps - you will shorten your stroke - in a two Z.E.D system - one side or the other is going up - so stroke length is good - but high Net with short strokes is good too.

I hope this helps 
Wayne
-

Thanks Wayne
LOTS of good info there !
Now I need to go chew and digest a while....
Dale