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Hnm. Then how to easily approach those conditions? Without serious engine modifications?
Add diesel to gasoline to increase energy content? (And over here it costs less 4/5 ratio to gasoline) and then tame it with water?
Please correct me if i am wrong, these are my assumptions:
Warm air is less dense as the molecules have more energy they move faster, bump in to eachoter so take up more space. As ther is less o2, engine injects less fuel. So you reduce your effective engine size relative to howmuch fuel you can burn.
Warm air molecules, especially o2 move faster. So the chance that they bump in to fuel and combust is more likely. This increases burn speed. Burn speed is important for lean burn, because during lean burn when there is less fuel it burns much slower and you end up ejecting still slowly burning fuel from the piston which can burn the valves.
Warm air can also cause combustion of the fuel before the spark, this is not good at all beacuse the piston tries to move against the other pistons and something breaks.
Water gas has a much better expansion rate when they receive energy, this way they can generate more usable mechanical power from the combustion heat.
Water droplets when they evaporate with the combustion heat will cool the piston. This means lower combustion temperatures, so less energy is lost to the coolant.
During the compression stroke the water condenses in to droplets and the later evaporates. Some say that while they transform in to steam, they help the fuel vaporize and increase combustion efficiency.
The presence of water in the cylinder prevents detonation (or retards it). It also slows down the burn speed. The first thing is an advantage as mentioned previously, you can use lower quality or more energetic fuels, or increase compression to gain efficiency. The second part may not be so good as fuel may not have enough time to burn before exiting the piston. This has to be controlled or monitored so in my opinion a cylinder pressure monitoring system is interesting.
Steam injection. Not sure what to think of this. It will take more volume than water droplet injection that is for sure. It carries a lot of energy. When steam encounter cooler fuel, it will transfer its heat to fuel helping it vaporize. What will it do to detonation? No idea...
Please correct my assumptions if i am wrong. (These are for gasoline engines, not diesel, as they can run very very lean).
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