Aces High Bulletin Board
Help and Support Forums => Aces High Bug Reports => Topic started by: pembquist on March 13, 2012, 11:01:48 AM
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Don't fly jug but did last night, M, bug is when e6b is open using wep decreases fuel burn GPH and increases flight duration. Did it on both sorties. Have film if wanted.
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I don't think that that's the only plane that you see this happen with. I've been told it hast to do with water injection.
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its normal and not a bug, complex engine stuff :headscratch:
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okay. any idea how it works? I've been scratching my head. If water injection, is it water to gas greater pressure rise than air/fuel alone? Phase change of water extract more heat from combustion so more mechanical energy less waste heat? Or just that you can run engine leaner without burning valves so less fuel same air, advanced spark?
liked subject "jug bug" sad to see go.
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I don't know, there has been a complete discussion a while about it in aircraft & vehicules IIRC
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will try search, (often unlucky with it), thankyou for the info.
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Water injection (water glycol mix) cools the cylinders allowing the engine to operate at a higher manifold pressure (producing more power) without overheating the cylinders.
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Thanks for reply thought I would add this part which goes to fuel burn reduction, from wikireadya: As a general rule, the fuel mixture is set at full rich on an aircraft engine when running it at a high power settings (such as during takeoff). The extra fuel does not burn; its only purpose is to evaporate to absorb heat. This uses up more fuel, and it also decreases the efficiency of the combustion process. By using water injection, the cooling effect of the water allows the fuel mixture to be run leaner at its best-power setting. Many military aircraft engines of the 1940s utilized a pressure carburetor, a type of fuel metering system similar to a throttle body injection system. In a water-injected engine, the pressure carburetor features a mechanical derichment valve which makes the system nearly automatic. When the pilot turns on the water injection pump, water pressure moves the derichment valve to restrict fuel flow to lean the mixture while at the same time mixing the water/methanol fluid in to the system. When the system runs out of fluid the derichment valve shuts and cuts off the water injection system, while enriching the fuel mixture to provide a cooling quench to prevent sudden detonation.
Due to the cooling effect of the water, aircraft engines can run at much higher manifold pressures without detonating, creating more power. This is the primary advantage of a water injection system when used on an aircraft engine.