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'94 115 Johnson starts in driveway but not in the ocean?
Interesting ideas Terry.
Maybe it would be better to simply start with the diesel engine, since it can already tolerate the full lean-burn scenario. Then install a second injector in the cylinder, timed to inject water, later than the fuel nozzle. Hopefully, the incoming water wouldn't quench the flame. The problem may be to get the combustion done, early enough to give time for water injection to follow and water evaporation to occur. bob Terry K wrote: By melting the main bearings? Fouling the rings? Burning the valves? Coking up the combustion chamber? Dissolving the plasic intake manifold, causing lean, hot combustion, burning holes in the piston domes? By melting the fuel pump rubbers? Good old Ford engines, eh? The flappy things are the reed valves, which admit fuel air mix to the crankcase, where it is compressed by the down stroke, then popped into the combustion chamber through the intake port, and after chasing out the exhaust, is compressed on the up stroke. If they get leaky, compression can fall, and power can diminish, with gas fumes puffing out of the carburator. Some exhaust is retained, mixed with the charge, as is done in four strokes with the egr valve, to reduce lean burn effects, like high tempratures and NOx smog formation, by cooling and reducing efficiency of the explosion. Is it possible that if only spark plugs and valves and pistons and rings and bearings like in a diesel could withstand a true lean burn engine, with no monoxide discarded, that a little water injected after perfect combustion would expand in a small combusted fuel charge, and convert the internal combustion engine into an internally fired steam engine, exhausting only hot carbonated water and uncombusted nitrogen? Much heat energy is thrown out the tailpipe of "modern" i.c. engines. The exhaust should be at about 213 degrees farenheit, not 1200.The exhaust should be just hot enough to keep injected water as high pressure steam, pulling all the power out of the phase change cycle. A resonant exhaust would reduce it's gas volume by causing the exhaust steam to condense into water just after exiting the combustion chamber, helping to scavenge the cylinder. The temperature variations on each cycle is what kills this design, and the requirement for precise water injection timing and quantity. You would need a tiny hemispherical combustion chamber in the centre of the piston dome for the fuel, and large displacement to maximise the steaming part of the cycle. As the water boils, it increases the pressure while cooling the mix, because water boiled expands to 1700 times it's volume as a gas, while absorbing heat. However, the combustion, at high compression, would still generate NOx unless it's combustion could be kept cool enough to prevent it, by heat sinking the initial combustion by the proximity of internal metal masses of the engine, which would contribute to the boiling of the water injected. Golf ball dimples on head and piston dome? So goes the age old story of the secret "water burning" engine suppressed so many years ago by those opposed to efficiency in gasoline engines, also known as petroleum wholesalers. Too hard for Ford? Who owns Ford? Terry K |
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