Thermal and Mechanical Buckling Analysis of Hypersonic Aircraft Hat-Stiffened Panels with Varying Face Sheet Geometry and Fiber Orientation

Ko, William L. (1996) Thermal and Mechanical Buckling Analysis of Hypersonic Aircraft Hat-Stiffened Panels with Varying Face Sheet Geometry and Fiber Orientation. Technical Report NASA TM-4770, Research Engineering, NASA Dryden Flight Research Center.

Full text available as: PDF - Requires Adobe Acrobat Reader or other PDF viewer.

Abstract

Mechanical and thermal buckling behavior of monolithic and metal-matrix composite hat-stiffened panels were investigated. The panels have three types of face-sheet geometry: flat face sheet, microdented face sheet, and microbulged face sheet. The metal-matrix composite panels have three types of face-sheet layups, each of which is combined with various types of hat composite layups. Finite-element method was used in the eigenvalue extractions for both mechanical and thermal buckling. The thermal buckling analysis required both eigenvalue and material property iterations. Graphical methods of the dual iterations are shown. The mechanical and thermal buckling strengths of the hat-stiffened panels with different face-sheet geometry are compared. It was found that by just microdenting or microbulging of the face sheet, the axial, shear, and thermal buckling strengths of both types of hat-stiffened panels could be enhanced considerably. This effect is more conspicuous for the monolithic panels. For the metal-matrix composite panels, the effect of fiber orientations on the panel buckling strengths was investigated in great detail, and various composite layup combinations offering high panel buckling strengths are presented. The axial buckling strength of the metal-matrix panel was sensitive to the change of hat fiber orientation. However, the lateral, shear, and thermal buckling strengths were insensitive to the change of hat fiber orientation.

EPrint Type:	NASA Technical Memorandum
Keywords:	Hat-stiffened panels, Mechanical buckling, Metal-matrix composites, Thermal buckling, Varying face sheet geometry, Varying fiber orientation
Subjects:	(31 - 39) Engineering: (39) Structural Mechanics
ID Code:	189
Deposited On:	16 July 2004
Additional Information:	36 pages.