Effect Of Exhaust Particulate Content On Turbocharger Turbine Operating Characteristics

Along with the,domestic and foreign energy problems as well as the importance of environmental issues, the use of the vehicle engine technology to reduce fuel consumption, reduce emissions of pollution has become one of the main forms of energy saving and emission reduction,and the exhaust gas turbocharger exhaust gas is generated by the engine running directly as power,can use the exhaust gas cnergy better.The previous studies only consider the exhaust gas, but in actual work, the engine at low speed under the condition of insufficient fuel burning, waste gas are carbon particles, so this paper takes into account the amount of carbon particles in exhaust gas.Due to the internal flow field of turbocharger test method requires a large cost and difficulty of extraction of the experimental results is large, so the flow of software simulation of the turbocharger turbine end to further optimize the design of the structure is of great significance.Study at home and abroad this paper experiment data and relevant turbocharger flow simulation based on different engine speed, different combustion condition, the content of solid particles in the exhaust gas will be different, so the flow of different speed turbine end analysis.The steady flow field at the turbine end of turbocharger is emphatically studied.Using the impeller and volute structure design software CFturbo 3D modeling of the turbine end, flow control model,the basic theory of equations, the hybrid model and through flow field calculation in the turbine end, the theoretical research methods of its internal flow field, and establishes the geometric model of flow field calculation.Given the boundary conditions of the field simulation analysis, the flow field distribution characteristics of the turbine end of the turbocharger are analyzed from three cases of low speed to high speed by using fluid simulation software Fluent,The simulation results show that the flow field of fluid flow in uniform, diesel engine under low speed condition, in the end to import between turbine volute tongue section, fluid velocity and temperature are greatly decreased in the shell near the wall, the shell wall face of gas adsorption was more serious, and this type of shell material materials and surface processing and manufacturing the smoothness of a great relationship;In the flow field of turbine wheel, because in low speed condition, the engine combustion is not sufficient, the content of solid particles is relatively large, resulting in gas flow instability, gas motion in the rotating flow field is relatively complex, the speed change is relatively large, the flow field is still a small range of swirl,exhaust fluid energy loss small. When the speed increases, the combustion is relatively sufficient,and the solid content of the exhaust gas is very small. At this time, the exhaust gas flow is the same as that of the pure gas. The change characteristics of the flow field of the turbine are basically the same as those of the pure gas.In order to further reduce the energy loss of the fluid and reduce the range of change, there is still room for optimization and improvement of the turbine's shape. This paper provides an important reference for the optimal design of the turbine end of the turbine power output.