CFD Study On Vehicle Diesel Intake Port

The structure of intake port directly affects the quantity of fresh air and the strength of swirl in cylinder. Which have relations with the Engine's power, economy, and exhaust emissions.So the design of intake port is very important in the process of Engine design. Based on experiential design and steady flow test.The traditional port design method needs a long developing period, high costs.Moveover is hard to get the ideal scheme. Using the method of 3D numerical simulation to research on intake port. Which could acquire not only the integration parameters.But also microcosmic information of the flow field in abundance. Which can provides important basis to improve and design the intake port optimizingly.The study consulted a lot of intake port research paper that written by domestion and international scholars in the aspects of port study. And comprehensive domestic and international intake port and cylinder internal air flow simulation calculation and experimental study situation. Based on a type of domestic diesel engine tangent intake port. Selects the mathematici and numerical models of flow in port. Build a three-dimensional tangent intake port model, valve seat model,valve model and cylinder model of the selected diesel engine through Pro/E software. And combined into intake system model.Then manage the established model using GAMBIT preprocessor, and calculate the compartmentalization of the grid and export the logical mesh profile using CFD.Introduced the TUST-102 steady flow test bench that developed by the National Combustion Laboratory,Tianjin University. Use of common evaluation parameters of airway flow characteristics, dimensionless flow coefficient and dimensionless swirl ratio basis for evaluating the performance of inlet. Made a experiment study on the steady flow test bench, and using the result of steady flow test rig as boundary conditions.Import the mesh profile into the FLUENT software in CFD,set the related technical parameters. In order to understand the speed of the cylinder, pressure microscopic information,Determined byκ-εmodel,SIMPLE algorithm,Simulates the tangent intake port three-dimensionally in CFD software FLUENT. Validates the calculational results via the Ricardo evaluation acquired through test rig. And draws a conclusion that the two have a basicly accordant trend. Which shows the feasibility of applying CFD to simulation in diesel intake port. Provides detailed pressure, flow, turbulent kinetic energy and path line information of the port. On the basis of which give a proposal of intake port improvement. And improved intake port model according to the proposal. Then simulates the improved intake port again in CFD software. The result show that the modified model performance increased. Which father shows the validity of appiying CFD to improving diesel intake port. The study achieved the flow performance of tangential intake port, through the methods of stability fluxion of port experiment and CFD numerical simulation.Get a large number of images, visual microscopic information of the gas flow. Provides a theoretical basis for product design and improvement. Though the method and design process used in this paper was special to the design of a tangential inlet of a diesel engine,but they are also could be used in other intake port design process.Both in academic and engineering has some practical valve.