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An Object-Oriented Approach to the Post-Processing of Cylinder Bore Distortion, Valve Seat Distortion, Valve Guide-to-Seat Misalignment and Cam Bore Misalignment
Technical Paper
2017-01-1075
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
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.
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Citation
Chen, W., Adimi, R., Chen, X., Brewer, T. et al., "An Object-Oriented Approach to the Post-Processing of Cylinder Bore Distortion, Valve Seat Distortion, Valve Guide-to-Seat Misalignment and Cam Bore Misalignment," SAE Technical Paper 2017-01-1075, 2017, https://doi.org/10.4271/2017-01-1075.Also In
References
- Coope I.D. Circle Fitting by Linear and Nonlinear Least Squares Journal of Optimization Theory and Applications 76 381 388 1993
- Cox , M.G. and Jones , H.M. An Algorithm for Least Squares Circle Fitting to Data with Specified Uncertainty Ellipses IMA Journal of Numerical Analysis 9 285 298 1989
- Gander , W. , Golub , G.H. , and Strebel , R. Least Squares Fitting of Circles and Ellipses Bulletin of the Belgian Mathematical Society 3 63 84 1996
- Umbach , D. and Jones , K.N. A Few Methods for Fitting Circles to Data IEEE Transactions on Instrumentation and Measurement 52 6 1881 1885 2003 10.1109/TIM.2003.820472
- Kasa , I. A Circle Fitting Procedure and Its Error Analysis IEEE Transactions on Instrumentation and Measurement 25 8 14 1976
- Shakarji , C.M. Least-Squares Fitting Algorithms of the NIST Algorithm Testing System Journal of Research of the National Institute of Standards and Technology 103 6 633 641 1998
- Goulb , G.H. and Loan , C.F. Matrix Computations The Johns Hopkins University Press Baltimore, MD 1983
- Stewart , G.W. Matrix Computations Academic Press, Inc. Orlando, FL 1973
- Nash , J.C. Compact Numerical Methods for Computers: Linear Algebra and Function Minimization Adam Hilger, Ltd. Bristol, England 1979