Automobile Electrical and Electronic Systems, 5th Edition

Fuel control

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• The volatility and latent enthalpy of the fuel.

• The droplet size.

• Controlled turbulence.

The effect of droplet size is important, as the rate of droplet burning depends

primarily on the rate at which oxygen becomes available. It is, however, vital for

the droplet to penetrate some distance from the nozzle around which burning

will later become concentrated. To do this, the size of the droplets must be

large enough to obtain sufcient momentum at injection. On the other hand,

the smaller the droplet the greater the relative surface area exposed and the

shorter the delay period. A compromise between these two effects ...