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As part of an ongoing technical collaboration between Ford and Rouge Steel Company, a comprehensive study of door slam event was undertaken. The experimental phase of the project involved measurements of accelerations at eight locations on the outer panel and strains on six locations of the inner panel. Although slam tests were conducted with window up and window down, results of only one test is presented in this paper. The CAE phase of the project involved the development of suitable “math” model of the door assembly and analysis methodology to capture the dynamics of the event. The predictability of the CAE method is examined through detailed comparison of accelerations and strains. While excellent agreement between CAE and test results of accelerations on the outer panel is obtained, the analysis predicts higher strains on the inner panel than the test. In addition, the tendency of outer panel to elastically buckle is examined.

Finite element based stress analysis and fatigue predictions are practiced routinely in automotive body structural design and development. The accuracy of these simulation results is not fully understood or at least not well documented. Automotive body structures have many kinds of notches, metal thinning due to stamping and cold working etc. Modern fatigue assessment tools do take into account many of these complexities by Neuber corrections, mean-stress correction, critical plane selection, etc. Other challenges exist in the sensitivity to element quality, including warpage, size, element type, interpretation of results, etc. This case study is based on static loading and accelerated fatigue test conducted on a front-end body buck. The stress and fatigue correlations are designed to build confidence in the model and load inputs. The fatigue results are intended to reproduce durability issues that developed during a proving ground test and were then used to verify potential fixes.