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Doing a bit of math using vaporization rate calculators:
Assumed injection amount - 0.02g per cylinder per cycle
Molecular weight of gasoline - 100.2g/mol
Mass transfer coefficient - 0.18 m hr
Area of liquid surface - let's assume the gasoline is squirted as a single droplet, and not as a spray. We have 0.000200 mol of gasoline, which, if in a sphere, would have a volume of 0.00448 liters. The surface area of a sphere containing 0.00448 liters is ~0.00096 square meters.
Vaporization pressure of gasoline - 9psi or 6.8kpa
Temperature - I put in 2500c.
I plugged these values into a few engineering calculators, and got numbers that were zero, rounded to the nearest tenth of a millisecond.
If a crankshaft is spinning at 2000rpm, that's 33 revolutions per second, or 12,000 degrees of rotation per second. Or, 1 millisecond per 12 degrees of rotation.
The vaporization worst case scenario is less than 0.1 millisecond. Assuming your injector just dribbles the fuel in, in a single large blob.
As to how this plays out in practice is another matter. This is my best attempt at academic honesty on the topic.
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