Effect of Helical Winding Angle on External Pressure based Buckling of Partially Filled Thin Composite Cylindrical Shells

Effect of helical winding angle on buckling load of partially filled thin composite tubes is investigated in this work. Experiments are conducted on both empty and partially filled S2 glass tubes to estimate structural contribution of the filler material to improve buckling strength of shells. Chosen filler material mechanically simulates behaviour of typical solid propellant used in rockets for aerospace applications. FE analysis results with inclusion of non-linear effects correlates well with the experimental data. Three series of experiments are conducted to quantify the effect of helical winding angle and increase in volumetric loading fraction (VLF). Results confirm appreciable improvement in strength of filled tubes for higher VLF. For the chosen pattern of winding, lower winding angle provides more strength to the tubes against external pressure buckling.