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hhonewbie
08-21-2009, 04:18 AM
Has anyone ran a dry cell plate stack horizontal rather than vertical?
Has anyone tried plate gauges under 1mm?

Stevo
08-22-2009, 11:05 AM
I am working on one now. Horizontal Flooded Cell (HFC) where the plates are fairly simple in design. It is an 11 plate setup in this config:

-
n
n
n
n
+
n
n
n
n
-

If you have noticed, most all of the vertical designs have water flow issues. The idea (in theory) is that greater efficiency can quite possibly be had by forcing the water to flow across the plates in an uniform pattern. Essentially the water flows in the bottom of the electrolyzer and in a "S" pattern to the top of the electrolyzer. Of course, this sort of setup will need some sort of positive flow enabler such as a very small water pump. Something to keep the cells flooded and water flowing in the right direction. I have found one that does ~1-2 liters/min @ ~200-400 milliamps and retains chemical resistance. Considering all you want to do is keep the water flowing in a positive direction, the output from the water pump should be fine for most larger sized setups.

Overall, keep in mind that distance is yet another way to reduce current leakage and how well a cell displaces it's contents can be directly linked to how much consistent active surface area you are actually taking advantage of. Most VFCs play on the idea that the top output holes are not completely submerged in e-lyte, thus not consistently enabling current leakage. Keep in mind the key phrase: "not consistently enabling". This means that a very considerable percentage of the time these holes actually are enabling a certain amount of current leakage. This is not to mention the fact that the bottom holes (usually not staggered in most of the cells I see) are consistently enabling current leakage due to the fact that in a typical 4n/5n setup, there is approximately .5 - 1" of gap between the electrodes + and -. Remember that current jumps through the holes in the neutral plates.

Now take the HFC design into consideration. Instead of approximately .5-1" of gap between electrodes, you now have (in the case of my 4n design) approximately 12". I've attached a couple of pictures to show the little test I conducted to help provide proof of concept:

1-inch.jpg - shows the current leakage with electrodes 1" apart
distance.jpg - shows the distance at which I tested which was 12" apart
negative-12inch.jpg - shows the electrode during electrolysis at 12" from the positive
positive-12inch.jpg - shows the electrode during electrolysis at 12" from the negative

The e-lyte mixture was as follows:

-Distilled Water
-KOH
-Ratio: 3 tbsp/Gal

The power source:

-12 V 2/6A battery charger

hhonewbie
08-23-2009, 03:33 AM
If the only purpose of N plates is to manage heat why not do away with N plates and circulate/waterpump/radiator/fan electrolyte to desired temperature.

My thought was sandwiching folded fine mesh between negative plates to increase area at cathode?

Plate gaps 1-3mm

+
-
folded mesh
-
+
etc.

My consideration is to build smaller units using thin plates & fine mesh to gain area but at the same time keep current at a minimum without compromising HHO production.
More often I have seen small cells out preform large cells with low current, high production and wet cells perform just as well as dry cells. A small cell makes more sence because its cheaper to build and recondition.

Stevo
08-23-2009, 11:04 AM
You are correct in your way of thinking, but a few things stand out here:


Doesn't adding a fan or fans require yet more energy?
How will you keep your voltage down below ~2.5V/cell? Anything above that is generally considered a waste of energy and the reason for abundant loads of heat capable of melting a cell down.
Aluminum (what most radiators are made of) reacts violently with not only water, but NaOH and KOH. Check the Cole-Parmer chemical compatibility database online.
Even if #1 and #3 were cut out of the picture, how you would need to address #2 would be with a DC DC voltage converter/amplifier, which would cost you a bit of $


N plates have been addressed here several times in the past. Don't think of them as non-producers are that would be incorrect. However, I do agree with your idea of increasing surface area using mesh and in general when it comes to removing "current leakage" between the plates by using no neutrals. Yes, if you remove all neutral plates you don't get "current leakage", but that DC DC voltage converter/amplifier is going to be expensive. :)

hhonewbie
08-23-2009, 10:34 PM
Im still not sure about N plates even with all the posts about N plates. The enitial test will be without N plates and added if needed.
Another fan requires little energy. The radiator core would be copper not aluminium.
Im not concerned with PWMs and converters as they are costly. The cell would be self regulating with a relay vacum on switch to power cell and switch off when vacum is off.
My target is 5-25amps depending on KOH mix & production.
No DC/DC converter needed.

Its better to keep things simple. Complicating things by adding this or that leads to one thing after another$$$

Stevo
08-23-2009, 11:14 PM
Sure. Well good luck, have fun and be safe. Let us know what the results are. I'll be sure to open a thread with mine.