Carburation enhancement in an internal combustion engine by electrostatic atomisation of petrol

Abstract

A simple modification to a Weber carburettor enables the normal air-blast atomisation process to take place in the presence of an electric field when a voltage is applied to the petrol orifice. Laboratory tests on a modified carburettor are described. Normal premium grade petrol with an electrical resistivity of greater than 10⁹ Omega m, and also petrol doped with an antistatic additive which decreased petrol resistivity to 3*10⁵ Omega m was used. Aerosol size distribution was measured by a Coulter Counter. Using normal petrol the presence of an electric field appears to have an adverse effect upon combustion efficiency as the aerosol mean droplet size increased. With doped petrol the electric field has a pronounced effect, reducing the median droplet size from 50 to 26 mu m diameter.