Three Dimensional Simulation For Dual-Intake Ports Of Turbocharged Diesel Engine

The air flow inside the cylinder plays an increasingly importance role in the high efficiency and low pollution diesel engine. And the intake ports are the most influent for the air flow inside diesel engine, so the study of the flow characteristics of intake ports is very important and significant. In this paper, three dimensional transient numerical simulation of the intake process in a turbocharged diesel engine is to study the transient flow properties of dual-intake ports.In this paper, the AVL FIRE is employed in simulating the steady flow status in combination ports of the helical and the tangential, with the same conditions as the steady flow experiment. The simulation results are compared with the test results, which show that consistency as the theoretical foundation for further research on the transient numerical simulation.The transient numerical simulation of the intake process in the turbocharged diesel engine is conducted, with the analysis of changes with crank angle inlet under the influence of gas flow. Through the three dimensional cloud distribution of the diesel engine under different crank angles, the microscopic study of the transient intake process is carried out. And the swirl or tumble ratio, the average turbulent kinetic energy, turbulence dissipation rate, average speed, and mass flow as the average amount of transient cylinder quantitative are selected to research the flow changes of intake process.Then from the forms of the combination, the intake flow is studied of the dual-helical ports and dual- tangential ports, and the effect of the intake performance of the three combination forms are analyzed, which prove that the swirl and intake capacity are very different.Finally, from the structure of the intake ports, spiral room height, valve convex platform height, airway gradient and airway angle are used to study the influence of the performance of intake ports, and the results indicate that results the swirl is easier influenced than intake capacity on the structural parameters.