melting pistons and lean fuel mixture 3

[mustben]

i am designing a gasoline vaporizer that will run a stream of air thru liquid gasoline then inject the the mixture into the intake manifold of a 6 cylinder 98 nissan maxima. this will be in addition the gasoline injected via the EFIs. i hope to be able to run a lean mixture perhaps up to a air fuel ratio of 20:1. i have been told to be careful about melting the pistons because the lean operating mixture can reach very high temperatures. i am a retired chemical engineer without any automotive experience. all feedback will be gtreatly appreciated. mustben

 

[turbocohen]

Modern fuel injectors with multi hole orifice plates atomize fuel well. If the fuel particle leaving the injector is smaller than 10 microns it is as good as vaporized by the time it is transported to the chamber and turbulence along with heat vaporizes it the rest of the way.
Next gen DI will make port injection obsolete.

 

[Daniel1123]

An idea off the wall here is that gasoline is a oil and depending on your geographical location there are many diffrent blends of gasoline diffrent times of the year hot locations have a more oily fuel and cold locations have a "dryer" fuel. With hot weather fuel being more oily then cold weather fuel we can assume that not 100% is able to evaporate as fast as it is injected and burned on a day to day changing temperature unless this is a perfect world with perfect blended gasoline. By the addition of water into the combustion process at correct ammounts. If it was "fogged" into the intake stream before fuel is added allowes the fuel to float on the water droplets giving a larger surface area for evaporation and for the fuel to burn off the surface of the water particles. The extra heat from a lean burn would be used to make steam giving a higher peak pressure after TDC and controling detionation. I know with diesel applications this has been used alot wiht great sucess in pro stock tractor pulling, tho these engines have turbochargers and the water is also used to control EGT so as not to damage turbos and EX valves.

 

[patprimmer]

Danie

Your post is really quite inaccurate, especially with regard to the manner in which water injection works.

If you search this site yo will find half a dozen long threads that explain it properly.

Regards
Pat
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