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KOH and SS resistance

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warj1990:
Thanks for the tips.

Putting down one more graph of today's experiment.

This includes the graph from the other day also.

My next setup will be over-sized flat SS plates. (verify different surface area VS voltage needed).

My cell setup was not designed for high current, a #4 x 40 screw for outer electrode and #6 x 32 for inner electrode.

As you can imagine I am smoking the connections to these.  I need a # 8 wire, good for 50 amps, and I am going with Brass connection bolts.

I did attempt 1 run without KOH it was 4 amps at 88 volts.  Gas production did not seem impressive and the water heated up rather fast.
Gas production was improved with the KOH, results of higher amps.

88 volts * 4 amps = 352 watts
(maybe tomorrow I will run a voltage vs amps on just water - for power in right now it doesn't look good).

warj1990:
Wanted to post a thought on this setup.

water is a voltage dependent resistor.  The higher the voltage, driving the system, the lower the resistance.  So the power input is about a squared function.

As an example
At 2.4 volts it draws 10.6 amps, Power is 25.44 watts. Resistance is (2.4/10.6) 0.2264 ohms.
At   4  volts it draws 37    amps, Power is 148 watts.    Resistance is (4 / 37)     0.1081 ohms.

I know what you are thinking, been looking over this all day also. There are 2 things to look at here.
1 the water resistance went down - so the cell can pass more current and be more efficient.
2, connecting 4 tubes together in parallel will achieve the same thing, 2.4 volts @ 42.4 amps.  This is still more efficient at 101.76 watts.

Now what IF...
You can achieve a high voltage pulse and deliver several amps low voltage?  This would be kind of like a flash circuit where the hv pulse allows the electrons to flow.  This is also similar to the plasma discharge spark plugs.

The big difference is how fast the water consumes the high voltage pulse.

The high voltage pulse could be 12 volts @ 1 amp, 12 watts, while the high current is 2 volt @ 20 amps, 40 watts.

Expected water resistance at 12 volts 0.055 ohms (need to verify this with more testing and data)
At this expected resistance the cell is able to handle (2 volts / 0.055 ohms) 36 amps.

So with 2 secondary windings on the transformer and a diode tied in from the high voltage to the low positive voltage we may be able to achieve greater than 100% efficiency.  (based on current known methods).
The grounds on both windings would be tied together on one end and sent to the ground of the cell.  The positive would be taken to the positive of the cell.

Current is going to take the path of least resistance, which is mostly the water with KOH added.

warj1990:
No experiment time the last few days.

I need to find a fast way to verify the voltage drop - is it due to the movement of water, because of the H2 and O2 causing the circulation of water, or because of the voltage alone.

I have only seen one brief article on water movement and resistance.  While it vague on a message board and the question was asked why did the water resistance drop when it was in motion.

So now the question is can I get lower resistance by just allowing the water to flow and not need the high voltage pulses.

warj1990:

Large surface area allows lower voltage and more current draw.

Kind of already knew this one, but again documenting some tests.

One disappointment is on the single cell 3 volts @ 20 amps, 4 volts @ 40 amps.
An exact double - the offset results I had when I first started this did not appear.

LATE EDIT - an exact double in voltage would allow exact double in amperage - this only increased by 1 volt and doubled the amperage.
If the effect was not here voltage would have been 6 volts for 40 amps, not 4 volts.

The results are in the 2 and 3 cell tests.

I am pushing the limits of the variac - it is rated at 130 volts @ 20 amps - but keep in mind I am pulling up to 64 amps out of it.
(the overall power is under 250 watts, but really not intended for so many amps drawn at low voltage)

warj1990:
Here is tap water with a single cell.

Gas production rate seemed correct to current flow.

Around 80 volts the graph moves slightly higher as the water is heating up.

My data collection was for every volt, however I did not find a significant resistance change as I have in my other experiments.