> Thus,
>the filling process causes a small quantity of fuel to be sprayed
>and vaporized near the filler area. In addition to being untidy
>this could be a safety issue, i.e. there has been a report of a
>fire in a Europa possibly due to a static spark at the filler
>opening -- this fuel spray could cause a flammable mixture in
>exactly that area.
It would not surprise me if this was the cause of the fire in the German
Europa. Maybe a spark between the filler funnel and the vent line vapour? A
sort of Van de Graaf generator at work? Having talked to the guys I can't
think of any other cause.
>To minimize fuel spray from the vent during filling I am
>considering adding an expansion volume in the vent line, the
>concept being that air being vented pushes droplets of fuel along
>through the vent line due to the air velocity. By adding a
>section of larger diameter to the vent line the velocity in that
>section will drop, reducing its ability to carry droplets which
>should then collect and run back toward the tank. Flammable
>fumes will continue to the vent outlet but droplets and spray
>should be reduced or eliminated.
This would reduce the velocity of vapour and droplets and might reduce the
voltage generated. It would help a lot to increase the rate of filling,
which is painfully slow due largely to the slow venting of the tank. Ever
felt the air rushing out the vent?
Good thinking, John. Any more ideas?
Graham
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