Those who read this may be of engineering background, and many may be of other backgrounds and experiences, so I will attempt to present this for all who would take the time and interest to read this, to benefit to the degree that you choose.
In the auto application, the hydrogen and oxygen are not being separated. Some call this Browns Gas. When the hydrogen and oxygen from the electrolysis is combined, the volatility goes up and my experience is that a flame will not be produced. There is a very short burn time when this is ignited, a quick "POP" is produced. It's quite possible that this process causes a shorter "burn time" of the gasoline mixture in the cylinder of the reciprocating engine when introduced through the air breather on the car.
The first attempt to understand this art, was to make a quart jar generator out of an old mayonaise jar, as shown left. In the photo there are switches,and Ampmeter. I drilled two holes in the firewall to allow a power cord from the battery, which had an in-line 20 amp fuse installed, and the output gas tube from the jar to the air intake. I drilled a hole in the plastic air breather filter compartment and installed a "barb" to connect the gas tube. This tube was a 1/4 inch rubber tube similiar to the vacumn lines in the engine compartment.
When all this was hooked up we did the first road test. The car was filled with gas, and then proceeded from Hobe Sound, here in Florida, out Bridge Road, and to Lake Okeechobee. We went south to Canal Point, turned around and returned to Hobe Sound, where the car was refilled to calculate the milage. The pump indicated 2 gallons to go 81 miles. That looks like 40 mpg. About 3/4 of the way home, the jar was getting very hot. The switch was thrown off, so the generator wasn't running for the full trip. The trip was an ideal condition to get the best milage possible, as the driving speed was 45-55 mph. There were no stoplights or heavy traffic, all of which deteriorate the mpg.
Now we mount this thing in the car under the hood, as shown. The wires are hooked up to the controls in the car next to the driver seat as shown previously to the second switch and ground. Now there are two generators, as the glass jar is still connected inside next to the driver. The two generator hydrogen gas output tubes are connected in the engine compartment through a TEE so both can be working at the same time. I can switch electrical power to each generator, off and on, with separate switches. The ampmeter will indicate the total current drawn from the battery and alternator.
At this point, I'm thinking "the more hydrogen generated, the better the gas mileage". So as shown at the left, I got two new electrodes and mounted then so they were 1/4 inch apart and used a nylon bolt and nut as a spacer. Then I put a full tablespoon of natron (electrolyte) in the jar and put the cap on. All the electrolyte dissolved in the water so I know that the solution was below saturation. Before installing in the car, a quick check on the bench with the battery charger and small 12 volt battery, yielded what looked like 16 amps and 17 cubic inches a minute of gas. The water in the jar was really active.
Now the new jar gets installed in the car replacing the mayonaise jar, and all the connections are made. Now I have to run up the road halfway to Stuart on an errand, and the jar gets turned on for approximately a 20 minute trip. At this point the jar is quite hot.
While at the destination, I park, shut everything down, and maybe 5 minutes later start the car, and while leaving the driveway, I switch the jar on, in which a small explosion occurs, or a loud "POP" may be a better description. I look down, and the cap has blown off the jar and the top part of the glass jar is broken where the hooks on the electrodes hit during their exit.
What seems at the instant to be a disaster, is really a blessing. This was a great learning opportunity.
Now let's upgrade the 18 inch PVC tube with 2 additional electrodes and a new control circuit as shown on the left. The 4 inch PVC tube will now have 4 electrodes, 3 of which can be individually made (+) or (-). One is permanently wired to (-). Now I can control the current from inside with combinations of polarities of the electrodes.
Another mileage report is in. This one shows about 24 mpg. This driving was 200 miles of going to Winn Dixie which is approximately 4 miles down the road. One trip to Palm Beach Airport, which was 80 miles round trip. The number crunched out to be 24 mpg. Even though the pollution is drastically reduced, I still think better mileage can be achieved. We should get a reference mileage, without using any hydrogen. The old Pontiac has about 180,000 miles and is a 1990 Bonneville.
