Fluid Field Analysis Of Diesel Engine Intake System Based On Computational Fluid Dynamics(CFD)

Diesel engine is a kind of equipment which provides power for mechanical devices.Its intake system plays an important role in controlling intake volume and improving diesel engine effectively.In recent years,the frequent faults of the intercooler and air filter in the intake system have not made the diesel engine to work properly.Therefore,it is necessary to analyse the flow field in the intake system of the diesel engine.Firstly,the 3D models of air filter,intercooler,turbocharger and helical intake port of diesel engine intake system are established by using software CREO3.0.The finite element analysis models of each component and the whole intake system are established by using software named ANSYS FLUENT.And the correctness of each component model is verified by comparing with the results of relevant literatures.Secondly,the flow field of the intake system is analyzed in normal and fault working conditions,and the variation rules of velocity,pressure and turbulent kinetic energy and flow trace are obtained.Finally,the fluid-solid coupling analysis of air filter in fault working condition is analyzed using software named ANSYS FLUENT and ANSYS WORKBENCH.the deformation of air filter are obtained,which is verified by the deformation of air filter on site.The analysis results show that:(1)the component model of intake system established in this paper is consistent with the analysis results of relevant literature,which proves that the component models established in this paper are correct and reliable;(2)under normal conditions,the maximum pressure of intake system occurs in turbocharger,the value is 155KPa;The maximum velocity occurs in turbocharger,the value is 550m/s;(3)the maximum pressure occurs in the inlet of the intercooler at the fault working condition,the value is 162 KPa;The maximum velocity occurs in the turbocharger,the value is 515 m/s;(4)under the normal working condition,the maximum strain of the air filter is 0.17mm and the maximum stress is 105.03 MPa,which does not exceed yield limit of material;the air filter produces the elastic deformation;(5)in the fault working condition,the maximum strain of the air filter is 0.775 mm,and the maximum stress is 465.97MPa,which exceeds the yield limit of material.Its yield limit of material is plastic deformation.The research results of this paper lay a foundation for the further study of the flow field in the intake system,provide a certain reference value for the optimization design of the intake system,and also create a theoretical basis for the study of the blocked causes of air filters.