Originally Posted by
Crash one
My apologies.
Seems to make sense as the extra fuel would cool the area further making the situation worse?
Not really. The fuel itself is warmer than the ice so the liquid fuel would tend to warm things up. But the jets are at the same place in the constriction of the venturi, so other than keeping the jet itself clear the fuel doesn't touch anything that's iced.
Once the fuel is released into the intake air it atimises into afine spray, and then it is supposed to vapourise. If it DOES vapourise it will cool the surrounding air (google "latent heat of vapourisation"), but there is always significant doubt as to whether it does at anything more than low power settings simpoly because it doesn't have time in the brief dash betwixt jet and cylinder.
Vapourisation promotes good fuel consumption and in some cases "cleaner" combustion and emissions, and it can also have an untercooling effect which improves charge density. But in most carburetted setups full vapourisation actually limits the maximum power available because the vapourised petrol occupies far more space in the inlet manifold and cylinder than fine droplets would do.
The power of any piston engine is ultimately limited by the amount of air you can make it breathe, and if you can make the fuel stay in nice concentrated droplets you can actually get more mixture into the cylinders than you could if the volume was cluttered-up with vapourise petrol. Once in the cylinder the droplets (again) have an intercooling effect which can allow you to run a slightly higher compression ratio if you are so inclined.
This has been known for decades, and it's the main reason why the
really high performance setups still favoured carburettors over indirect fuel-injection well into the late 80s. F1 cars only really committed to fuel injection when the formula started introducing reductions in permitted fuel capacity.
But I digress...
PDR