For the next step, the canister was removed from the car and 7 more tablespoons of electrolyte were added to the solution. After re-installation in the car, the current now jumped to drawing over 20 amps with just one electrode turned on from the control panel in the car. In checking each electrode, one at a time the center one blew a 20 amp fuse. All the fuses were replaced with 35 amp slow blow. Now, one electrode turned on, and 3 being used as ground, draws more current than previously witnessed with 2 on and 2 ground. The fuse from the power line from the battery also has a 35 amp slow blow fuse, so that, presently, is the total current limitation. Doing some research on alternators, I found that, for this car, they are rated for 105 amps.
As the amount of HHO gas was increased, the mileage has not exhibited better mileage, which does not conform the logic of expectations. It may be time to consider the affects of the new combustion process with respect to the oxygen sensor. This device is located in the exhaust manifold/exhaust pipe. After doing some research on it's operation, consider the following:
Now, Let's work on the fuel mix control. Disconnect the oxygen sensor, and replace the signal input to the computer with a separate control from inside the car. See the photo at the left, notice a potentiometer mounted in the upper left of the control panel. A voltage divider, capacitor, and a zener diode were wired in a circuit with a 5K pot, to manually adjust what the computer would normally see from the oxygen sensor.
The output of the oxygen sensor, as described in www.howstuffworks.com, works like this: When the fuel mixture is too lean, the output voltage of the sensor will go to a low value, such as 0.1 volt. Conversely, when the mixture is rich, the output voltage will go higher, maybe 1.1 volts. So if the voltage is set higher from the substituted control, the computer will be fooled into reducing the fuel fed through the injectors as it thinks the mixture is too rich. After connecting the circuit, and starting the car, the effects of the control can be noticed listening to the motor. The mixture can be leaned up until the engine runs rough.
I have to wonder now, if this alone could be used to increase gas mileage.
The original 18" X 4" PVC tube was reduced in length to 12". The electrode design was changed to what is shown at the left. It becomes apparent that effeciency of HHO generation is inversely proportional to heat generated in the process. This is apparent in the recirocating engine used to propel the the car. In an effort to reduce the energy required to create the HHO the R (resistance in ohms) has to be reduced to as close to zero as possible. The I2R factor creates the heat.
Notice the photos at the left, there are 4 bars very close together approximatly 1/8 to 1/4 inch spacing. The resistance reduction due to the electrode spacing in this configuration appears to be in a range of .25 ohms. Now it will be impractical to connect this directly to the 12 volt car battery and generator. The load on the alternator will be 50 amps which will be out of a range for practical operation. Now, another power source will have to be considered to power this low impedeance.
One approach is to use a power transister, to be used as a current regulator, however, this will require a heat sink, and the heat ineffeciency factor returns. Other considerations are solar, small wind turbine generator, magnetic vibration generators, and static generators. Some of these have the advantage of being speed sensitive. The faster the car goes, the more energy delivered to the HHO generator, thereby increasing the amount of hydrogen generated proportional to speed.
Other considerations have become apparent, such as the required change of ignition timing due to a shorter combustion time of the hydrogen, oxygen, and gasoline mixture as compared to a longer combustion time for gasoline only. It is now obvious from the test runs, that the timing of the ignition could be retarded as the percentage of hydrogen is increased in the combustion chamber.
It now becomes obvious that the computer which considers all these things will require special programming.
Volume/min = Displacement X RPM /2
The reason for dividing by 2 is that there is two revolutions for one breath. One revolution for each cylinder is used as a compression stroke or Power stroke.
The formula we need is this:
Now let's get a feel for how much hydrogen we are generating. The setup at the left is what we will use. Procedure:
Here is an interesting graph of some characteristics of this generation process. This test was run with a glass jar on the bench as shown above. By adding electrolyte to increase the DC current in increments, the resultant gas (HHO) generation characteristics are exposed. It seems that around 9-10 Amps a generation barrier is broken and the efficiency radically increases.
The Red Bar displays the DC amps read on the battery charger.
The blue bar is the measurement in cubic inches per minute of (HHO) gas generation.
This graph shows the phenomenon in a different format. This one displays the energy necessary to create 10 cubic inches of HHO gas as measured in Amp-minutes of energy vs. the static DC current in amps.