Numerical Simulation And Experimential Study On Intake Port Of SAICD19 Diesel Engin

The quality of intake port structure has a significant impact on the engine intake performance,which affects engine power,fuel-economy and emission level.Therefore it's a question how to design an intake port with high efficiency and low cost that all OEMs have to solve.With the development of computer technology,using computational fluid dynamics technology(CFD)in engine port simulation has become a reality.At present,the main design method of the intake port is running the numerical simulation on 3D intake port model first,and then optimizing the simulation results by intake port flow test.In this thesis,the intake port of SAICD19 diesel engine is designed through the combination of numerical simulation and experiment.The 3D modeling software is used to set up the SAICD19 inlet port model for numerical simulation.The CFD software is used to meshing and simulating the intake model.The distribution of airflow in the intake port and the distribution of pressure,velocity and turbulent kinetic energy are calculated.The motion patterns of the airflow field in the intake port and the influence of the port structure on the airflow field are studied.A steady flow port test rig is established,the test flow is and the evaluation method of intake port test performance is determined.The performance of airway is verified and the influence of valve lift height on airflow coefficient and eddy current intensity is studied.In this thesis,the numerical simulation of the flow coefficient,eddy current intensity and measured results are compared,indicating that under the high valve lift,the simulation results consistent with the measured results.In this thesis,SAICD19 engine intake port performance is benchmarked with other engines,indicating that SAICD19 engine intake port performance belongs to the international upstream level.