An Object-Oriented Approach to the Post-Processing of Cylinder Bore Distortion, Valve Seat Distortion, Valve Guide-to-Seat Misalignment and Cam Bore Misalignment 2017-01-1075

In CAE analysis of cylinder bore distortion, valve seat distortion, valve guide-to-seat misalignment and cam bore misalignment, nodal displacements on the cylinder bore inner surface and on the gage lines of valve seats, valve guides and cam bores are typically output. Best fit cylinders, best fit circles and best fit lines are computed by utilizing the output displacements of the deformed configuration. Based on the information of the best fit geometry, distortions and misalignments are assessed. Some commercial and in-house software is available to compute the best fit cylinders, best fit circles and best fit lines. However, they suffer from the drawback that only one best-fit geometry can be computed at a time. Using this kind of software to assess distortions and misalignments of engine components would be tedious and prone to error, since data transfer as well as the intermediate computation has to be done by hand, and the process is not automatic. This manuscript presents an object-oriented approach to the solution of the above problems. Common operations of finding the best fit geometry are designed as classes. By instantiating these classes, the best fit geometry can be computed automatically and the final distortions and misalignments of all cylinders, valve seats, valve guide-seat pairs and cam bores can be assessed automatically in a unified software framework. The presented technique can substantially save the post-processing time and avoid common errors.