tron@fluke.UUCP (Peter Barbee) (04/25/85)
In article <337@ttidcb.UUCP> loco@ttidcb.UUCP (CM Dev. Group ) writes: >Since carbs require >vacuum to meter fuel, I don't see how it could be any other way. Correct me if I'm wrong, don't carbs use velocity to meter fuel? Isn't this what the venturi principle is all about?
mat@hou4b.UUCP (Mark Terribile) (04/27/85)
>Correct me if I'm wrong, don't carbs use velocity to meter fuel? Isn't this >what the venturi principle is all about? Carbs meter fuel the same way that airplanes fly: Bernoulli's principle. There's some pretty physics involved in demonstrating it, but what it amounts to is this: Given a volume of fluid travelling past a surface, the energy of that fluid is a function of the velocity of the fluid and the pressure the fluid is under, multiplied by the volume of the fluid. In order for the energy balance to work out (I am miles away from my textbooks and my intuition is too rusty to work it out ...) the pressure that the fluid experiences perpendicular to the direction of travel must be less than the pressure it would be seen to experience if it were at rest. As the velocity increases, the pressure must decrease. ---> ---> ---> ---> ---> ---> ---> ---> F L O W ---> ---> ---> ---> ---> ---> ---> ---> ------------------------------ ----------------------- | . . . | | . . .| |. . . | |. . .. .| |. . .. | reduced pressure -- from Mole End Mark Terribile (scrape .. dig ) hou4b!mat on 5/1/85 ..,,. mtx5b!mat ,.. .,, ,,, ..,***_*.