Testing of a Composite Conical-Cylindrical Shell

Michelle Leann Tillotson; Marc R. Schultz; Nathaniel W. Gardner; Cyrus J. R. Kosztowny; Chiara Bisagni

NASA NTRS · 20220017838

Testing of a Composite Conical-Cylindrical Shell

Michelle Leann Tillotson·Marc R. Schultz·Nathaniel W. Gardner·Cyrus J. R. Kosztowny·Chiara Bisagni

Abstract

Launch-vehicle shell structures, which can be comprised of both cylindrical and conical sections, are known to be susceptible to buckling due to their large radius-to-thickness ratios. The advancements in composite manufacturing and numerical methods have enabled designers to consider more nontraditional shapes, such as connecting the conical and cylindrical sections with a toroidal transition to create a single-piece conical-cylindrical shell. This single-piece construction eliminates the need for a heavy interface ring between sections and has the potential to save mass. To better understand the buckling behavior, a composite conical-cylindrical shell was designed, fabricated, and tested. Prior to test, a finite element model that included thickness variations and radial imperfections was created. The test article buckled elastically at 251.8 kN, approximately 8.8% higher than the predicted buckling load of 231.4 kN Continued research in conical-cylindrical structures has the potential to expand the design space for launch-vehicle structures and lead to improved designs and reduced weight.

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Michelle Leann Tillotson, Marc R. Schultz, Nathaniel W. Gardner, Cyrus J. R. Kosztowny, Chiara Bisagni. Testing of a Composite Conical-Cylindrical Shell. https://ntrs.nasa.gov/citations/20220017838

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