STRESS AND STABILITY ANALYSIS OF SHELLS WITH ELLIPTIC CROSS-SECTION

Elliptical shells will find a wide application in future aerospace con cepts. Because of aerodynamic reasons and aspects of configuration fus elage structures of hypersonic aircraft will have elliptical or quasi- elliptical cross-sections. In considereation of volumetric efficiency it seems to be necessary having tank concepts with elliptical cross-se ctions, too. As mentioned by the authors in earlier published papers ( [1], [18]) elliptical shells in contrast with those of circular cross- section show several stability problems when loaded with internal pres sure. Computer programs for structural investigations of shells with n on-axisymmetric cross-sections based on the Transfer Matrix Method hav e been developed. The goal was to have an easy to use and fast running program system which uses well suited substitute mod els for calculat ing deflections, loadings and stability effects. This also offers the possibility of wide range parametric studies in a tolerable amount of time. In the following the theory used, modellization and calculation methods will be shortly introduced. The results achieved will be prese nted and discussed. On this occasion also comments on structural effic iency of elliptical shells under pressure and some methods to solve st ability problems will be given.