抄録
Experiments have been carried out to examine the influence of oxygen concentration in intake air and fuel concentration on flame speed for small gasoline engine by using carburetor and EFI system. The travel time of flame speed front is measured using ionization probes located at different point of cylinder head. The main conclusions are as follows: 1) the flame speed monotonically increases with increasing the engine rotation at any concentration in intake air. 2) Mean increasing rate of pressure is not affected by oxygen concentration in intake air and fuel concentration under without load. 3) It is possible to improve the combustion behavior with using EFI system for small gasoline engine.
