Structural Design Research On The Exhaust System Of Engine Based On Thermosetting Problem

This article discussed the development history of automobile engine onexploitation and design and the current situation of engine exhaust system onstructural analysis from the domestic and overseas. The solution and accomplishmentabout engine issues during development process were studied. Meanwhile, It came upwith the purpose and meaning according to the actual subject. It also put forward theresearch aim and concrete content on the basis of corporate planning.Firstly, the paper introduced the main theories, which were modal analysis theory,harmonic response theory, the engine heat loading theory, the fluid-structureinteraction theory and the structural optimization design theory.Secondly, the paper focused on structural features of the exhaust system. Themain components and their connection relationship were described. According tostructural features and the actual requirements of corporate, it came up with theproposal about the structural design research on the exhaust system of engine basedon thermosetting problem.Thirdly, based on the solid structure problem, it focused on dynamiccharacteristics of the exhaust system. The structural mode was calculated anddynamic stress of the exhaust system near the resonance zone was calculated by theharmonic response analysis, especially the dynamic stress on the structural crackingposition was focused on. The load excitation of the harmonic response analysis wasachieved by the experiment of the corporate. Finally the good evaluation about thestructural vibration characteristics was got.Fourthly, the paper studied the heat problem of exhaust system, calculating theheat load, thermal stress and thermal deformation. It mainly simulated the workingcondition of the exhaust system under the stability conditions of engine. The insideand outside field of exhaust manifold was calculated, and the thermal boundaryconditions of manifold outer wall was got. According to the theory of fluid-solidinteraction, the thermal boundary conditions of manifold outer and inner wall wereused as load to calculate the temperature field of exhaust manifold, meanwhile theaccuracy of the exhaust manifold assembly temperature field calculation results wasverified by thermal test. It simulated the working condition of engine test and studiedon the simulation of thermal stress and thermal deformation.At last the solution was came up to solve the problem of the structural cracking, and the optimal structure designing based on the lightweight was used. Then theoptimized structure was calculated and the result was feasible.The article found out the cause of the structural cracking problem of the engineexhaust system, it also put forward the reasonable solution to the problem. Above allit proposed the technological process of structural design and analysis. It providedsupport and help for the further development of the product.