atomization enhancement

[Greg Hermann]

>At 10:10 AM 5/2/99 -0400, you wrote:
>>There has been some recent research that indicates the best atomization
>>occurs when the exhaust hits the puddled fuel behind the intake valve when
>>the valve opens.  Atomization of fuel as it leaves the injector is not
>>terribly important.
>
>Yes, but that's not atomization, that's vaporization... and if it's caused
>by the exhaust hitting the puddled fuel, that means it's being blown back
>into the intake runner causing intake dilution and fuel distribution problems.

BINGO, Dave!!

Not to mention that this approach to fuel vaporization is thermodynamically
far less efficient than ATOMIZATION! Using the latent heat of the fuel to
cool the inlet valve, only so the valve can rob heat from the next power
stroke to heat back up is a thermal inefficiency. Letting the latent heat
of well atomized fuel make the compression process in the cylinder more
nearly isothermal than adiabatic increases net power output by reducing the
amount of work which the engine must do during the compression stroke!

Good vaporization of fuel is important to emissions--but it can happen
either way.

Good atomization of fuel is important only to power and efficiency, so it
has been somewhat shortchanged in the research funding.

Regards, Greg