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Posted: Thu May 08, 2008 8:58 am
by SpudFarm
i am going to make a camera and a ignition coil setup, but if i talk to Larda he may digg up a flyback or something for me.
or i run like 10camera caps in one ignition coil
Posted: Thu May 08, 2008 4:45 pm
by psycix
MrCrowley wrote:And I can't remember, but does DDT have a higher chance of occurring at a lower mix then higher?
IIRC, in the rule you can divide the DDT runup distance on atmospheric pressure by the amount X mix.
If a certain fuel has a runup distance of 100" at atmospheric pressure, then a 2x mix would only need 50", a 3x mix 33, 4x mix 25" and so on.
Im not sure about what I stated above.
Its just a vague memory.
Posted: Thu May 08, 2008 4:59 pm
by DYI
Im not sure about what I stated above.
Its just a vague memory.
A vague memory indeed, from way back when people actually thought that 4x was approaching DDT.
In reality, the Nx has very little effect on the DDT runup distance of propane/air mixes. The increased pressure decreases burn rate, and the increased temperature of higher mixes just barely overcomes that effect. A 20x mix might burn a few m/s faster, but not enough to be really worrisome.