E-8/B-707 Wing Station 320 Transition Fit Fastener Finite Element Analysis

摘要

The stress around a Hi-Lok installed in structure typical of the upper wing station 320 of a Boeing E-8/B-707 aircraft using the finite element method. The requirement came from the Corrosion Kinetics Group (University of Virginia, UVa) of the Aeronautical Systems Center (ASC), Aeronautical Enterprise Program Office (ASC/AA), Aging Aircraft Division (ASC/AAA) Air Vehicle Health Management program. The specific stress result addressed in this work was in response to the installation of the Hi-Lok fastener into the subject structure to include initial pre-load and a mild 4 mil (0.004 in) diametric interference (transition) fit. MSC/PATRAN was used to define the solid model, element mesh, loads and boundary conditions for analysis by MSC/NASTRAN. MSC/PATRAN was used again for post processing of the model solution to create stress fringe contour plots and to assess the validity of the finite element model. The stress contour plots are presented for within approximately two diameters of the fastener at multiple planes through the skin thickness for hydrostatic as well as the x, y and z components of the stress tensor. While the solution presented here was not the highest precision possible for such an analysis, it was judged to be a good first order analysis which met the immediate need of the corrosion kinetics group. Several areas of improvement were suggested for follow on work in this area as requirements dictate a higher fidelity solution.