The Research Of Gas Flow And Mixing On Diesel Engine With EGR

Air motion inside the cylinder of diesel plays an important role in the process of fuel sp ray and combustion, determines the economy, power output, and depresses exhaust emissions and combustion noise of the engine. So the flow in diesel engine is one of the key problems in design all the time. As an important technology of controlling oxidation of nitrogen emission from the engine, the technology of exhaust gas recirculation (EGR) is widely used in modern diesel engines. So it is necessary to analyze the stratification of the mixed gas and temperature in cylinder to check the effect of EGR clearly.In the research of diesel flow problem, some parameters can also be measured by instrument; however, it is due to the complicated construction of diesel engine that the related details cannot be obtained. In comparison with test that studying flow problem by using multi-dimensional numerical simulation cannot only greatly decrease research cost, save labor and material resource, shorten development period, but also get some data which is unmeasured by experiment and flow information in detail. The outline of the port is measured with three-dimensional coordinate measuring instrument or laser measuring instrument. Then, with modeling software the data file of the outline of the port is built after dealing with the data from measuring.Multi-dimensional transient numerical simulation of flow in single cylinder working Process of a 135 diesel is performed. Geometry model including spiral inlet channel, offset combustion chamber, tangential exhaust channel, cylinder and intake and exhaust valve is established...