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View Full Version : why didnt the US use....



fordfan25
04-16-2005, 08:02 PM
.....NOS or other boosters like the germans and japan?

SkyChimp
04-16-2005, 09:25 PM
Cuz they didn't need it.

However, the US Navy apparently experimented with liquid oxygen injection.

jarink
04-16-2005, 09:45 PM
Didn't the P-47 and F4U use water injection?

fordfan25
04-16-2005, 09:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by jarink:
Didn't the P-47 and F4U use water injection? <HR></BLOCKQUOTE>

well i dont think thats the same thing. if im not wrong wich i may be the water injection was just to keep the enfien cooler during maxed out power. NOS and meth is more of a booster that puchs the engien harder than it would normaly be able to on its own with normal fuel.

fordfan25
04-16-2005, 09:53 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by SkyChimp:
Cuz they didn't need it.

However, the US Navy apparently experimented with liquid oxygen injection. <HR></BLOCKQUOTE>


need? who cares about need.Were talking about the fact that it woulda made it much more easy for me 60 years later online lol. i would "THINK" that haveing that as an option for a pilot might make a big deffernce on weather or not he made it back alive.

Tully__
04-16-2005, 10:18 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by fordfan25:
...If im not wrong wich i may be the water injection was just to keep the enfien cooler during maxed out power.... <HR></BLOCKQUOTE>

Partly. Because water and meth injection keep the fuel/air mix cooler, you can pump more in before you get destructive detonation (run higher boost), giving more power. Meth also acts as an Octane modifier, allowing even more boost (more fuel/air) to be added and even more power to be developed before melting pistons/valves/cylinder heads.

Nitrous gives more or less the same type of benefits as meth, though the maximum duration of use and actual power boost differ a bit. In some situations NO2 is better, in others methanol is preferable.

One13
04-17-2005, 05:35 AM
Wasn't the use of water/methanol or NO2 injection determined by the rated altitude of the engine?
The rated altitude is the altitude at which the supercharger can be run at its maximum rate (delivers its full pressure) to give maximum power, i.e. Jumo 213E gave 1,310HP at 35,000ft.
Water/methanol injection improved performance below the rated altitude, it acts as an anti-detonant. Cooling the charge it allows higher compression ratios.
Nitro oxide injection improves performance above the rated altitude. It provides extra oxygen for combustion, acts as an anti-detonant and cools the charge (air entering the engine).
It enables the engine to continue to deliver high power at grater altitudes than would otherwise been the case. Rolls-Royce experimented with NO2 for a high altitude version of the Mosquito.

raisen
04-17-2005, 05:08 PM
Tully_ hits the nail on the head, water/methanol or water injection is designed to lower the charge temperature in the engine, like an intercooler. By lowering the charge temperature it allows the engine to suck in a greater mass of mixture in the same volume of air, giving more bang during the whole suck, push, bang, blow thing.... Whilst uncommon it still gets used to this day in rally cars. In rallying, it enhances charge cooling, with modern intercoolers allowing very high boost pressures. Turbocharged BMW grand prix engines used it with an intercooler and exotic fuel to get 1400 hp from a 1.5 liter engine.


Primarily nitrous oxide when introduced into the mixture decomposes to give more oxygen when that mixture is burnt, allowing more fuel to be burnt. Secondarily it is injected as a liquid gas, which expands, and cools the charge (the incoming mixture). In fact, failure to richen the mixture when using nitrous is the same as dramatically weakening the mixture, and can be seriously destructive. Inject a lot of nitrous, and a lot of fuel and that alone can be disastrously destructive, ask a drag race engineer (think in terms of bent rods, cranks, burnt pistons). More oxygen + more fuel = more power....

Raisen