An Experimental and CFD Study on the Effect of Diesel Helical Intake Port Design on the Swirl Ratio

摘要

Two different intake ports of a passenger car diesel engine were tested on the steady flow bench and swirl ratio data were obtained.To study the influential factors,a 3-D model was estahlished and CFD simulations were carried out to study the flow field in the intake ports and cylinder for the engine on the motoring conditions.The simulation results were in good agreement with the experimental data,thus validating the fidelity of the model.Then the flow fields were analyzed and it was found that the design details of the helical intake port had great influence,on the swirl ratio.A further discussion of the influence of parameter η of the helical intake port on the swirl ratio was made and the simulation results showed that the combination of a helical intake port and a tangent intake port was a key factor in getting a higher swirl ratio.