The Finite Element Analysis Of Thermal Intensity And Mechanical Strength For Cylinder Head Of A Diesel Engine

Cylinder head is one of the most complicated and important components in internal combustion engine. Cylinder head, the top of piston and liner enclose to form combustion chamber. The explosive force and bolt pre-tightening force act on cylinder head, and its temperature is uneven due to the effect of working medium in combustion chamber and water jacket, so cylinder head suffers high mechanical and thermal stresses.It is the basis of structure design and modification to analyze temperature field and stress field of cylinder head correctly and further analysis of fatigue life。The design is timesaving and cost-effective by using the finite element method.In this thesis, FEA is employed on the cylinder head of engine. Lots methods are introduced to solve the problem. The model of cylinder head is made by Pro/Engineer while its elements are made by HyperMesh. The numerical simulation method is used for the cylinder head to the finite element analysis. The temperature field, thermal stress field and mechanical stress field are calculated separately. On the basis of this, thermal-mechanical stress field are calculated too. Finally, it's fatigue life with the outcome of the appeal is analyzed, and a way which can improve the structure of cylinder head is proposed.The strength analyse is of cylinder head is carried out under the thermal mechanical coupling loads. The result shows that the high stress zones exist around the valve guides holes that should make a special consideration in diesel design. Finally, the low cycle fatigue life of the cylinder head is predicted. Finally, a simple revised scheme is introduced on the calculation.