抄録
The effects of the spray impinging part and swirl ratio on the in-cylinder airflow were numerically analyzed in the combustion chamber of the impinging diffusion direct injection diesel engine using KIVA-3 code. KTVA-3 code was enhanced to cater the impinging part as an internal obstacle by adopting the virtual droplet method, which is relatively easy to implement. Numerical result shows that the turbulence generation is promoted by the impinging part and is transformed by the squish flow into the piston cavity. The secondary flow is generated beneath the impinging part as well. The secondary flow area increases as the distance between top surface of the impinging part and bottom surface of the cylinder cover increases. It also increases as the swirl ratio increasing.
