Opinions and Suggestions on my head build-up

[bjones18]

Yeah, definitely a good thread.

Would the atomization characteristics hold true for both an intake that's under vacuum and one that's under boost?
Let's say our river is now a large pipe that is under pressure. Will the 1000 psi nozzle still have the same atomization effect?

1. Water (and fuel) vaporize under complete vacuum. (you can boil water at room temp!)
2. Pressure (or vacuum) is not constant thru the runner length, cross-section or valve position.
3. Nozzles work on pressure differential. if the pipe is at 950psi and the nozzle pressurized to 1000, there is only a 50 psi differential. I don't know what psi our injectors are spraying at. Many things start to come into play, including spray pattern.

We are talking about a micro-second of spray. Bosch, Denso or the like have spent $$$ working on this.

 

[bjones18]

Sorry to bring up a really old thread, however I have been reading Engine Management by Greg Banish. Since injector pulses are designed to squirt fuel on the back of the valve (and hit intake walls) BEFORE the valve is opened, a non-polished intake port will help atomization, but not through turbulence, but rather surface area. A micro-roughed surface should have alot more surface area compared with a polished surface.

So... since fuel is injected into the port before the valve opens, maximum surface area for the fuel to wet will help evaporation, and atomization. This of course depends on the surface tension of fuel on aluminum.

In effect, fuel might grab micro-roughness and spread into a thin film as opposed to wanting to "glob" together in droplets.

A puddle of water in your driveway will evaporate faster if it is spread-out over a large area. And since injectors squirt before valve opening, there may be puddles.

The book is worth buying.