Quote from: fletcher on September 17, 2012, 04:19:01 PM
TK .. a few here at this thread [they know who they are & thankyou] have taken the time to build something [real or sim] & report their findings to the forum, either good or bad - you are also part of that small group, willing to explore the concepts of a ZED or a dual ZED to establish facts rather than beliefs, delusions, hopes or desires - in short to dispense with distractions & let the chips fall where they may.

I think we can only rely on the goodwill of those few people to get to the bottom of Mr Wayne's claims - others have different agenda's that don't necessarily fit with discussing their findings or facts here, that is obvious - though I'll wager that they are not adverse to reading thru the thread for information that might be useful.

All that has been established here so far will aid see3d in calibrating his sim for a single layer ZED analog - when that is reliable & accurate he can build multi layer versions with performance confidence - this can be checked against real world builds in a feed back loop & save the builders time, effort & money - that has to be a good thing.


Yes we need to be thankful to those who are building and sharing. Regarding having a different agenda, it is quite possible that some replicaters are focused on the prize money, and that it their reason for not sharing. Whenever money rears its ugly head, there are problems, that it is the way of the world.
@TK. Yes it would be wonderful if this was totally open source, but surely, the current situation is better than nothing?

Hi guys,

I too have had a go with an Excel spreadsheet. Looking over what's been posted by Fletcher's PE calculation images and MT's spreadsheet, I think this looks pretty good. However the proof of the pudding is in the eating, so hopefully some of you guys will give it a once over and let me know your thoughts.

I've tried to set it up in a way that allows for easy to see modifications (highlighted by the green cells), to change the size of the pod and tanks, the pod density and the height to which the water should be filled to (if you don't want the pod completely submerged), which should then calculate everything else.

I think that the only question really is the formula used for Buoyancy Work. I played around with finding actual work potential at certain pod submerged depths and plugged those in to an equation calculator. That gave me the one I've used, which, looking at Fletcher's PE information and sizes used in his images, gave me a total buoyancy work in the right ball park. Overall the buoyancy never overhauls the energy requirement of the fill but the over all cycle does appear to make it.

Currently setup:
  Work In: 107.32 J
  Work Out: Up: 72.21  Down: 56.96  Total: 129.17 J

  Net: +21.85 J less the various losses.

This seems at first sight to support a comment I'm sure I saw Wayne make once (I haven't looked back through the whole thread, and it's not easily searchable, so happy to be corrected), that in it's most basic form the ZED idea was barely over unity.

Current todo list includes: Having more water input to sustain buoyancy force to see if that improves things, modification of the stroke height, adjustment of tanks relative to each other, and ultimately, more layers!

Please let me know what you guys think, and I'm happy to be told where I've gone wrong!

Note: There is a macro in the spreadsheet, I added a chart for a visual element, so if you don't wish to allow macros to run from a stranger, who could blame you, then make sure you click no/don't run/remove at the prompt. The overall spreadsheet will still work, but the chart wont.

Cheers
Amo

This is from my notes. I did not record the reply number and page.


3 Layers, just overunity
4 Layers, not much better.
6 Layers, using two Zeds 250%
or 190% with one Zed.


Remember that with more layers come more set-up problems, and that I believe mrwayne recommended not more than 4 layers for a table top model.
To me, all this implies that the real OU is in recycling the exhaust as Webby1 says.

Quote from: AmoLago on September 18, 2012, 08:03:08 AM

Hi guys,

I too have had a go with an Excel spreadsheet. Looking over what's been posted by Fletcher's PE calculation images and MT's spreadsheet, I think this looks pretty good. However the proof of the pudding is in the eating, so hopefully some of you guys will give it a once over and let me know your thoughts.

I've tried to set it up in a way that allows for easy to see modifications (highlighted by the green cells), to change the size of the pod and tanks, the pod density and the height to which the water should be filled to (if you don't want the pod completely submerged), which should then calculate everything else.

I think that the only question really is the formula used for Buoyancy Work. I played around with finding actual work potential at certain pod submerged depths and plugged those in to an equation calculator. That gave me the one I've used, which, looking at Fletcher's PE information and sizes used in his images, gave me a total buoyancy work in the right ball park. Overall the buoyancy never overhauls the energy requirement of the fill but the over all cycle does appear to make it.

Currently setup:
  Work In: 107.32 J
  Work Out: Up: 72.21  Down: 56.96  Total: 129.17 J

  Net: +21.85 J less the various losses.

This seems at first sight to support a comment I'm sure I saw Wayne make once (I haven't looked back through the whole thread, and it's not easily searchable, so happy to be corrected), that in it's most basic form the ZED idea was barely over unity.

Current todo list includes: Having more water input to sustain buoyancy force to see if that improves things, modification of the stroke height, adjustment of tanks relative to each other, and ultimately, more layers!

Please let me know what you guys think, and I'm happy to be told where I've gone wrong!

Note: There is a macro in the spreadsheet, I added a chart for a visual element, so if you don't wish to allow macros to run from a stranger, who could blame you, then make sure you click no/don't run/remove at the prompt. The overall spreadsheet will still work, but the chart wont.

