"self pumping" HHO cell concept...
 

Hi folks,

One of the things that bothers me about electrolysis cell efficiency in general is that you're dependant on the speed that the gas bubbles rise. It appears to me that the cell resistance rises as it waits for the bubbles to get the heck out of the way, making unnecessary heat... Agitation can be beneficial in helping bubbles to detach. Some commercial electro etching and plating setups have pumps to circulate the electrolyte, a nice idea, but makes things a little more complex.

So I spend a bit of time thinking about stuff like this, and a serendipitous solution presented itself the other day in the "everything for a dollar" store. I was looking for SS artifacts to press into service as plates, and noticed electric range/stove "reflectors" available for a buck a piece...These are shaped like a shallow bowl with a hole in the bottom.

So, imagine a stack of these "upside down" with the hole at the top, the bubbles will rise up the center where the hole is. Now here's the clever bit, because of the convex surface an aerodynamic effect will come into play similar to the Coanda effect, the electolyte will move up the center pumped by the bubbles, then will be drawn over the top plate making a lower pressure area over the curve, and inducing more flow in the center, which will be pulled through the plates. This should "self exite" quite strongly and create a toroidal (donut shaped) flow motion. Encouraging a little axial rotation would be good too, since then you would get a bubble vortex forming in the center, the heavier electrolyte thrown outward. This should also combat foaming problems that might happen in high output cells. The container ideally should have an inch or so clearance all round and maybe a baffle at the bottom, a rounded hump/shallow cone, and rounded corners to encourage the flow.

I am thinking that ziptie construction would work, with 3 zipties around each reflector, left loose enough so they can be pressed together with zipties around the whole assembly. The axial rotation could be set up by angling the spacing zipties a little. I'm thinking the "ends" of the ties should be brought out at the bottom, to allow smoothest flow at the top end.

Conceptually I see this as making a great amount of gas relative to plate area and current consumption and believe it may damp thermal runaway much more than in other designs. It may also be possible to run more plates, as near to the lower voltage limit as possible... you could tweak the voltage down until it was just forming bubbles slowly, and I suspect that as soon as those bubbles got moving, the whole thing would speed up and ramp gas production to remarkable levels.

Heat actually provides some of the energy in the process, so running hot isn't all bad, in fact the hotter they get the less power you need for given gas production. However, since you are typically not controlling power, you get into a thermal runaway problem. If this design limits heat production in the cell, then coupling it to waste engine heat will boost efficiency further.

BTW some method should be found of physically attaching it to the bottom of the container, or otherwise restraining it, otherwise it will tend to float/thrust it's way to the top of the electrolyte. Probably need to allow a reasonable depth of electrolyte over the top of this for it to work well.

This could be made a lot bigger, there's the smaller reflectors I was thinking of trying it with, then there's a larger size, and if you really want to go nuts, you could take a holesaw to the bottoms of SS mixing or salad bowls and make a huge beast.

I guess now I'm on the lookout for a good container to build it into...

Road Warrior

Why not wrap it with a finned heat sink. That may cool the outside fluid enough to help induce flow.

i posted a thred on another site of a design i made, i found it rely usefull to circulate the water
I fount id kept the water cooler as it was only passing the cell and not sitting in it, was also easy to refill using the second tank.

it was not to hard to set up i just had a small windscreen washer pump to do the job. i also used the second chamber as the first bubbler,

Roadwarrior

Nice idea but a bit hard to conceptualize without a drawing or better yet, a picture. Plz post when you can and let me know your results. Always interesting in new designs here. The problem with me is space under the hood, that is, that lack of it for my Jetta.

Yeah it will turn into a bit of a big sucker, 6" burner reflectors in a minimum 8 inch diameter container. I've just about got space for that in Marvin I think. There's prolly folks with various model cars that have found nifty new places to hide the battery for better weight balance at the drag strip or for getting huge cone filters under the hood, etc, so if this seems like a goer and you really wanna find space for one, it may be possible. Might try and knock up a sketch later... been useless at digitised drawing stuff since I lost my copy of PSP a year or two back.

Designs
 

I am currently typing up the best of my cell designs and will be giving out the information on all the parts i used and where i can links.

Russ . .

Just thought of a "canning jar/mason jar" version, cheap "soup ladles" with a half inch hole drilled in them would probably fit in a jar and have similar properties. As might small SS finger bowls...

I might end up prototypeing like that, because I'm having no luck so far with a decent container, could end up testing in an ice cream tub, but I don't fancy it's chances of holding up more than a week in use.

the thing you have to think about is it builds up pressure and heat

so far i have found the best to use is DIY store waste pipe it comes in all lengths and you can get lots of ends for it like the clean out cap makes life easy

Sorry I don't think I can find it in a relevant amount of time but there are pumped HHO cell designs out on the internet. The one I saw pumped fast enough that it had a water gass separater chamber before the water recirculated.

Another used exhaust gass blown or drawn through the cells to move the gas along. Your idea is fine; others have tanken different approaches to the same problem.

Ernie

Yeah i been struging to fined a design on the net, the way i did mine was i took the water from the top of the cell and pumped it back in to the bottom as it would flow past the cell cleaning it, i only used a slow pump but it did the trick.,

also if you want to clear the cell of bubbles you can use a ultrasonic foger