ORIGINAL: chevy43
I'm confused about what the cetane booster is doing as well. I don't think it changes the auto-ignition temp and it almost seems like it would make detonation worse. But I have to say it seems like it helps.
I flew again today for about an hour on my Black Brew 4 parts to 1 part Davis Plane. I works well once the engine is warmed up.
I'm also wondering when we mix fuels with different auto ignition temps whether we get an average or we get different parts of the fuel lighting off at different times. If it is the latter it will allow us to time the layers of the combustion event to best suit our needs.
20% oil really seems like more than necessary with pump diesel. I bet I could go lower but I really don't know how to tell when to stop so - maybe I will leave it alone.
Treven.
Treven,
An excellent suggestion. Kero has an AI of 420 and ether has 170. Quite a spread. So it's easy to see that the one brings the other up or down and we see the result in our engines. Gasoline and naphtha have an AI of some 250 and so, being better than kero, addition of same would average out to a better AI than kero alone. This is what Kelly was getting at, I think.
So we may just be back to square one in all of this. Our engines WILL run on just kerosene and oil. That oil can be a highly refined, modern grade of castor and it WILL stay in suspension as long as the ambient temperatures are reasonable. Or that issue can be eliminated altogether with the use of 50 weight Aviation oil. But for those of us that demand it, throttling suffers with little or no ether. Greater amounts of CB makes it worse.
A mechanical solution is being considered but some snags have been encountered. Theoretically the device should work but a chemical approach that works automatically and every time and never breaks may be a better way to go. But you never know.
The biodiesel and SVO and even crankcase oil was interesting and informative. Who would have thought ANY of this was doable. And ONLY doable if you use an electric starter.
Greg,
Your input has been very valuable and we all appreciate your prodding to apply more science and less speculation to all of this. I still keep forgetting that all I have to do is do a Google on any question and it's there, somewhere. Flash point, autoignition, cetane numbers. All relevant and contributing factors.
BUT, it's not over till the fat man leaves the stadium.
My gut feeling is that there's modern chemistry available that was not considered before because, well, it's not SUPPOSED to work.
Maybe a winter's worth of a break from the problem will allow all we've learned, unlearned and forgotten to boil and bubble in our synapses and something strange and wonderful will emerge.
The .15 is rebuilt and ready for more abuse. Kelly has offered a new approach that has merit and will be tried. If only the #$%^% weather will hold. Global warming? HAH !!
Most interesting project you have on the go. And you're also into electric in a big way. Variety is the spice, for sure.