Cheers
Amo

Hi .. I'm out here for a few days so don't have time to go thru your spreadsheet carefully, especially a closer look at your output formula - I do like the presentation though :7)

What I suggest you do is add some CHECK cells into the analysis [I do this as a cross reference from a different perspective] - sometimes you can get carried away pumping out formula's that you loose sight of what you are actually trying to say with those formula's.

For instance, obviously buoyancy is generated when there is water beneath the pod & the first diagram should show some because you are using the floatation law to find neutral buoyancy & where the height of water must be to achieve that - that's just a minor presentation point & I haven't checked whether that extra height is built into your inputs - also m^3 should be kg in some cells.

Buoyancy itself is a force - it is the VOLUME of displaced water [in this case the volume up the sides of the Pod] - it can be viewed as the negative gravity effect of that MASS/VOLUME of water - not virtual water but real water to find energy/work capacity- you need to know the height the water is raised, find its COM [half height raised], apply 'g' & you have the PE raising ability of that volume of water aka buoyancy.

Then you need to find the Apparent Weight of the Pod - gravity is still pulling this down - deduct it & if any force is left over it is the Net Upthrust force which does the Work, IINM.

If you include a check cell near your buoyancy work formula & approach it from the simple mathematics described above you can compare it to your result to see if they line up - if not one or other is likely wrong or needs a closer look - you're just looking at the problem from another angle to compare the results.

Just My Opinions [JMO's] at short notice - you may already have approached it this way but I didn't have time to go thru carefully.

P.S. a simple test anyone can do while doing the dishes - take a light weight plastic glass - depress it & feel the upthrust force - fill it with water - turn it over then lift it out of the water upside down until the rim almost breaks the surface - feel the weight of that water [a bit like a barometer tube] - that is similar to the Upthrust force of the glass depressed down into the water pushing back up - it gives you some perspective & an idea of the forces we are talking about & how you can viewed it as volume/mass PE gains or losses for analysis purposes.

Quote from: fletcher on September 18, 2012, 06:34:06 PM
Hi .. I'm out here for a few days so don't have time to go thru your spreadsheet carefully, especially a closer look at your output formula - I do like the presentation though :7)

What I suggest you do is add some CHECK cells into the analysis [I do this as a cross reference from a different perspective] - sometimes you can get carried away pumping out formula's that you loose sight of what you are actually trying to say with those formula's.

Thanks for the idea, I'll add adding some checks on to my todo list.

Quote from: fletcher on September 18, 2012, 06:34:06 PM
For instance, obviously buoyancy is generated when there is water beneath the pod & the first diagram should show some because you are using the floatation law to find neutral buoyancy & where the height of water must be to achieve that - that's just a minor presentation point & I haven't checked whether that extra height is built into your inputs - also m^3 should be kg in some cells.

Yeah, I like that idea too. I think I'll add a sheet dedicated to diagramming the steps the pod is going through. This will probably work nicely with the checks I'll add.

Quote from: fletcher on September 18, 2012, 06:34:06 PM
Buoyancy itself is a force - it is the VOLUME of displaced water [in this case the volume up the sides of the Pod] - it can be viewed as the negative gravity effect of that MASS/VOLUME of water - not virtual water but real water to find energy/work capacity- you need to know the height the water is raised, find its COM [half height raised], apply 'g' & you have the PE raising ability of that volume of water aka buoyancy.

Then you need to find the Apparent Weight of the Pod - gravity is still pulling this down - deduct it & if any force is left over it is the Net Upthrust force which does the Work, IINM.

If you include a check cell near your buoyancy work formula & approach it from the simple mathematics described above you can compare it to your result to see if they line up - if not one or other is likely wrong or needs a closer look - you're just looking at the problem from another angle to compare the results.

Err... I'll need to read that a few more times to make sure I understand what your saying there. It seems to make sense, but I'm at work at the mo, so I can't put my full attention on this.

Quote from: fletcher on September 18, 2012, 06:34:06 PM
P.S. a simple test anyone can do while doing the dishes - take a light weight plastic glass - depress it & feel the upthrust force - fill it with water - turn it over then lift it out of the water upside down until the rim almost breaks the surface - feel the weight of that water [a bit like a barometer tube] - that is similar to the Upthrust force of the glass depressed down into the water pushing back up - it gives you some perspective & an idea of the forces we are talking about & how you can viewed it as volume/mass PE gains or losses for analysis purposes.

This I think, from what I've learnt reading this forum and getting involved, is potentially where the supposed OU is being created. Normally you think, a submerged object that floats will rise with the force of the volume of water that it was displacing, and to sink it back down to that same level, the same force must be applied to the object... work in = work out.

However, it seems that that it may be the fill and drain approach of the water applied within the ZED means that the requirement of energy to submerge the object in the first place by surrounding it with water, isn't as high as trying to force the object down into an already filled container. So once the cycle completes, the object sinks/falls with the draining dropping water level, and there's a bit left over. Maybe?


Amo