Mechanical Behavior Analysis Of The Crank-connecting Rod Mechanism In Internal Combustion Engine

The crank—connecting rod mechanism is one of the most important components of internalcombustion engine, it endures complex and alternate load and it is the key point and difficulty ofthe engine design. The traditional design and analysis methods are so simply that they can not besatisfied with the actual demands. The Multi-body System Dynamics and the Finite ElementAnalysis make precise analysis of crank—connecting rod mechanism being true.First of all, briefly introduces the principle and basic analysis theory of crank—connecting rodmechanism in this paper, on this basis, software MATLAB is used to process the kinematics anddynamics analysis to calculate the various components at any time, anywhere on themovement(displacement, velocity and acceleration, etc.)and components of the inter-force.Through the simulation analysis, made recommendations on production practices of thecrank—connecting rod mechanism, and also laid the foundation for optimization design of it. Basedon the Multi-body System Dynamics and the Finite Element Analysis, considering complicatedcontact relationships, oil membrane stiffness of main bearings, bearing gap and some othernon-linear factors, the shock response characteristics of the crank—connecting rod mechanism andconnecting rod mechanism was analyzed. The simplified model of the crank—connecting rodmechanism was established based on the PRO/E. Its shock-resistance performance was predictedand evaluated by ANSYS under rated condition and static condition. Finally, Based on the theoryof modal analysis on vibration problems, and conduct the modal analysis of the simplified modelof the engine crankshaft by ANSYS. So we can get the frequency of the free modal and the constraint modal, and make a comparison on them. Furthermore, by viewing the modal shape ofthe constraint modal, we can put forward some reasonable suggestions for the structuralimprovement of the crankshaft.According to the results of the research, using the computer simulation technology, andcombined with three-dimensional modeling software, the dynamic response analysis of theengine crank—connecting rod mechanism can be done. Furthermore, the results are satisfied. It hasgreat meanings, such as amending the crank—connecting rod mechanism, improving the design level,optimizing the character of engine. Generally speaking, it is an economical, effective andscientific method.