Failure Analysis And Improvement Research On Automobile Engine Exhaust Manifold

In recent years,the rapid development of China's automobile industry,engine production continued to increase.As we all know,the engine is a vehicle power source,to play a crucial role in vehicle performance.The merits of an engine from the three main aspects to measure power,economy and emissions performance,which are closely connected with the exhaust manifold.Based on a displacement of 2.0L four-cylinder gasoline engine exhaust manifold design optimization,the original tightly coupled to the exhaust manifold with turbocharger,exhaust manifold and foreline into the catalytic converter,and from the selection,and structural design of the exhaust manifold material,CAE analysis and optimization direction will be described.First,start with the current situation and development trend of stainless steel from automotive exhaust systems,analysis of current situation and development trend of the exhaust manifold material to determine the choice of 2.0T exhaust manifold materials(cast iron or stainless steel).Secondly,the use of three-dimensional software CATIA structural design,and the use of CAE software on the exhaust manifold and catalytic converter before the temperature field and thermal stress analysis,structural prone to damage at the simulation results,and propose measures for improvement and optimization,thereby improving the reliability and efficiency of the structure design.The model has been thermal stress distribution manifold structure,stress concentration and stress is maximum proposed structure corresponding optimization and modification,effectively avoid structural damage caused due to stress concentration.Finally,according to the exhaust manifold cracking position,through the exhaust manifold structure comprehensive CAE analysis,including flow field analysis,thermal stress analysis,mainly due to the manifold cracks analysis,combined with the finite element analysis of discrimination tube structures were effective optimization improvements to reduce the stress at the crack structure,theoretically solve the crack problem manifold structure,providing a theoretical basis for further analysis of experimental verification.