Recently, tumble in intake port and dynamic-pressure-wave effect of intake flow are used to promote the performance of SI engine. But not yet is acceptable consensus obtained about the relation between above factors and the performance of SI engine. I...
Recently, tumble in intake port and dynamic-pressure-wave effect of intake flow are used to promote the performance of SI engine. But not yet is acceptable consensus obtained about the relation between above factors and the performance of SI engine. In this paper, combustion analysis was done upon three cylinder heads which possessed different tumble values to observe the effect of tumble upon the performance, and it was concluded that there are an optimal tumble value for a given condition in the combustion system. Pressure waves of intake runner were also surveyed to consider their effects upon the performance and these pressure shapes could explain the trend of volumetric efficiency curve.<br/>