Two principal aspects of fuel distribution in multicylinder engines have been investigated; namely, time variation (cycle-to-cycle) of air-fuel ratio in a given cylinder and geometric variation (cylinder-to-cylinder) of air-fuel ratio in different cylinders.
To study the time variation problem, a new technique capable of measuring the air-fuel ratio for individual engine explosions has been developed. An analytical study has provided a correlation between power loss and fuel economy loss with the statistical variance of geometric distribution.
To determine the possible cause of geometric maldistribution, a series of experiments using a gaseous fuel to simulate complete vaporization was conducted. The effects of various means of mixing the fuel and air on geometric distribution are discussed.