Parameterized Design Based On CAD And Modal Analysis Of Engine Crankshaft

As an important part of engine, crankshaft has not only held up the whole dimensionand weight of engine in dimension parameters, but also influenced the reliability and usefullife of engine to a great extent. It operates under the common action of gas stress of periodicalchange, inertia stress caused by reciprocation and whirling, and flexural moment and torqueof aforementioned stress, and it shows a complex motion of bending and torsion, which maycause serious fatigue stress even to fatigue invalidation. Hence, researching parameterizationdesign and modal analysis of crankshaft has specified application value.On the basis of CAD present status of the domestic and foreign research, this thesis hasdeveloped and set up feature-based sub-features library and parts library of vehicle enginecrankshaft, integrating programming of VC++ 6.0, database management of Access andfurther development of SolidWorks API based on SolidWorks, so as to completeparameterized design of crankshaft rapidly and accurately. Furthermore, it has carried outfinite element modal analysis of certain crankshaft with ANSYS software compared withexperimental analysis and validated the calculation results of finite element. The specificcontents are as follows:(1) Based on SolidWorks, the thesis has implemented parameterized design withprinciple of dimension drive through extracting structure parameters of crankshaft. And it hasalso combined the sub-features into a crankshaft entity with the multi-solid technology ofSolidWorks, through choosing sub-features structure and carried out 3D modeling ofcrankshaft finally.(2) The thesis has set up the database of parameters data of crankshaft, user database and model database with software of Access, and input the whole parameter data and demandsof standardized model into parameter database of crankshaft for management. It can alsoreal-time query, modify and add operation for database through ODBC technology.(3) The thesis has carried out further development with VC++ and SolidWorks APIfunction, and built plug-in units of SolidWorks. And it has also created the man-machineinteraction parameterized interface with friendly interface and complete function, andimplemented seamless connection between plug-in units and SolidWorks.(4) The thesis has studied experimental modal analysis for the crankshaft and obtainedthe dynamitic characteristics. And then it has carried out finite element modal analysis for thecrankshaft with finite element software of ANSYS, and calculated by Lanczos method toobtain eigenvalues and the corresponding vibration modes coinciding with experiment results,which will offer important grounds for further intensity analysis and dynamic optimizeddesign of crankshaft.