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Fig. 10 from the paper by Michael P. Nemeth, Vicki O. Britt, Richard D. Yound, Timothy J. Collins, and James H. Starnes Jr., "Nonlinear behavior of space shuttle superlightweight liquid-oxygen tank under prelaunch loads, Journal of Spacecraft and Rockets, Vol. 36, No. 6, November-December 1999
ABSTRACT: The new Space Shuttle superlightweight external fuel tank flew for the first time on 2 June 1998 (Space Transportation System-mission 91). We present results of elastic linear-bifurcation buckling and nonlinear analyses of one of its major components; that is, the liquid-oxygen tank. The contents include an overview of the structure and a brief description of the finite element code that was used to conduct the analyses. Results are presented that illustrate three distinctly different types of nonlinear response phenomena for thin-walled shells that are subjected to combined mechanical and thermal loads that launch-vehicle shell designers may encounter. A procedure is demonstrated that can be used by structural analysts and designers to obtain reasonable, conservative estimates of linear-bifurcation, buckling-load knockdown factors for shells that are subjected to complex loading conditions or to characterize the effects of initial geometric imperfections on nonlinear shell response phenomena. Results are also presented that show that the superlightweight liquid-oxygen tank can carry loads in excess of twice the values of the operational prelaunch loads considered and that a fluid-filled launch-vehicle shell can be highly sensitive to initial geometric imperfections.
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