| 摘要 |
PROBLEM TO BE SOLVED: To simultaneously promote the improvement of performance at the time of homogenous combustion and the improvement of performance at the time of stratified combustion in a direct injection spark ignition type internal combustion engine. SOLUTION: The minimum cross sectional area A (cm<2> ) per cylinder of a suction port 3 is set to a scope of V/A=45 to 55 V is a stroke volume (cm<3> ) per cylinder}. By this way, the promotion of vaporization of fuel due to an increase of a suction air flow speed, the improvement of suction air filling efficiency due to cooling of suction air, and the promotion of mixture and homogenization of fuel doe to the strengthening of air flow (longitudinal flow) in a cylinder can be achieved at the time of homogenous combustion. Moreover, a suction air flow speed is increased at the time of stratified combustion so that swirl can be reinforced furthermore, fuel can be transported to the vicinity of an ignition plug more satisfactorily, and the combustion characteristics at the time of stratified combustion can be improved furthermore. That is, when it is set like V/A=45 to 55, both of the performance at the time of homogenous combustion and the performance at the time of stratified combustion become compatible at a high level.
|
