Water injection

[Fuelie Fan]

PS: if you knew ALL the theories, then you'd probably have a pretty good grasp of all the real-world advantages, wouldn't you? Considering that this subject has had umpteen million papers written about since (and even before) it became a popular subject on WWII aircraft, there's a lot of theories concerning the subject.



To paraphrase a smart man on another site: H20 injection provides a power benefit IF and ONLY IF the compression ratio is too high for available fuels, and it provides this power increase almost entirely by allowing the operator to return the spark advance closer to MBT as opposed to having to retard the timing. The water is an anti-detonation device, it slows the early phase of combustion. Other "power increases" due to charge cooling and so forth are negligible (it's cooling the air, but also displacing it with steam that doesn't burn).