4弁小型高速DIディーゼルエンジンの可変スワール吸気ポートに関する研究 : 定常流試験と数値解析による超高スワールヘリカルポートの検討〔熱工学, 内燃機関, 動力など〕

抄録

To reduce exhaust emissions in high-speed DI diesel engines, it was reported that a high swirl ratio is required for partial load operating conditions. In this paper we discuss the high swirl helical intake port necessary to put this combustion concept into reality. The impulse swirl method, instead of the paddle wheel (vane) method, was determined to be appropriate for estimating the high swirl ratio. To select an effective shape for the port, a parts-assembly port model was designed, and a parametric study of the helical port shape was carried out. An auto mesh generator for helical port numerical analysis was developed, and a 3-dimensional simulation of the intake flow pattern necessary to make a high swirl ratio was conducted.