How bad do we need a pressurized fuel tank?

[DaveC426913]

Isn't a pressurized tank of fuel a Very Bad Thing? Pressuring the fuel using a pump means that, unless the pump is active, you don't have to worry about pressure. But if the tank is pressurized passively, you're sitting on a bomb.

 

[dE_logics]

We've already discussed that.

 

[dr dodge]

a vented, unpressurized tank is probably more dangerous. vaporization can take place easy from vibration/aggitation. positive pressure could keep the fuel below its vapor pressure
thats why the tanks are slightly pressurized now. it cuts "random emissions" from the car just sitting in the heat

dr

 

[dr dodge]

on the drive home yesterday, the critical design flaw surfaced (impending pun)
the surface area of the interface between fuel and pressure would need to be constant, to get constant output pressure. that would mean the tank would need to be exactly the same shape and size from open to full. The fuel would also have to stay pretty much level all the time. Most fuel tanks are non-uniform in shape, often smaller at the top, and lengthening out at the bottom. this could greatly effect the whole car design as the gas tanks are "designed to fit in the leftover space"

dr

 

[dE_logics]

The design needs to be a of constant geometrical, that's the only way it will work.

The volume can be trimmed off to give it a constant geometry...this will be a major drawback.The flue level in bikes matters significantly...you can actually feel the difference.