Low-velocity Impact Response of Delaminated Composite Conical Shells in Hygrothermal Environment due to Time-delay

This paper presents a finite element based method to investigate the hygrothermal effects on the transient dynamic response of delaminated composite conical shells with initial twist impacted at arbitrary locations by multiple spherical impactors at a predefined time-delay. An eight-noded shell element has been used in the present analysis based on the Mindlin's theory. The multi-point constraint algorithm is incorporated to ensure the compatibility of deformation and equilibrium of resultant forces and moments at the delamination crack front. The indentation laws of Hertz are implemented to compute the contact force and displacement arising from each impact on specific locations of the cantilevered conical shell. Results are presented to depict the influence of important parameters like, temperature, moisture concentration, twist angle, size of delamination and time-delay on the impact response of delaminated composite conical shells.